Only subtract home offsets for machine-centric XY

Use raw positions for G34 probing to honor M206 offsets
[cron] Bump distribution date (2022-05-29)
2022-07-17 15:18:57 -05:00 · 2022-05-29 18:49:20 -04:00 · 2022-05-29 00:21:51 +00:00 · 2022-05-28 17:40:08 -05:00 · 2022-05-28 17:34:36 -05:00 · 2022-05-28 17:09:08 -05:00
1633 changed files with 145110 additions and 42096 deletions
@@ -1,43 +0,0 @@
---
-name: Bug report
-about: Report a bug in Marlin
-title: "[BUG] (short description)"
-labels: ''
-assignees: ''
-
---
-
-<!--
-
-Have you read Marlin's Code of Conduct? By filing an Issue, you are expected to comply with it, including treating everyone with respect: https://github.com/MarlinFirmware/Marlin/blob/master/.github/code_of_conduct.md
-
-Do you want to ask a question? Are you looking for support? Please don't post here. Instead please use one of the support links at https://github.com/MarlinFirmware/Marlin/issues/new/choose
-
-Before filing an issue be sure to test the "bugfix" branches to see whether the issue has been resolved.
-
-->
-
-### Bug Description
-
-<!-- Description of the bug -->
-
-### My Configurations
-
-**Required:** Please include a ZIP file containing your `Configuration.h` and `Configuration_adv.h` files.
-
-### Steps to Reproduce
-
-<!-- Please describe the steps needed to reproduce the issue -->
-
-1. [First Step]
-2. [Second Step]
-3. [and so on...]
-
-**Expected behavior:** [What you expect to happen]
-
-**Actual behavior:** [What actually happens]
-
-#### Additional Information
-
-* Provide pictures or links to videos that clearly demonstrate the issue.
-* See [How Can I Contribute](#how-can-i-contribute) for additional guidelines.
@@ -0,0 +1,169 @@
+name: 🪲 Report a bug
+description: Create a bug report to help improve Marlin Firmware
+title: "[BUG] (bug summary)"
+body:
+  - type: markdown
+    attributes:
+      value: >
+        Do you want to ask a question? Are you looking for support? Please use one of the [support links](https://github.com/MarlinFirmware/Marlin/issues/new/choose).
+
+  - type: markdown
+    attributes:
+      value: |
+        **Thank you for reporting a bug in Marlin Firmware!**
+
+        ## Before Reporting a Bug
+
+        - Read and understand Marlin's [Code of Conduct](https://github.com/MarlinFirmware/Marlin/blob/bugfix-2.0.x/.github/code_of_conduct.md). You are expected to comply with it, including treating everyone with respect.
+
+        - Test with the [`bugfix-2.0.x` branch](https://github.com/MarlinFirmware/Marlin/archive/bugfix-2.0.x.zip) to see whether the issue still exists.
+
+        ## Instructions
+
+        Please follow the instructions below. Failure to do so may result in your issue being closed. See [Contributing to Marlin](https://github.com/MarlinFirmware/Marlin/blob/bugfix-2.0.x/.github/contributing.md) for additional guidelines.
+
+        1. Provide a good title starting with [BUG].
+        2. Fill out all sections of this bug report form.
+        3. Always attach configuration files so we can build and test your setup.
+
+  - type: dropdown
+    attributes:
+      label: Did you test the latest `bugfix-2.0.x` code?
+      description: >-
+        Always try the latest code to make sure the issue you are reporting is not already fixed. To download
+        the latest code just [click this link](https://github.com/MarlinFirmware/Marlin/archive/bugfix-2.0.x.zip).
+      options:
+        - Yes, and the problem still exists.
+        - No, but I will test it now!
+    validations:
+      required: true
+
+  - type: markdown
+    attributes:
+      value: |
+        # Bug Details
+
+  - type: textarea
+    attributes:
+      label: Bug Description
+      description: >-
+        Describe the bug in this section. Tell us what you were trying to do and what
+        happened that you did not expect. Provide a clear and concise description of the
+        problem and include as many details as possible.
+      placeholder: |
+        Marlin doesn't work.
+    validations:
+      required: true
+
+  - type: input
+    attributes:
+      label: Bug Timeline
+      description: Is this a new bug or an old issue? When did it first start?
+
+  - type: textarea
+    attributes:
+      label: Expected behavior
+      description: >-
+        What did you expect to happen?
+      placeholder: I expected it to move left.
+
+  - type: textarea
+    attributes:
+      label: Actual behavior
+      description: What actually happened instead?
+      placeholder: It moved right instead of left.
+
+  - type: textarea
+    attributes:
+      label: Steps to Reproduce
+      description: >-
+        Please describe the steps needed to reproduce the issue.
+      placeholder: |
+        1. [First Step] ...
+        2. [Second Step] ...
+        3. [and so on] ...
+
+  - type: markdown
+    attributes:
+      value: |
+        # Your Setup
+
+  - type: input
+    attributes:
+      label: Version of Marlin Firmware
+      description: "See the About Menu on the LCD or the output of `M115`. NOTE: For older releases we only patch critical bugs."
+    validations:
+      required: true
+
+  - type: input
+    attributes:
+      label: Printer model
+      description: Creality Ender 3, Prusa mini, or Kossel Delta?
+
+  - type: input
+    attributes:
+      label: Electronics
+      description: Stock electronics, upgrade board, or something else?
+
+  - type: input
+    attributes:
+      label: Add-ons
+      description: Please list any hardware add-ons that could be involved.
+
+  - type: dropdown
+    attributes:
+      label: Bed Leveling
+      description: What kind of bed leveling compensation are you using?
+      options:
+        - UBL Bilinear mesh
+        - ABL Bilinear mesh
+        - ABL Linear grid
+        - ABL 3-point
+        - MBL Manual Bed Leveling
+        - No Bed Leveling
+
+  - type: dropdown
+    attributes:
+      label: Your Slicer
+      description: Do you use Slic3r, Prusa Slicer, Simplify3D, IdeaMaker...?
+      options:
+        - Slic3r
+        - Simplify3D
+        - Prusa Slicer
+        - IdeaMaker
+        - Cura
+        - Other (explain below)
+
+  - type: dropdown
+    attributes:
+      label: Host Software
+      description: Do you use OctoPrint, Repetier Host, Pronterface...?
+      options:
+        - SD Card (headless)
+        - Repetier Host
+        - OctoPrint
+        - Pronterface
+        - Cura
+        - Same as my slicer
+        - Other (explain below)
+
+  - type: markdown
+    attributes:
+      value: >-
+        ## Other things to include
+
+        Please also be sure to include these items to help with troubleshooting:
+
+          * **A ZIP file** containing your `Configuration.h` and `Configuration_adv.h`.
+            (Please don't paste lengthy configuration text here.)
+          * **Log output** from the host. (`M111 S247` for maximum logging.)
+          * **Images or videos** demonstrating the problem, if it helps to make it clear.
+          * **A G-Code file** that exposes the problem, if not affecting _all_ G-code.
+
+        If you've made any other modifications to the firmware, please describe them in detail in the space provided.
+
+        When pasting formatted text into the box below don't forget to put ` ``` ` (on its own line) before and after to make it readable.
+
+  - type: textarea
+    attributes:
+      label: Additional information & file uploads
@@ -1,17 +1,20 @@
 blank_issues_enabled: false
 contact_links:
-  - name: Marlin Documentation
-    url: http://marlinfw.org/
+  - name: 📖 Marlin Documentation
+    url: https://marlinfw.org/
    about: Lots of documentation on installing and using Marlin.
-  - name: MarlinFirmware Facebook group
+  - name: 👤 MarlinFirmware Facebook group
    url: https://www.facebook.com/groups/1049718498464482
    about: Please ask and answer questions here.
-  - name: Marlin on Discord
+  - name: 🕹 Marlin on Discord
    url: https://discord.gg/n5NJ59y
    about: Join the Discord server for support and discussion.
-  - name: Marlin Discussion Forum
-    url: http://forums.reprap.org/list.php?415
+  - name: 🔗 Marlin Discussion Forum
+    url: https://reprap.org/forum/list.php?415
    about: A searchable web forum hosted by RepRap dot org.
-  - name: Marlin Videos on YouTube
+  - name: 📺 Marlin Videos on YouTube
    url: https://www.youtube.com/results?search_query=marlin+firmware
    about: Tutorials and more from Marlin users all around the world. Great for new users!
+  - name: 💸 Want to donate?
+    url: https://www.thinkyhead.com/donate-to-marlin
+    about: Please take a look at the various options to support Marlin Firmware's development financially!
@@ -1,35 +0,0 @@
---
-name: Feature request
-about: Request a Feature
-title: "[FR] (feature request title)"
-labels: ''
-assignees: ''
-
---
-
-<!--
-
-Have you read Marlin's Code of Conduct? By filing an Issue, you are expected to comply with it, including treating everyone with respect: https://github.com/MarlinFirmware/Marlin/blob/master/.github/code_of_conduct.md
-
-Do you want to ask a question? Are you looking for support? Please don't post here. Instead please use one of the support links at https://github.com/MarlinFirmware/Marlin/issues/new/choose
-
-Before filing an issue be sure to test the "bugfix" branches to see whether the issue has been resolved.
-
-->
-
-### Description
-
-<!-- Description of the requested feature -->
-
-### Feature Workflow
-
-<!-- Please describe the feature's behavior, user interaction, etc. -->
-
-1. [First Action]
-2. [Second Action]
-3. [and so on...]
-
-#### Additional Information
-
-* Provide pictures or links that demonstrate a similar feature or concept.
-* See [How Can I Contribute](#how-can-i-contribute) for additional guidelines.
@@ -0,0 +1,44 @@
+name: ✨ Request a feature
+description: Request a new Marlin Firmware feature
+title: "[FR] (feature summary)"
+labels: 'T: Feature Request'
+body:
+  - type: markdown
+    attributes:
+      value: >
+        Do you want to ask a question? Are you looking for support? Please use one of the [support links](https://github.com/MarlinFirmware/Marlin/issues/new/choose).
+
+  - type: markdown
+    attributes:
+      value: >
+        **Thank you for requesting a new Marlin Firmware feature!**
+
+        ## Before Requesting a Feature
+
+        - Read and understand Marlin's [Code of Conduct](https://github.com/MarlinFirmware/Marlin/blob/master/.github/code_of_conduct.md). You are expected to comply with it, including treating everyone with respect.
+
+        - Check the latest [`bugfix-2.0.x` branch](https://github.com/MarlinFirmware/Marlin/archive/bugfix-2.0.x.zip) to see if the feature already exists.
+
+        - Before you proceed with your request, please consider if it is necessary to make it into a firmware feature, or if it may be better suited for a slicer or host feature.
+
+  - type: textarea
+    attributes:
+      label: Is your feature request related to a problem? Please describe.
+      description: A clear description of the problem (e.g., "I need X but Marlin can't do it [...]").
+
+  - type: textarea
+    attributes:
+      label: Are you looking for hardware support?
+      description: Tell us the printer, board, or peripheral that needs support.
+
+  - type: textarea
+    attributes:
+      label: Describe the feature you want
+      description: A clear description of the feature and how you think it should work.
+    validations:
+      required: true
+
+  - type: textarea
+    attributes:
+      label: Additional context
+      description: Add any other context or screenshots about the feature request here.
@@ -50,13 +50,13 @@ If chat is more your speed, you can join the MarlinFirmware Discord server:

 This section guides you through submitting a Bug Report for Marlin. Following these guidelines helps maintainers and the community understand your report, reproduce the behavior, and find related reports.

-Before creating a Bug Report, please test the "nightly" development branch, as you might find out that you don't need to create one. When you are creating a Bug Report, please [include as many details as possible](#how-do-i-submit-a-good-bug-report). Fill out [the required template](issue_template.md), the information it asks for helps us resolve issues faster.
+Before creating a Bug Report, please test the "nightly" development branch, as you might find out that you don't need to create one. When you are creating a Bug Report, please [include as many details as possible](#how-do-i-submit-a-good-bug-report). Fill out [the required template](ISSUE_TEMPLATE/bug_report.yml), the information it asks for helps us resolve issues faster.

 > **Note:** Regressions can happen. If you find a **Closed** issue that seems like your issue, go ahead and open a new issue and include a link to the original issue in the body of your new one. All you need to create a link is the issue number, preceded by #. For example, #8888.

 #### How Do I Submit A (Good) Bug Report?

-Bugs are tracked as [GitHub issues](https://guides.github.com/features/issues/). Use the New Issue button to create an issue and provide the following information by filling in [the template](issue_template.md).
+Bugs are tracked as [GitHub issues](https://guides.github.com/features/issues/). Use the New Issue button to create an issue and provide the following information by filling in [the template](ISSUE_TEMPLATE/bug_report.yml).

 Explain the problem and include additional details to help maintainers reproduce the problem:

@@ -88,12 +88,12 @@ Include details about your configuration and environment:

 This section guides you through submitting a suggestion for Marlin, including completely new features and minor improvements to existing functionality. Following these guidelines helps maintainers and the community understand your suggestion and find related suggestions.

-Before creating a suggestion, please check [this list](#before-submitting-a-suggestion) as you might find out that you don't need to create one. When you are creating an enhancement suggestion, please [include as many details as possible](#how-do-i-submit-a-good-enhancement-suggestion). Fill in [the template](issue_template.md), including the steps that you imagine you would take if the feature you're requesting existed.
+Before creating a suggestion, please check [this list](https://github.com/MarlinFirmware/Marlin/issues?q=is%3Aopen+is%3Aissue+label%3A%22T%3A+Feature+Request%22) as you might find out that you don't need to create one. When you are creating an enhancement suggestion, please [include as many details as possible](#how-do-i-submit-a-good-feature-request). Fill in [the template](ISSUE_TEMPLATE/feature_request.yml), including the steps that you imagine you would take if the feature you're requesting existed.

 #### Before Submitting a Feature Request

 * **Check the [Marlin website](https://marlinfw.org/)** for tips — you might discover that the feature is already included. Most importantly, check if you're using [the latest version of Marlin](https://github.com/MarlinFirmware/Marlin/releases) and if you can get the desired behavior by changing [Marlin's config settings](https://marlinfw.org/docs/configuration/configuration.html).
-* **Perform a [cursory search](https://github.com/MarlinFirmware/Marlin/issues?q=is%3Aissue)** to see if the enhancement has already been suggested. If it has, add a comment to the existing issue instead of opening a new one.
+* **Perform a [cursory search](https://github.com/MarlinFirmware/Marlin/issues?q=is%3Aopen+is%3Aissue+label%3A%22T%3A+Feature+Request%22)** to see if the enhancement has already been suggested. If it has, add a comment to the existing issue instead of opening a new one.

 #### How Do I Submit A (Good) Feature Request?

@@ -116,7 +116,7 @@ Unsure where to begin contributing to Marlin? You can start by looking through t

 ### Pull Requests

-Pull Requests should always be targeted to working branches (e.g., `bugfix-1.1.x` and/or `bugfix-2.0.x`) and never to release branches (e.g., `1.1.x`). If this is your first Pull Request, please read our [Guide to Pull Requests](https://marlinfw.org/docs/development/getting_started_pull_requests.html) and Github's [Pull Request](https://help.github.com/articles/creating-a-pull-request/) documentation.
+Pull Requests should always be targeted to working branches (e.g., `bugfix-2.0.x` and/or `bugfix-1.1.x`) and never to release branches (e.g., `2.0.x` and/or `1.1.x`). If this is your first Pull Request, please read our [Guide to Pull Requests](https://marlinfw.org/docs/development/getting_started_pull_requests.html) and Github's [Pull Request](https://help.github.com/articles/creating-a-pull-request/) documentation.

 * Fill in [the required template](pull_request_template.md).
 * Don't include issue numbers in the PR title.
@@ -1,35 +0,0 @@
-<!--
-
-Have you read Marlin's Code of Conduct? By filing an Issue, you are expected to comply with it, including treating everyone with respect: https://github.com/MarlinFirmware/Marlin/blob/bugfix-2.0.x/.github/code_of_conduct.md
-
-Do you want to ask a question? Are you looking for support? Please don't post here. Instead use one of the following options:
-
- The Marlin Firmware forum at https://reprap.org/forum/list.php?415
- The MarlinFirmware Facebook Group at https://www.facebook.com/groups/1049718498464482/
- The MarlinFirmware Discord Server at https://discord.gg/n5NJ59y.
-
-Before filing an issue be sure to test the latest "bugfix" branch to see whether the issue is already addressed.
-
-->
-
-### Description
-
-<!-- Description of the bug or requested feature -->
-
-### Steps to Reproduce
-
-<!-- If this is a Bug Report, please describe the steps needed to reproduce the issue -->
-
-1. [First Step]
-2. [Second Step]
-3. [and so on...]
-
-**Expected behavior:** [What you expect to happen]
-
-**Actual behavior:** [What actually happens]
-
-#### Additional Information
-
-* Include a ZIP file containing your `Configuration.h` and `Configuration_adv.h` files.
-* Provide pictures or links to videos that clearly demonstrate the issue.
-* See [How Can I Contribute](#how-can-i-contribute) for additional guidelines.
@@ -1,23 +1,33 @@
-### Requirements
+<!--

-* Filling out this template is required. Pull Requests without a clear description may be closed at the maintainers' discretion.
+Submitting a Pull Request
+
+- Please fill out all sections of this form. You can delete the helpful comments.
+- Pull Requests without clear information will take longer and may even be rejected.
+- We get a high volume of submissions so please be patient during review.
+
+-->

 ### Description

 <!--

-We must be able to understand your proposed change from this description. If we can't understand what the code will do from this description, the Pull Request may be closed at the maintainers' discretion. Keep in mind that the maintainer reviewing this PR may not be familiar with or have worked with the code recently, so please walk us through the concepts.
+Clearly describe the submitted changes with lots of details. Include images where helpful. Initial reviewers may not be familiar with the subject, so be as thorough as possible. You can use MarkDown syntax to improve readability with bullet lists, code blocks, and so on. PREVIEW and fix up formatting before submitting.

 -->

+### Requirements
+
+<!-- Does this PR require a specific board, LCD, etc.? -->
+
 ### Benefits

-<!-- What does this fix or improve? -->
+<!-- What does this PR fix or improve? -->

 ### Configurations

-<!-- Attach any Configuration.h, Configuration_adv.h, or platformio.ini files needed to compile/test your Pull Request. -->
+<!-- Attach Configurations ZIP and any other files needed to test this PR. -->

 ### Related Issues

-<!-- Whether this fixes a bug or fulfills a feature request, please list any related Issues here. -->
+<!-- Does this PR fix a bug or fulfill a Feature Request? Link related Issues here. -->
@@ -1,7 +0,0 @@
-Thanks for your contribution! Unfortunately we can't accept PRs directed at release branches. We make patches to the bugfix branches and only later do we push them out as releases.
-
-Please redo this PR starting with the `bugfix-2.0.x` branch and be careful to target `bugfix-2.0.x` when resubmitting the PR.
-
-It may help to set your fork's default branch to `bugfix-2.0.x`.
-
-See [this page](http://marlinfw.org/docs/development/getting_started_pull_requests.html) for full instructions.
@@ -7,10 +7,12 @@ name: Bump Distribution Date

 on:
  schedule:
-    - cron: '0 0 * * *'
+    - cron: '0 */6 * * *'

 jobs:
  bump_date:
+    name: Bump Distribution Date
+    if: github.repository == 'MarlinFirmware/Marlin'

    runs-on: ubuntu-latest

@@ -24,11 +26,14 @@ jobs:
    - name: Bump Distribution Date
      run: |
        # Inline Bump Script
-        [[ "$GITHUB_REPOSITORY" == "MarlinFirmware/Marlin" ]] || exit 0
-        DIST=$( date +"%Y-%m-%d" )
-        eval "sed -E -i 's/(#define +STRING_DISTRIBUTION_DATE) .*$/\1 \"$DIST\"/g' Marlin/src/inc/Version.h" && \
-        git config user.name "${GITHUB_ACTOR}" && \
-        git config user.email "${GITHUB_ACTOR}@users.noreply.github.com" && \
-        git add . && \
-        git commit -m "[cron] Bump distribution date ($DIST)" && \
-        git push
+        if [[ ! "$( git log -1 --pretty=%B )" =~ ^\[cron\] ]]; then
+          DIST=$( date +"%Y-%m-%d" )
+          eval "sed -E -i 's/(#define +STRING_DISTRIBUTION_DATE) .*$/\1 \"$DIST\"/g' Marlin/src/inc/Version.h" && \
+          eval "sed -E -i 's/(#define +STRING_DISTRIBUTION_DATE) .*$/\1 \"$DIST\"/g' Marlin/Version.h" && \
+          git config user.name "${GITHUB_ACTOR}" && \
+          git config user.email "${GITHUB_ACTOR}@users.noreply.github.com" && \
+          git add . && \
+          git commit -m "[cron] Bump distribution date ($DIST)" && \
+          git push
+        fi
+        exit 0
@@ -1,12 +1,13 @@
 #
-# comment-pr.yml
-# Add a comment to any PR directed to a release branch
+# check-pr.yml
+# Close PRs directed at release branches
 #

 name: PR Bad Target

 on:
-  pull_request:
+  pull_request_target:
+    types: [opened]
    branches:
    - 1.0.x
    - 1.1.x
@@ -14,14 +15,19 @@ on:

 jobs:
  bad_target:
-
    name: PR Bad Target
+    if: github.repository == 'MarlinFirmware/Marlin'
+
    runs-on: ubuntu-latest

    steps:
-      - uses: actions/checkout@v1
-      - uses: harupy/comment-on-pr@master
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        with:
-          filename: bad-target.md
+    - uses: superbrothers/close-pull-request@v3
+      with:
+        comment: >
+          Thanks for your contribution! Unfortunately we can't accept PRs directed at release branches. We make patches to the bugfix branches and only later do we push them out as releases.
+
+          Please redo this PR starting with the `bugfix-2.0.x` branch and be careful to target `bugfix-2.0.x` when resubmitting the PR.
+
+          It may help to set your fork's default branch to `bugfix-2.0.x`.
+
+          See [this page](http://marlinfw.org/docs/development/getting_started_pull_requests.html) for full instructions.
@@ -0,0 +1,39 @@
+#
+# clean-closed.yml
+# Remove obsolete labels when an Issue or PR is closed
+#
+
+name: Clean Closed
+
+on:
+  pull_request:
+    types: [closed]
+  issues:
+    types: [closed]
+
+jobs:
+  remove_label:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        label:
+          - "S: Don't Merge"
+          - "S: Hold for 2.1"
+          - "S: Please Merge"
+          - "S: Please Test"
+          - "help wanted"
+          - "Needs: Discussion"
+          - "Needs: Documentation"
+          - "Needs: More Data"
+          - "Needs: Patch"
+          - "Needs: Testing"
+          - "Needs: Work"
+
+    steps:
+      - uses: actions/checkout@v2
+      - name: Remove Labels
+        uses: actions-ecosystem/action-remove-labels@v1
+        with:
+          github_token: ${{ github.token }}
+          labels: ${{ matrix.label }}
@@ -0,0 +1,28 @@
+#
+# close-stale.yml
+# Close open issues after a period of inactivity
+#
+
+name: Close Stale Issues
+
+on:
+  schedule:
+  - cron: "22 1 * * *"
+
+jobs:
+  stale:
+    name: Close Stale Issues
+    if: github.repository == 'MarlinFirmware/Marlin'
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/stale@v3
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+        stale-issue-message: 'This issue has had no activity in the last 60 days. Please add a reply if you want to keep this issue active, otherwise it will be automatically closed within 10 days.'
+        days-before-stale: 60
+        days-before-close: 10
+        stale-issue-label: 'stale-closing-soon'
+        exempt-all-assignees: true
+        exempt-issue-labels: 'Bug: Confirmed !,T: Feature Request,Needs: Discussion,Needs: Documentation,Needs: Patch,Needs: Work,Needs: Testing,help wanted,no-locking'
@@ -0,0 +1,32 @@
+#
+# lock-closed.yml
+# Lock closed issues after a period of inactivity
+#
+
+name: Lock Closed Issues
+
+on:
+  schedule:
+    - cron: '0 1/13 * * *'
+
+jobs:
+  lock:
+    name: Lock Closed Issues
+    if: github.repository == 'MarlinFirmware/Marlin'
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: dessant/lock-threads@v2
+      with:
+        github-token: ${{ github.token }}
+        process-only: 'issues'
+        issue-lock-inactive-days: '60'
+        issue-exclude-created-before: ''
+        issue-exclude-labels: 'no-locking'
+        issue-lock-labels: ''
+        issue-lock-comment: >
+          This issue has been automatically locked since there
+          has not been any recent activity after it was closed.
+          Please open a new issue for related bugs.
+        issue-lock-reason: ''
@@ -59,14 +59,14 @@ jobs:
        #- STM32F103RC_btt_maple
        - STM32F103RC_btt_USB_maple
        - STM32F103RC_fysetc_maple
-        - STM32F103RC_meeb
+        - STM32F103RC_meeb_maple
        - jgaurora_a5s_a1_maple
        - STM32F103VE_longer_maple
        #- mks_robin_maple
        - mks_robin_lite_maple
        - mks_robin_pro_maple
        #- mks_robin_nano35_maple
-        #- STM32F103RET6_creality_maple
+        #- STM32F103RE_creality_maple
        - STM32F103VE_ZM3E4V2_USB_maple

        # STM32 (ST) Environments
@@ -75,7 +75,8 @@ jobs:
        #- STM32F103RC_btt_USB
        - STM32F103RE_btt
        - STM32F103RE_btt_USB
-        - STM32F103RET6_creality
+        - STM32F103RE_creality
+        - STM32F401RC_creality
        - STM32F103VE_longer
        - STM32F407VE_black
        - STM32F401VE_STEVAL
@@ -97,6 +98,7 @@ jobs:
        - REMRAM_V1
        - BTT_SKR_SE_BX
        - chitu_f103
+        - Index_Mobo_Rev03

        # Put lengthy tests last

@@ -112,10 +114,10 @@ jobs:
    steps:

    - name: Check out the PR
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3

    - name: Cache pip
-      uses: actions/cache@v2
+      uses: actions/cache@v3
      with:
        path: ~/.cache/pip
        key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
@@ -123,21 +125,22 @@ jobs:
          ${{ runner.os }}-pip-

    - name: Cache PlatformIO
-      uses: actions/cache@v2
+      uses: actions/cache@v3
      with:
        path: ~/.platformio
        key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}

    - name: Select Python 3.7
-      uses: actions/setup-python@v2
+      uses: actions/setup-python@v3
      with:
        python-version: '3.7' # Version range or exact version of a Python version to use, using semvers version range syntax.
        architecture: 'x64' # optional x64 or x86. Defaults to x64 if not specified

    - name: Install PlatformIO
      run: |
-        pip install -U https://github.com/platformio/platformio-core/archive/develop.zip
-        platformio update
+        pip install -U platformio
+        pio upgrade --dev
+        pio pkg update --global

    - name: Run ${{ matrix.test-platform }} Tests
      run: |
@@ -0,0 +1,22 @@
+#
+# unlock-reopened.yml
+# Unlock an issue whenever it is re-opened
+#
+
+name: "Unlock reopened issue"
+
+on:
+  issues:
+    types: [reopened]
+
+jobs:
+  unlock:
+    name: Unlock Reopened
+    if: github.repository == 'MarlinFirmware/Marlin'
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: OSDKDev/unlock-issues@v1.1
+      with:
+        repo-token: "${{ secrets.GITHUB_TOKEN }}"
@@ -22,12 +22,16 @@
 # Generated files
 _Version.h
 bdf2u8g
+marlin_config.json
+mczip.h
+*.gen
+*.sublime-workspace

 #
 # OS
 #
 applet/
-*.DS_Store
+.DS_Store

 #
 # Misc
@@ -37,7 +41,6 @@ applet/
 *.rej
 *.bak
 *.idea
-*.s
 *.i
 *.ii
 *.swp
@@ -137,20 +140,19 @@ __vm/
 vc-fileutils.settings

 # Visual Studio Code
-.vscode
-.vscode/.browse.c_cpp.db*
-.vscode/c_cpp_properties.json
-.vscode/launch.json
-.vscode/*.db
+.vscode/*
+!.vscode/extensions.json

 #Simulation
 imgui.ini
 eeprom.dat
+spi_flash.bin

 #cmake
 CMakeLists.txt
 src/CMakeLists.txt
 CMakeListsPrivate.txt
+build/

 # CLion
 cmake-build-*
@@ -167,7 +169,3 @@ __pycache__

 # IOLogger logs
 *_log.csv
-
-# Simulation / Native
-eeprom.dat
-imgui.ini
@@ -0,0 +1,11 @@
+{
+    // See http://go.microsoft.com/fwlink/?LinkId=827846
+    // for the documentation about the extensions.json format
+    "recommendations": [
+        "marlinfirmware.auto-build",
+        "platformio.platformio-ide"
+    ],
+    "unwantedRecommendations": [
+        "ms-vscode.cpptools-extension-pack"
+    ]
+}
@@ -132,7 +132,7 @@ CC_MIN:=$(shell $(CC) -dM -E - < /dev/null | grep __GNUC_MINOR__ | cut -f3 -d\ )
 CC_PATCHLEVEL:=$(shell $(CC) -dM -E - < /dev/null | grep __GNUC_PATCHLEVEL__ | cut -f3 -d\ )
 CC_VER:=$(shell echo $$(( $(CC_MAJ) * 10000 + $(CC_MIN) * 100 + $(CC_PATCHLEVEL) )))
 ifeq ($(shell test $(CC_VER) -lt 40901 && echo 1),1)
-  @echo This version of GCC is likely broken. Enabling relocation workaround.
+  $(warning This GCC version $(CC_VER) is likely broken. Enabling relocation workaround.)
  RELOC_WORKAROUND = 1
 endif

@@ -191,6 +191,134 @@ else ifeq ($(HARDWARE_MOTHERBOARD),1034)
 # RAMPS Derivatives - ATmega1280, ATmega2560
 #

+# 3Drag Controller
+else ifeq ($(HARDWARE_MOTHERBOARD),1100)
+# Velleman K8200 Controller (derived from 3Drag Controller)
+else ifeq ($(HARDWARE_MOTHERBOARD),1101)
+# Velleman K8400 Controller (derived from 3Drag Controller)
+else ifeq ($(HARDWARE_MOTHERBOARD),1102)
+# Velleman K8600 Controller (Vertex Nano)
+else ifeq ($(HARDWARE_MOTHERBOARD),1103)
+# Velleman K8800 Controller (Vertex Delta)
+else ifeq ($(HARDWARE_MOTHERBOARD),1104)
+# 2PrintBeta BAM&DICE with STK drivers
+else ifeq ($(HARDWARE_MOTHERBOARD),1105)
+# 2PrintBeta BAM&DICE Due with STK drivers
+else ifeq ($(HARDWARE_MOTHERBOARD),1106)
+# MKS BASE v1.0
+else ifeq ($(HARDWARE_MOTHERBOARD),1107)
+# MKS BASE v1.4 with Allegro A4982 stepper drivers
+else ifeq ($(HARDWARE_MOTHERBOARD),1108)
+# MKS BASE v1.5 with Allegro A4982 stepper drivers
+else ifeq ($(HARDWARE_MOTHERBOARD),1109)
+# MKS BASE v1.6 with Allegro A4982 stepper drivers
+else ifeq ($(HARDWARE_MOTHERBOARD),1110)
+# MKS BASE 1.0 with Heroic HR4982 stepper drivers
+else ifeq ($(HARDWARE_MOTHERBOARD),1111)
+# MKS GEN v1.3 or 1.4
+else ifeq ($(HARDWARE_MOTHERBOARD),1112)
+# MKS GEN L
+else ifeq ($(HARDWARE_MOTHERBOARD),1113)
+# BigTreeTech or BIQU KFB2.0
+else ifeq ($(HARDWARE_MOTHERBOARD),1114)
+# zrib V2.0 (Chinese RAMPS replica)
+else ifeq ($(HARDWARE_MOTHERBOARD),1115)
+# zrib V5.2 (Chinese RAMPS replica)
+else ifeq ($(HARDWARE_MOTHERBOARD),1116)
+# Felix 2.0+ Electronics Board (RAMPS like)
+else ifeq ($(HARDWARE_MOTHERBOARD),1117)
+# Invent-A-Part RigidBoard
+else ifeq ($(HARDWARE_MOTHERBOARD),1118)
+# Invent-A-Part RigidBoard V2
+else ifeq ($(HARDWARE_MOTHERBOARD),1119)
+# Sainsmart 2-in-1 board
+else ifeq ($(HARDWARE_MOTHERBOARD),1120)
+# Ultimaker
+else ifeq ($(HARDWARE_MOTHERBOARD),1121)
+# Ultimaker (Older electronics. Pre 1.5.4. This is rare)
+else ifeq ($(HARDWARE_MOTHERBOARD),1122)
+  MCU              ?= atmega1280
+  PROG_MCU         ?= m1280
+# Azteeg X3
+else ifeq ($(HARDWARE_MOTHERBOARD),1123)
+# Azteeg X3 Pro
+else ifeq ($(HARDWARE_MOTHERBOARD),1124)
+# Ultimainboard 2.x (Uses TEMP_SENSOR 20)
+else ifeq ($(HARDWARE_MOTHERBOARD),1125)
+# Rumba
+else ifeq ($(HARDWARE_MOTHERBOARD),1126)
+# Raise3D N series Rumba derivative
+else ifeq ($(HARDWARE_MOTHERBOARD),1127)
+# Rapide Lite 200 (v1, low-cost RUMBA clone with drv)
+else ifeq ($(HARDWARE_MOTHERBOARD),1128)
+# Formbot T-Rex 2 Plus
+else ifeq ($(HARDWARE_MOTHERBOARD),1129)
+# Formbot T-Rex 3
+else ifeq ($(HARDWARE_MOTHERBOARD),1130)
+# Formbot Raptor
+else ifeq ($(HARDWARE_MOTHERBOARD),1131)
+# Formbot Raptor 2
+else ifeq ($(HARDWARE_MOTHERBOARD),1132)
+# bq ZUM Mega 3D
+else ifeq ($(HARDWARE_MOTHERBOARD),1133)
+# MakeBoard Mini v2.1.2 by MicroMake
+else ifeq ($(HARDWARE_MOTHERBOARD),1134)
+# TriGorilla Anycubic version 1.3-based on RAMPS EFB
+else ifeq ($(HARDWARE_MOTHERBOARD),1135)
+#   ... Ver 1.4
+else ifeq ($(HARDWARE_MOTHERBOARD),1136)
+#   ... Rev 1.1 (new servo pin order)
+else ifeq ($(HARDWARE_MOTHERBOARD),1137)
+# Creality: Ender-4, CR-8
+else ifeq ($(HARDWARE_MOTHERBOARD),1138)
+# Creality: CR10S, CR20, CR-X
+else ifeq ($(HARDWARE_MOTHERBOARD),1139)
+# Dagoma F5
+else ifeq ($(HARDWARE_MOTHERBOARD),1140)
+# FYSETC F6 1.3
+else ifeq ($(HARDWARE_MOTHERBOARD),1141)
+# FYSETC F6 1.4
+else ifeq ($(HARDWARE_MOTHERBOARD),1142)
+# Wanhao Duplicator i3 Plus
+else ifeq ($(HARDWARE_MOTHERBOARD),1143)
+# VORON Design
+else ifeq ($(HARDWARE_MOTHERBOARD),1144)
+# Tronxy TRONXY-V3-1.0
+else ifeq ($(HARDWARE_MOTHERBOARD),1145)
+# Z-Bolt X Series
+else ifeq ($(HARDWARE_MOTHERBOARD),1146)
+# TT OSCAR
+else ifeq ($(HARDWARE_MOTHERBOARD),1147)
+# Overlord/Overlord Pro
+else ifeq ($(HARDWARE_MOTHERBOARD),1148)
+# ADIMLab Gantry v1
+else ifeq ($(HARDWARE_MOTHERBOARD),1149)
+# ADIMLab Gantry v2
+else ifeq ($(HARDWARE_MOTHERBOARD),1150)
+# BIQU Tango V1
+else ifeq ($(HARDWARE_MOTHERBOARD),1151)
+# MKS GEN L V2
+else ifeq ($(HARDWARE_MOTHERBOARD),1152)
+# MKS GEN L V2.1
+else ifeq ($(HARDWARE_MOTHERBOARD),1153)
+# Copymaster 3D
+else ifeq ($(HARDWARE_MOTHERBOARD),1154)
+# Ortur 4
+else ifeq ($(HARDWARE_MOTHERBOARD),1155)
+# Tenlog D3 Hero IDEX printer
+else ifeq ($(HARDWARE_MOTHERBOARD),1156)
+# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend0, Hotend1, Fan, Bed)
+else ifeq ($(HARDWARE_MOTHERBOARD),1157)
+# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend0, Hotend1, Hotend2, Bed)
+else ifeq ($(HARDWARE_MOTHERBOARD),1158)
+# Ramps S 1.2 by Sakul.cz (Power outputs: Hotend, Fan0, Fan1, Bed)
+else ifeq ($(HARDWARE_MOTHERBOARD),1159)
+# Longer LK1 PRO / Alfawise U20 Pro (PRO version)
+else ifeq ($(HARDWARE_MOTHERBOARD),1160)
+# Longer LKx PRO / Alfawise Uxx Pro (PRO version)
+else ifeq ($(HARDWARE_MOTHERBOARD),1161)
+
+
 # 3Drag Controller
 else ifeq ($(HARDWARE_MOTHERBOARD),1100)
 # Velleman K8200 Controller (derived from 3Drag Controller)
@@ -358,20 +486,38 @@ else ifeq ($(HARDWARE_MOTHERBOARD),1311)
 else ifeq ($(HARDWARE_MOTHERBOARD),1312)
 # Mega controller
 else ifeq ($(HARDWARE_MOTHERBOARD),1313)
-# Geeetech GT2560 Rev B for Mecreator2
+# Geeetech GT2560 Rev A
 else ifeq ($(HARDWARE_MOTHERBOARD),1314)
-# Geeetech GT2560 Rev. A
+# Geeetech GT2560 Rev A+ (with auto level probe)
 else ifeq ($(HARDWARE_MOTHERBOARD),1315)
-# Geeetech GT2560 Rev. A+ (with auto level probe)
+# Geeetech GT2560 Rev B
 else ifeq ($(HARDWARE_MOTHERBOARD),1316)
-# Geeetech GT2560 Rev B for A10(M/D)
+# Geeetech GT2560 Rev B for A10(M/T/D)
 else ifeq ($(HARDWARE_MOTHERBOARD),1317)
-# Geeetech GT2560 Rev B for A20(M/D)
+# Geeetech GT2560 Rev B for A10(M/T/D)
 else ifeq ($(HARDWARE_MOTHERBOARD),1318)
-# Einstart retrofit
+# Geeetech GT2560 Rev B for Mecreator2
 else ifeq ($(HARDWARE_MOTHERBOARD),1319)
-# Wanhao 0ne+ i3 Mini
+# Geeetech GT2560 Rev B for A20(M/T/D)
 else ifeq ($(HARDWARE_MOTHERBOARD),1320)
+# Einstart retrofit
+else ifeq ($(HARDWARE_MOTHERBOARD),1321)
+# Wanhao 0ne+ i3 Mini
+else ifeq ($(HARDWARE_MOTHERBOARD),1322)
+# Leapfrog Xeed 2015
+else ifeq ($(HARDWARE_MOTHERBOARD),1323)
+# PICA Shield (original version)
+else ifeq ($(HARDWARE_MOTHERBOARD),1324)
+# PICA Shield (rev C or later)
+else ifeq ($(HARDWARE_MOTHERBOARD),1325)
+# Intamsys 4.0 (Funmat HT)
+else ifeq ($(HARDWARE_MOTHERBOARD),1326)
+# Malyan M180 Mainboard Version 2 (no display function, direct gcode only)
+else ifeq ($(HARDWARE_MOTHERBOARD),1327)
+# Geeetech GT2560 Rev B for A20(M/T/D)
+else ifeq ($(HARDWARE_MOTHERBOARD),1328)
+# Mega controller & Protoneer CNC Shield V3.00
+else ifeq ($(HARDWARE_MOTHERBOARD),1329)

 #
 # ATmega1281, ATmega2561
@@ -445,6 +591,11 @@ else ifeq ($(HARDWARE_MOTHERBOARD),1510)
  HARDWARE_VARIANT ?= Sanguino
  MCU              ?= atmega1284p
  PROG_MCU         ?= m1284p
+# ZoneStar ZMIB V2
+else ifeq ($(HARDWARE_MOTHERBOARD),1511)
+  HARDWARE_VARIANT ?= Sanguino
+  MCU              ?= atmega1284p
+  PROG_MCU         ?= m1284p

 #
 # Other ATmega644P, ATmega644, ATmega1284P
@@ -41,7 +41,7 @@
 * here we define this default string as the date where the latest release
 * version was tagged.
 */
-//#define STRING_DISTRIBUTION_DATE "2021-08-08"
+//#define STRING_DISTRIBUTION_DATE "2022-05-29"

 /**
 * Defines a generic printer name to be output to the LCD after booting Marlin.
@@ -23,6 +23,7 @@

 #include "../../inc/MarlinConfig.h"
 #include "HAL.h"
+#include <avr/wdt.h>

 #ifdef USBCON
  DefaultSerial1 MSerial0(false, Serial);
@@ -35,13 +36,32 @@
 // Public Variables
 // ------------------------

-//uint8_t MCUSR;
+// Don't initialize/override variable (which would happen in .init4)
+uint8_t MarlinHAL::reset_reason __attribute__((section(".noinit")));

 // ------------------------
 // Public functions
 // ------------------------

-void HAL_init() {
+__attribute__((naked))             // Don't output function pro- and epilogue
+__attribute__((used))              // Output the function, even if "not used"
+__attribute__((section(".init3"))) // Put in an early user definable section
+void save_reset_reason() {
+  #if ENABLED(OPTIBOOT_RESET_REASON)
+    __asm__ __volatile__(
+      A("STS %0, r2")
+      : "=m"(hal.reset_reason)
+    );
+  #else
+    hal.reset_reason = MCUSR;
+  #endif
+
+  // Clear within 16ms since WDRF bit enables a 16ms watchdog timer -> Boot loop
+  hal.clear_reset_source();
+  wdt_disable();
+}
+
+void MarlinHAL::init() {
  // Init Servo Pins
  #define INIT_SERVO(N) OUT_WRITE(SERVO##N##_PIN, LOW)
  #if HAS_SERVO_0
@@ -56,9 +76,11 @@ void HAL_init() {
  #if HAS_SERVO_3
    INIT_SERVO(3);
  #endif
+
+  init_pwm_timers();   // Init user timers to default frequency - 1000HZ
 }

-void HAL_reboot() {
+void MarlinHAL::reboot() {
  #if ENABLED(USE_WATCHDOG)
    while (1) { /* run out the watchdog */ }
  #else
@@ -67,6 +89,62 @@ void HAL_reboot() {
  #endif
 }

+// ------------------------
+// Watchdog Timer
+// ------------------------
+
+#if ENABLED(USE_WATCHDOG)
+
+  #include <avr/wdt.h>
+  #include "../../MarlinCore.h"
+
+  // Initialize watchdog with 8s timeout, if possible. Otherwise, make it 4s.
+  void MarlinHAL::watchdog_init() {
+    #if ENABLED(WATCHDOG_DURATION_8S) && defined(WDTO_8S)
+      #define WDTO_NS WDTO_8S
+    #else
+      #define WDTO_NS WDTO_4S
+    #endif
+    #if ENABLED(WATCHDOG_RESET_MANUAL)
+      // Enable the watchdog timer, but only for the interrupt.
+      // Take care, as this requires the correct order of operation, with interrupts disabled.
+      // See the datasheet of any AVR chip for details.
+      wdt_reset();
+      cli();
+      _WD_CONTROL_REG = _BV(_WD_CHANGE_BIT) | _BV(WDE);
+      _WD_CONTROL_REG = _BV(WDIE) | (WDTO_NS & 0x07) | ((WDTO_NS & 0x08) << 2); // WDTO_NS directly does not work. bit 0-2 are consecutive in the register but the highest value bit is at bit 5
+                                                                                // So worked for up to WDTO_2S
+      sei();
+      wdt_reset();
+    #else
+      wdt_enable(WDTO_NS); // The function handles the upper bit correct.
+    #endif
+    //delay(10000); // test it!
+  }
+
+  //===========================================================================
+  //=================================== ISR ===================================
+  //===========================================================================
+
+  // Watchdog timer interrupt, called if main program blocks >4sec and manual reset is enabled.
+  #if ENABLED(WATCHDOG_RESET_MANUAL)
+    ISR(WDT_vect) {
+      sei();  // With the interrupt driven serial we need to allow interrupts.
+      SERIAL_ERROR_MSG(STR_WATCHDOG_FIRED);
+      minkill();  // interrupt-safe final kill and infinite loop
+    }
+  #endif
+
+  // Reset watchdog. MUST be called at least every 4 seconds after the
+  // first watchdog_init or AVR will go into emergency procedures.
+  void MarlinHAL::watchdog_refresh() { wdt_reset(); }
+
+#endif // USE_WATCHDOG
+
+// ------------------------
+// Free Memory Accessor
+// ------------------------
+
 #if ENABLED(SDSUPPORT)

  #include "../../sd/SdFatUtil.h"
@@ -74,20 +152,20 @@ void HAL_reboot() {

 #else // !SDSUPPORT

-extern "C" {
-  extern char __bss_end;
-  extern char __heap_start;
-  extern void* __brkval;
+  extern "C" {
+    extern char __bss_end;
+    extern char __heap_start;
+    extern void* __brkval;

-  int freeMemory() {
-    int free_memory;
-    if ((int)__brkval == 0)
-      free_memory = ((int)&free_memory) - ((int)&__bss_end);
-    else
-      free_memory = ((int)&free_memory) - ((int)__brkval);
-    return free_memory;
+    int freeMemory() {
+      int free_memory;
+      if ((int)__brkval == 0)
+        free_memory = ((int)&free_memory) - ((int)&__bss_end);
+      else
+        free_memory = ((int)&free_memory) - ((int)__brkval);
+      return free_memory;
+    }
  }
-}

 #endif // !SDSUPPORT

@@ -19,16 +19,18 @@
 */
 #pragma once

+/**
+ * HAL for Arduino AVR
+ */
+
 #include "../shared/Marduino.h"
 #include "../shared/HAL_SPI.h"
 #include "fastio.h"
-#include "watchdog.h"
 #include "math.h"

 #ifdef USBCON
  #include <HardwareSerial.h>
 #else
-  #define HardwareSerial_h // Hack to prevent HardwareSerial.h header inclusion
  #include "MarlinSerial.h"
 #endif

@@ -39,6 +41,19 @@
 #include <avr/interrupt.h>
 #include <avr/io.h>

+//
+// Default graphical display delays
+//
+#if F_CPU >= 20000000
+  #define CPU_ST7920_DELAY_1 150
+  #define CPU_ST7920_DELAY_2   0
+  #define CPU_ST7920_DELAY_3 150
+#elif F_CPU == 16000000
+  #define CPU_ST7920_DELAY_1 125
+  #define CPU_ST7920_DELAY_2   0
+  #define CPU_ST7920_DELAY_3 188
+#endif
+
 #ifndef pgm_read_ptr
  // Compatibility for avr-libc 1.8.0-4.1 included with Ubuntu for
  // Windows Subsystem for Linux on Windows 10 as of 10/18/2019
@@ -61,9 +76,9 @@
  #define CRITICAL_SECTION_START()  unsigned char _sreg = SREG; cli()
  #define CRITICAL_SECTION_END()    SREG = _sreg
 #endif
-#define ISRS_ENABLED() TEST(SREG, SREG_I)
-#define ENABLE_ISRS()  sei()
-#define DISABLE_ISRS() cli()
+
+#define HAL_CAN_SET_PWM_FREQ   // This HAL supports PWM Frequency adjustment
+#define PWM_FREQUENCY 1000     // Default PWM frequency when set_pwm_duty() is called without set_pwm_frequency()

 // ------------------------
 // Types
@@ -71,16 +86,15 @@

 typedef int8_t pin_t;

-#define SHARED_SERVOS HAS_SERVOS
-#define HAL_SERVO_LIB Servo
+#define SHARED_SERVOS HAS_SERVOS  // Use shared/servos.cpp
+
+class Servo;
+typedef Servo hal_servo_t;

 // ------------------------
-// Public Variables
-// ------------------------
-
-//extern uint8_t MCUSR;
-
 // Serial ports
+// ------------------------
+
 #ifdef USBCON
  #include "../../core/serial_hook.h"
  typedef ForwardSerial1Class< decltype(Serial) > DefaultSerial1;
@@ -129,59 +143,15 @@ typedef int8_t pin_t;
  #endif
 #endif

-// ------------------------
-// Public functions
-// ------------------------
-
-void HAL_init();
-
-//void cli();
-
-//void _delay_ms(const int delay);
-
-inline void HAL_clear_reset_source() { MCUSR = 0; }
-inline uint8_t HAL_get_reset_source() { return MCUSR; }
-
-void HAL_reboot();
-
-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic push
-  #pragma GCC diagnostic ignored "-Wunused-function"
-#endif
-
-extern "C" int freeMemory();
-
-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic pop
-#endif
-
+//
 // ADC
-#ifdef DIDR2
-  #define HAL_ANALOG_SELECT(ind) do{ if (ind < 8) SBI(DIDR0, ind); else SBI(DIDR2, ind & 0x07); }while(0)
-#else
-  #define HAL_ANALOG_SELECT(ind) SBI(DIDR0, ind);
-#endif
-
-inline void HAL_adc_init() {
-  ADCSRA = _BV(ADEN) | _BV(ADSC) | _BV(ADIF) | 0x07;
-  DIDR0 = 0;
-  #ifdef DIDR2
-    DIDR2 = 0;
-  #endif
-}
-
-#define SET_ADMUX_ADCSRA(ch) ADMUX = _BV(REFS0) | (ch & 0x07); SBI(ADCSRA, ADSC)
-#ifdef MUX5
-  #define HAL_START_ADC(ch) if (ch > 7) ADCSRB = _BV(MUX5); else ADCSRB = 0; SET_ADMUX_ADCSRA(ch)
-#else
-  #define HAL_START_ADC(ch) ADCSRB = 0; SET_ADMUX_ADCSRA(ch)
-#endif
-
+//
 #define HAL_ADC_VREF        5.0
 #define HAL_ADC_RESOLUTION 10
-#define HAL_READ_ADC()  ADC
-#define HAL_ADC_READY() !TEST(ADCSRA, ADSC)

+//
+// Pin Mapping for M42, M43, M226
+//
 #define GET_PIN_MAP_PIN(index) index
 #define GET_PIN_MAP_INDEX(pin) pin
 #define PARSED_PIN_INDEX(code, dval) parser.intval(code, dval)
@@ -195,23 +165,113 @@ inline void HAL_adc_init() {
 // AVR compatibility
 #define strtof strtod

-#define HAL_CAN_SET_PWM_FREQ   // This HAL supports PWM Frequency adjustment
+// ------------------------
+// Free Memory Accessor
+// ------------------------

-/**
- *  set_pwm_frequency
- *  Sets the frequency of the timer corresponding to the provided pin
- *  as close as possible to the provided desired frequency. Internally
- *  calculates the required waveform generation mode, prescaler and
- *  resolution values required and sets the timer registers accordingly.
- *  NOTE that the frequency is applied to all pins on the timer (Ex OC3A, OC3B and OC3B)
- *  NOTE that there are limitations, particularly if using TIMER2. (see Configuration_adv.h -> FAST FAN PWM Settings)
- */
-void set_pwm_frequency(const pin_t pin, int f_desired);
+#pragma GCC diagnostic push
+#if GCC_VERSION <= 50000
+  #pragma GCC diagnostic ignored "-Wunused-function"
+#endif

-/**
- * set_pwm_duty
- *  Sets the PWM duty cycle of the provided pin to the provided value
- *  Optionally allows inverting the duty cycle [default = false]
- *  Optionally allows changing the maximum size of the provided value to enable finer PWM duty control [default = 255]
- */
-void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size=255, const bool invert=false);
+extern "C" int freeMemory();
+
+#pragma GCC diagnostic pop
+
+// ------------------------
+// MarlinHAL Class
+// ------------------------
+
+class MarlinHAL {
+public:
+
+  // Earliest possible init, before setup()
+  MarlinHAL() {}
+
+  // Watchdog
+  static void watchdog_init()    IF_DISABLED(USE_WATCHDOG, {});
+  static void watchdog_refresh() IF_DISABLED(USE_WATCHDOG, {});
+
+  static void init();          // Called early in setup()
+  static void init_board() {}  // Called less early in setup()
+  static void reboot();        // Restart the firmware from 0x0
+
+  // Interrupts
+  static bool isr_state() { return TEST(SREG, SREG_I); }
+  static void isr_on()  { sei(); }
+  static void isr_off() { cli(); }
+
+  static void delay_ms(const int ms) { _delay_ms(ms); }
+
+  // Tasks, called from idle()
+  static void idletask() {}
+
+  // Reset
+  static uint8_t reset_reason;
+  static uint8_t get_reset_source() { return reset_reason; }
+  static void clear_reset_source() { MCUSR = 0; }
+
+  // Free SRAM
+  static int freeMemory() { return ::freeMemory(); }
+
+  //
+  // ADC Methods
+  //
+
+  // Called by Temperature::init once at startup
+  static void adc_init() {
+    ADCSRA = _BV(ADEN) | _BV(ADSC) | _BV(ADIF) | 0x07;
+    DIDR0 = 0;
+    #ifdef DIDR2
+      DIDR2 = 0;
+    #endif
+  }
+
+  // Called by Temperature::init for each sensor at startup
+  static void adc_enable(const uint8_t ch) {
+    #ifdef DIDR2
+      if (ch > 7) { SBI(DIDR2, ch & 0x07); return; }
+    #endif
+    SBI(DIDR0, ch);
+  }
+
+  // Begin ADC sampling on the given channel. Called from Temperature::isr!
+  static void adc_start(const uint8_t ch) {
+    #ifdef MUX5
+      ADCSRB = ch > 7 ? _BV(MUX5) : 0;
+    #else
+      ADCSRB = 0;
+    #endif
+    ADMUX = _BV(REFS0) | (ch & 0x07);
+    SBI(ADCSRA, ADSC);
+  }
+
+  // Is the ADC ready for reading?
+  static bool adc_ready() { return !TEST(ADCSRA, ADSC); }
+
+  // The current value of the ADC register
+  static __typeof__(ADC) adc_value() { return ADC; }
+
+  /**
+   * init_pwm_timers
+   * Set the default frequency for timers 2-5 to 1000HZ
+   */
+  static void init_pwm_timers();
+
+  /**
+   * Set the PWM duty cycle for the pin to the given value.
+   * Optionally invert the duty cycle [default = false]
+   * Optionally change the scale of the provided value to enable finer PWM duty control [default = 255]
+   */
+  static void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size=255, const bool invert=false);
+
+  /**
+   * Set the frequency of the timer for the given pin as close as
+   * possible to the provided desired frequency. Internally calculate
+   * the required waveform generation mode, prescaler, and resolution
+   * values and set timer registers accordingly.
+   * NOTE that the frequency is applied to all pins on the timer (Ex OC3A, OC3B and OC3B)
+   * NOTE that there are limitations, particularly if using TIMER2. (see Configuration_adv.h -> FAST_PWM_FAN Settings)
+   */
+  static void set_pwm_frequency(const pin_t pin, const uint16_t f_desired);
+};
@@ -34,21 +34,21 @@
 #include "../../inc/MarlinConfig.h"

 void spiBegin() {
-  OUT_WRITE(SD_SS_PIN, HIGH);
+  #if PIN_EXISTS(SD_SS)
+    // Do not init HIGH for boards with pin 4 used as Fans or Heaters or otherwise, not likely to have multiple SPI devices anyway.
+    #if defined(__AVR_ATmega644__) || defined(__AVR_ATmega644P__) || defined(__AVR_ATmega644PA__) || defined(__AVR_ATmega1284P__)
+      // SS must be in output mode even it is not chip select
+      SET_OUTPUT(SD_SS_PIN);
+    #else
+      // set SS high - may be chip select for another SPI device
+      OUT_WRITE(SD_SS_PIN, HIGH);
+    #endif
+  #endif
  SET_OUTPUT(SD_SCK_PIN);
  SET_INPUT(SD_MISO_PIN);
  SET_OUTPUT(SD_MOSI_PIN);

-  #if DISABLED(SOFTWARE_SPI)
-    // SS must be in output mode even it is not chip select
-    //SET_OUTPUT(SD_SS_PIN);
-    // set SS high - may be chip select for another SPI device
-    //#if SET_SPI_SS_HIGH
-      //WRITE(SD_SS_PIN, HIGH);
-    //#endif
-    // set a default rate
-    spiInit(1);
-  #endif
+  IF_DISABLED(SOFTWARE_SPI, spiInit(SPI_HALF_SPEED));
 }

 #if NONE(SOFTWARE_SPI, FORCE_SOFT_SPI)
@@ -74,7 +74,8 @@ void spiBegin() {
      #elif defined(PRR0)
        PRR0
      #endif
-        , PRSPI);
+      , PRSPI
+    );

    SPCR = _BV(SPE) | _BV(MSTR) | (spiRate >> 1);
    SPSR = spiRate & 1 || spiRate == 6 ? 0 : _BV(SPI2X);
@@ -21,7 +21,6 @@
 */
 #pragma once

-#define WDT_TIMEOUT   4000000 // 4 second timeout
+#include <SPI.h>

-void watchdog_init();
-void HAL_watchdog_refresh();
+using MarlinSPI = SPIClass;
@@ -486,7 +486,7 @@ void MarlinSerial<Cfg>::write(const uint8_t c) {
    const uint8_t i = (tx_buffer.head + 1) & (Cfg::TX_SIZE - 1);

    // If global interrupts are disabled (as the result of being called from an ISR)...
-    if (!ISRS_ENABLED()) {
+    if (!hal.isr_state()) {

      // Make room by polling if it is possible to transmit, and do so!
      while (i == tx_buffer.tail) {
@@ -534,7 +534,7 @@ void MarlinSerial<Cfg>::flushTX() {
    if (!_written) return;

    // If global interrupts are disabled (as the result of being called from an ISR)...
-    if (!ISRS_ENABLED()) {
+    if (!hal.isr_state()) {

      // Wait until everything was transmitted - We must do polling, as interrupts are disabled
      while (tx_buffer.head != tx_buffer.tail || !B_TXC) {
@@ -191,13 +191,13 @@
                   rx_framing_errors;
    static ring_buffer_pos_t rx_max_enqueued;

-    static FORCE_INLINE ring_buffer_pos_t atomic_read_rx_head();
+    FORCE_INLINE static ring_buffer_pos_t atomic_read_rx_head();

    static volatile bool rx_tail_value_not_stable;
    static volatile uint16_t rx_tail_value_backup;

-    static FORCE_INLINE void atomic_set_rx_tail(ring_buffer_pos_t value);
-    static FORCE_INLINE ring_buffer_pos_t atomic_read_rx_tail();
+    FORCE_INLINE static void atomic_set_rx_tail(ring_buffer_pos_t value);
+    FORCE_INLINE static ring_buffer_pos_t atomic_read_rx_tail();

  public:
    FORCE_INLINE static void store_rxd_char();
@@ -217,7 +217,7 @@
    #endif

    enum { HasEmergencyParser = Cfg::EMERGENCYPARSER };
-    static inline bool emergency_parser_enabled() { return Cfg::EMERGENCYPARSER; }
+    static bool emergency_parser_enabled() { return Cfg::EMERGENCYPARSER; }

    FORCE_INLINE static uint8_t dropped() { return Cfg::DROPPED_RX ? rx_dropped_bytes : 0; }
    FORCE_INLINE static uint8_t buffer_overruns() { return Cfg::RX_OVERRUNS ? rx_buffer_overruns : 0; }
@@ -213,6 +213,51 @@ void setup_endstop_interrupts() {
      pciSetup(K_MIN_PIN);
    #endif
  #endif
+  #if HAS_U_MAX
+    #if (digitalPinToInterrupt(U_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(U_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(U_MAX_PIN), "U_MAX_PIN is not interrupt-capable");
+      pciSetup(U_MAX_PIN);
+    #endif
+  #elif HAS_U_MIN
+    #if (digitalPinToInterrupt(U_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(U_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(U_MIN_PIN), "U_MIN_PIN is not interrupt-capable");
+      pciSetup(U_MIN_PIN);
+    #endif
+  #endif
+  #if HAS_V_MAX
+    #if (digitalPinToInterrupt(V_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(V_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(V_MAX_PIN), "V_MAX_PIN is not interrupt-capable");
+      pciSetup(V_MAX_PIN);
+    #endif
+  #elif HAS_V_MIN
+    #if (digitalPinToInterrupt(V_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(V_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(V_MIN_PIN), "V_MIN_PIN is not interrupt-capable");
+      pciSetup(V_MIN_PIN);
+    #endif
+  #endif
+  #if HAS_W_MAX
+    #if (digitalPinToInterrupt(W_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(W_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(W_MAX_PIN), "W_MAX_PIN is not interrupt-capable");
+      pciSetup(W_MAX_PIN);
+    #endif
+  #elif HAS_W_MIN
+    #if (digitalPinToInterrupt(W_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(W_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(W_MIN_PIN), "W_MIN_PIN is not interrupt-capable");
+      pciSetup(W_MIN_PIN);
+    #endif
+  #endif
  #if HAS_X2_MAX
    #if (digitalPinToInterrupt(X2_MAX_PIN) != NOT_AN_INTERRUPT)
      _ATTACH(X2_MAX_PIN);
@@ -301,5 +346,6 @@ void setup_endstop_interrupts() {
      pciSetup(Z_MIN_PROBE_PIN);
    #endif
  #endif
+
  // If we arrive here without raising an assertion, each pin has either an EXT-interrupt or a PCI.
 }
@@ -21,11 +21,7 @@
 */
 #ifdef __AVR__

-#include "../../inc/MarlinConfigPre.h"
-
-#if NEEDS_HARDWARE_PWM // Specific meta-flag for features that mandate PWM
-
-#include "HAL.h"
+#include "../../inc/MarlinConfig.h"

 struct Timer {
  volatile uint8_t* TCCRnQ[3];  // max 3 TCCR registers per timer
@@ -33,250 +29,194 @@ struct Timer {
  volatile uint16_t* ICRn;      // max 1 ICR register per timer
  uint8_t n;                    // the timer number [0->5]
  uint8_t q;                    // the timer output [0->2] (A->C)
+  bool isPWM;                   // True if pin is a "hardware timer"
+  bool isProtected;             // True if timer is protected
 };

+// Macros for the Timer structure
+#define _SET_WGMnQ(T, V) do{ \
+    *(T.TCCRnQ)[0] = (*(T.TCCRnQ)[0] & ~(0x3 << 0)) | (( int(V)       & 0x3) << 0); \
+    *(T.TCCRnQ)[1] = (*(T.TCCRnQ)[1] & ~(0x3 << 3)) | (((int(V) >> 2) & 0x3) << 3); \
+  }while(0)
+
+// Set TCCR CS bits
+#define _SET_CSn(T, V) (*(T.TCCRnQ)[1] = (*(T.TCCRnQ[1]) & ~(0x7 << 0)) | ((int(V) & 0x7) << 0))
+
+// Set TCCR COM bits
+#define _SET_COMnQ(T, Q, V) (*(T.TCCRnQ)[0] = (*(T.TCCRnQ)[0] & ~(0x3 << (6-2*(Q)))) | (int(V) << (6-2*(Q))))
+
+// Set OCRnQ register
+#define _SET_OCRnQ(T, Q, V) (*(T.OCRnQ)[Q] = int(V) & 0xFFFF)
+
+// Set ICRn register (one per timer)
+#define _SET_ICRn(T, V) (*(T.ICRn) = int(V) & 0xFFFF)
+
 /**
- * get_pwm_timer
- *  Get the timer information and register of the provided pin.
- *  Return a Timer struct containing this information.
- *  Used by set_pwm_frequency, set_pwm_duty
+ * Return a Timer struct describing a pin's timer.
 */
-Timer get_pwm_timer(const pin_t pin) {
+const Timer get_pwm_timer(const pin_t pin) {
+
  uint8_t q = 0;
+
  switch (digitalPinToTimer(pin)) {
-    // Protect reserved timers (TIMER0 & TIMER1)
    #ifdef TCCR0A
-      #if !AVR_AT90USB1286_FAMILY
-        case TIMER0A:
-      #endif
-      case TIMER0B:
+      IF_DISABLED(AVR_AT90USB1286_FAMILY, case TIMER0A:)
    #endif
    #ifdef TCCR1A
      case TIMER1A: case TIMER1B:
    #endif
-                                        break;
-    #if defined(TCCR2) || defined(TCCR2A)
-      #ifdef TCCR2
-        case TIMER2: {
-          Timer timer = {
-            /*TCCRnQ*/  { &TCCR2, nullptr, nullptr },
-            /*OCRnQ*/   { (uint16_t*)&OCR2, nullptr, nullptr },
-            /*ICRn*/      nullptr,
-            /*n, q*/      2, 0
-          };
-        }
-      #elif defined(TCCR2A)
-        #if ENABLED(USE_OCR2A_AS_TOP)
-          case TIMER2A:   break; // protect TIMER2A
-          case TIMER2B: {
-            Timer timer = {
-              /*TCCRnQ*/  { &TCCR2A,  &TCCR2B,  nullptr },
-              /*OCRnQ*/   { (uint16_t*)&OCR2A, (uint16_t*)&OCR2B, nullptr },
-              /*ICRn*/      nullptr,
-              /*n, q*/      2, 1
-            };
-            return timer;
-          }
-        #else
-          case TIMER2B:   ++q;
-          case TIMER2A: {
-            Timer timer = {
-              /*TCCRnQ*/  { &TCCR2A,  &TCCR2B,  nullptr },
-              /*OCRnQ*/   { (uint16_t*)&OCR2A, (uint16_t*)&OCR2B, nullptr },
-              /*ICRn*/      nullptr,
-                            2, q
-            };
-            return timer;
-          }
-        #endif
-      #endif
+
+    break;    // Protect reserved timers (TIMER0 & TIMER1)
+
+    #ifdef TCCR0A
+      case TIMER0B:   // Protected timer, but allow setting the duty cycle on OCR0B for pin D4 only
+        return Timer({ { &TCCR0A, nullptr, nullptr }, { (uint16_t*)&OCR0A, (uint16_t*)&OCR0B, nullptr }, nullptr, 0, 1, true, true });
    #endif
+
+    #if HAS_TCCR2
+      case TIMER2:
+        return Timer({ { &TCCR2, nullptr, nullptr }, { (uint16_t*)&OCR2, nullptr, nullptr }, nullptr, 2, 0, true, false });
+    #elif ENABLED(USE_OCR2A_AS_TOP)
+      case TIMER2A: break; // Protect TIMER2A since its OCR is used by TIMER2B
+      case TIMER2B:
+        return Timer({ { &TCCR2A, &TCCR2B, nullptr }, { (uint16_t*)&OCR2A, (uint16_t*)&OCR2B, nullptr }, nullptr, 2, 1, true, false });
+    #elif defined(TCCR2A)
+      case TIMER2B: ++q; case TIMER2A:
+        return Timer({ { &TCCR2A, &TCCR2B, nullptr }, { (uint16_t*)&OCR2A, (uint16_t*)&OCR2B, nullptr }, nullptr, 2, q, true, false });
+    #endif
+
    #ifdef OCR3C
-      case TIMER3C:   ++q;
-      case TIMER3B:   ++q;
-      case TIMER3A: {
-        Timer timer = {
-          /*TCCRnQ*/  { &TCCR3A,  &TCCR3B,  &TCCR3C },
-          /*OCRnQ*/   { &OCR3A,   &OCR3B,   &OCR3C },
-          /*ICRn*/      &ICR3,
-          /*n, q*/      3, q
-        };
-        return timer;
-      }
+      case TIMER3C: ++q; case TIMER3B: ++q; case TIMER3A:
+        return Timer({ { &TCCR3A, &TCCR3B, &TCCR3C }, { &OCR3A, &OCR3B, &OCR3C  }, &ICR3, 3, q, true, false });
    #elif defined(OCR3B)
-      case TIMER3B:   ++q;
-      case TIMER3A: {
-        Timer timer = {
-          /*TCCRnQ*/  { &TCCR3A,  &TCCR3B,  nullptr },
-          /*OCRnQ*/   { &OCR3A,   &OCR3B,  nullptr },
-          /*ICRn*/      &ICR3,
-          /*n, q*/      3, q
-        };
-        return timer;
-      }
+      case TIMER3B: ++q; case TIMER3A:
+        return Timer({ { &TCCR3A, &TCCR3B, nullptr }, { &OCR3A, &OCR3B, nullptr }, &ICR3, 3, q, true, false });
    #endif
+
    #ifdef TCCR4A
-      case TIMER4C:   ++q;
-      case TIMER4B:   ++q;
-      case TIMER4A: {
-        Timer timer = {
-          /*TCCRnQ*/  { &TCCR4A,  &TCCR4B,  &TCCR4C },
-          /*OCRnQ*/   { &OCR4A,   &OCR4B,   &OCR4C },
-          /*ICRn*/      &ICR4,
-          /*n, q*/      4, q
-        };
-        return timer;
-      }
+      case TIMER4C: ++q; case TIMER4B: ++q; case TIMER4A:
+        return Timer({ { &TCCR4A, &TCCR4B, &TCCR4C }, { &OCR4A, &OCR4B, &OCR4C }, &ICR4, 4, q, true, false });
    #endif
+
    #ifdef TCCR5A
-      case TIMER5C:   ++q;
-      case TIMER5B:   ++q;
-      case TIMER5A: {
-        Timer timer = {
-          /*TCCRnQ*/  { &TCCR5A,  &TCCR5B,  &TCCR5C },
-          /*OCRnQ*/   { &OCR5A,   &OCR5B,   &OCR5C },
-          /*ICRn*/      &ICR5,
-          /*n, q*/      5, q
-        };
-        return timer;
-      }
+      case TIMER5C: ++q; case TIMER5B: ++q; case TIMER5A:
+        return Timer({ { &TCCR5A, &TCCR5B, &TCCR5C }, { &OCR5A, &OCR5B, &OCR5C }, &ICR5, 5, q, true, false });
    #endif
  }
-  Timer timer = {
-      /*TCCRnQ*/  { nullptr, nullptr, nullptr },
-      /*OCRnQ*/   { nullptr, nullptr, nullptr },
-      /*ICRn*/      nullptr,
-                    0, 0
-  };
-  return timer;
+
+  return Timer();
 }

-void set_pwm_frequency(const pin_t pin, int f_desired) {
-  Timer timer = get_pwm_timer(pin);
-  if (timer.n == 0) return; // Don't proceed if protected timer or not recognised
-  uint16_t size;
-  if (timer.n == 2) size = 255; else size = 65535;
+void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
+  const Timer timer = get_pwm_timer(pin);
+  if (timer.isProtected || !timer.isPWM) return; // Don't proceed if protected timer or not recognized

-  uint16_t res = 255;   // resolution (TOP value)
-  uint8_t j = 0;        // prescaler index
-  uint8_t wgm = 1;      // waveform generation mode
+  const bool is_timer2 = timer.n == 2;
+  const uint16_t maxtop = is_timer2 ? 0xFF : 0xFFFF;
+
+  uint16_t res = 0xFF;        // resolution (TOP value)
+  uint8_t j = CS_NONE;        // prescaler index
+  uint8_t wgm = WGM_PWM_PC_8; // waveform generation mode

  // Calculating the prescaler and resolution to use to achieve closest frequency
  if (f_desired != 0) {
-    int f = (F_CPU) / (2 * 1024 * size) + 1; // Initialize frequency as lowest (non-zero) achievable
-    uint16_t prescaler[] = { 0, 1, 8, /*TIMER2 ONLY*/32, 64, /*TIMER2 ONLY*/128, 256, 1024 };
+    constexpr uint16_t prescaler[] = { 1, 8, (32), 64, (128), 256, 1024 };  // (*) are Timer 2 only
+    uint16_t f = (F_CPU) / (2 * 1024 * maxtop) + 1;           // Start with the lowest non-zero frequency achievable (1 or 31)

-    // loop over prescaler values
-    LOOP_S_L_N(i, 1, 8) {
-      uint16_t res_temp_fast = 255, res_temp_phase_correct = 255;
-      if (timer.n == 2) {
-        // No resolution calculation for TIMER2 unless enabled USE_OCR2A_AS_TOP
-        #if ENABLED(USE_OCR2A_AS_TOP)
-          const uint16_t rtf = (F_CPU) / (prescaler[i] * f_desired);
-          res_temp_fast = rtf - 1;
-          res_temp_phase_correct = rtf / 2;
+    LOOP_L_N(i, COUNT(prescaler)) {                           // Loop through all prescaler values
+      const uint16_t p = prescaler[i];
+      uint16_t res_fast_temp, res_pc_temp;
+      if (is_timer2) {
+        #if ENABLED(USE_OCR2A_AS_TOP)                         // No resolution calculation for TIMER2 unless enabled USE_OCR2A_AS_TOP
+          const uint16_t rft = (F_CPU) / (p * f_desired);
+          res_fast_temp = rft - 1;
+          res_pc_temp = rft / 2;
+        #else
+          res_fast_temp = res_pc_temp = maxtop;
        #endif
      }
      else {
-        // Skip TIMER2 specific prescalers when not TIMER2
-        if (i == 3 || i == 5) continue;
-        const uint16_t rtf = (F_CPU) / (prescaler[i] * f_desired);
-        res_temp_fast = rtf - 1;
-        res_temp_phase_correct = rtf / 2;
+        if (p == 32 || p == 128) continue;                    // Skip TIMER2 specific prescalers when not TIMER2
+        const uint16_t rft = (F_CPU) / (p * f_desired);
+        res_fast_temp = rft - 1;
+        res_pc_temp = rft / 2;
      }

-      LIMIT(res_temp_fast, 1U, size);
-      LIMIT(res_temp_phase_correct, 1U, size);
+      LIMIT(res_fast_temp, 1U, maxtop);
+      LIMIT(res_pc_temp, 1U, maxtop);
+
      // Calculate frequencies of test prescaler and resolution values
-      const int f_temp_fast = (F_CPU) / (prescaler[i] * (1 + res_temp_fast)),
-                f_temp_phase_correct = (F_CPU) / (2 * prescaler[i] * res_temp_phase_correct),
-                f_diff = ABS(f - f_desired),
-                f_fast_diff = ABS(f_temp_fast - f_desired),
-                f_phase_diff = ABS(f_temp_phase_correct - f_desired);
+      const uint32_t f_diff      = _MAX(f, f_desired) - _MIN(f, f_desired),
+                     f_fast_temp = (F_CPU) / (p * (1 + res_fast_temp)),
+                     f_fast_diff = _MAX(f_fast_temp, f_desired) - _MIN(f_fast_temp, f_desired),
+                     f_pc_temp   = (F_CPU) / (2 * p * res_pc_temp),
+                     f_pc_diff   = _MAX(f_pc_temp, f_desired) - _MIN(f_pc_temp, f_desired);

-      // If FAST values are closest to desired f
-      if (f_fast_diff < f_diff && f_fast_diff <= f_phase_diff) {
-        // Remember this combination
-        f = f_temp_fast;
-        res = res_temp_fast;
-        j = i;
+      if (f_fast_diff < f_diff && f_fast_diff <= f_pc_diff) { // FAST values are closest to desired f
        // Set the Wave Generation Mode to FAST PWM
-        if (timer.n == 2) {
-          wgm = (
-            #if ENABLED(USE_OCR2A_AS_TOP)
-              WGM2_FAST_PWM_OCR2A
-            #else
-              WGM2_FAST_PWM
-            #endif
-          );
-        }
-        else wgm = WGM_FAST_PWM_ICRn;
+        wgm = is_timer2 ? uint8_t(TERN(USE_OCR2A_AS_TOP, WGM2_FAST_PWM_OCR2A, WGM2_FAST_PWM)) : uint8_t(WGM_FAST_PWM_ICRn);
+        // Remember this combination
+        f = f_fast_temp; res = res_fast_temp; j = i + 1;
      }
-      // If PHASE CORRECT values are closes to desired f
-      else if (f_phase_diff < f_diff) {
-        f = f_temp_phase_correct;
-        res = res_temp_phase_correct;
-        j = i;
+      else if (f_pc_diff < f_diff) {                          // PHASE CORRECT values are closes to desired f
        // Set the Wave Generation Mode to PWM PHASE CORRECT
-        if (timer.n == 2) {
-          wgm = (
-            #if ENABLED(USE_OCR2A_AS_TOP)
-              WGM2_PWM_PC_OCR2A
-            #else
-              WGM2_PWM_PC
-            #endif
-          );
-        }
-        else wgm = WGM_PWM_PC_ICRn;
+        wgm = is_timer2 ? uint8_t(TERN(USE_OCR2A_AS_TOP, WGM2_PWM_PC_OCR2A, WGM2_PWM_PC)) : uint8_t(WGM_PWM_PC_ICRn);
+        f = f_pc_temp; res = res_pc_temp; j = i + 1;
      }
    }
  }
-  _SET_WGMnQ(timer.TCCRnQ, wgm);
-  _SET_CSn(timer.TCCRnQ, j);

-  if (timer.n == 2) {
-    #if ENABLED(USE_OCR2A_AS_TOP)
-      _SET_OCRnQ(timer.OCRnQ, 0, res);  // Set OCR2A value (TOP) = res
-    #endif
+  _SET_WGMnQ(timer, wgm);
+  _SET_CSn(timer, j);
+
+  if (is_timer2) {
+    TERN_(USE_OCR2A_AS_TOP, _SET_OCRnQ(timer, 0, res)); // Set OCR2A value (TOP) = res
  }
  else
-    _SET_ICRn(timer.ICRn, res);         // Set ICRn value (TOP) = res
+    _SET_ICRn(timer, res);                              // Set ICRn value (TOP) = res
 }

-void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=255*/, const bool invert/*=false*/) {
+void MarlinHAL::set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=255*/, const bool invert/*=false*/) {
  // If v is 0 or v_size (max), digitalWrite to LOW or HIGH.
-  // Note that digitalWrite also disables pwm output for us (sets COM bit to 0)
+  // Note that digitalWrite also disables PWM output for us (sets COM bit to 0)
  if (v == 0)
    digitalWrite(pin, invert);
  else if (v == v_size)
    digitalWrite(pin, !invert);
  else {
-    Timer timer = get_pwm_timer(pin);
-    if (timer.n == 0) return; // Don't proceed if protected timer or not recognised
-    // Set compare output mode to CLEAR -> SET or SET -> CLEAR (if inverted)
-    _SET_COMnQ(timer.TCCRnQ, (timer.q
-        #ifdef TCCR2
-          + (timer.q == 2) // COM20 is on bit 4 of TCCR2, thus requires q + 1 in the macro
-        #endif
-      ), COM_CLEAR_SET + invert
-    );
-
-    uint16_t top;
-    if (timer.n == 2) { // if TIMER2
-      top = (
-        #if ENABLED(USE_OCR2A_AS_TOP)
-          *timer.OCRnQ[0] // top = OCR2A
-        #else
-          255 // top = 0xFF (max)
-        #endif
-      );
+    const Timer timer = get_pwm_timer(pin);
+    if (timer.isPWM) {
+      if (timer.n == 0) {
+        _SET_COMnQ(timer, timer.q, COM_CLEAR_SET);  // Only allow a TIMER0B select...
+        _SET_OCRnQ(timer, timer.q, v);              // ...and OCR0B duty update. For output pin D4 no frequency changes are permitted.
+      }
+      else if (!timer.isProtected) {
+        const uint16_t top = timer.n == 2 ? TERN(USE_OCR2A_AS_TOP, *timer.OCRnQ[0], 255) : *timer.ICRn;
+        _SET_COMnQ(timer, SUM_TERN(HAS_TCCR2, timer.q, timer.q == 2), COM_CLEAR_SET + invert);   // COM20 is on bit 4 of TCCR2, so +1 for q==2
+        _SET_OCRnQ(timer, timer.q, uint16_t(uint32_t(v) * top / v_size)); // Scale 8/16-bit v to top value
+      }
    }
    else
-      top = *timer.ICRn; // top = ICRn
-
-    _SET_OCRnQ(timer.OCRnQ, timer.q, v * float(top) / float(v_size)); // Scale 8/16-bit v to top value
+      digitalWrite(pin, v < v_size / 2 ? LOW : HIGH);
  }
 }

-#endif // NEEDS_HARDWARE_PWM
+void MarlinHAL::init_pwm_timers() {
+  // Init some timer frequencies to a default 1KHz
+  const pin_t pwm_pin[] = {
+    #ifdef __AVR_ATmega2560__
+      10, 5, 6, 46
+    #elif defined(__AVR_ATmega1280__)
+      12, 31
+    #elif defined(__AVR_ATmega644__) || defined(__AVR_ATmega1284__)
+      15, 6
+    #elif defined(__AVR_AT90USB1286__) || defined(__AVR_mega64) || defined(__AVR_mega128)
+      16, 24
+    #endif
+  };
+
+  LOOP_L_N(i, COUNT(pwm_pin))
+    set_pwm_frequency(pwm_pin[i], 1000);
+}
+
 #endif // __AVR__
@@ -245,7 +245,7 @@ uint16_t set_pwm_frequency_hz(const_float_t hz, const float dca, const float dcb
  float count = 0;
  if (hz > 0 && (dca || dcb || dcc)) {
    count = float(F_CPU) / hz;            // 1x prescaler, TOP for 16MHz base freq.
-    uint16_t prescaler;                   // Range of 30.5Hz (65535) 64.5KHz (>31)
+    uint16_t prescaler;                   // Range of 30.5Hz (65535) 64.5kHz (>31)

         if (count >= 255. * 256.) { prescaler = 1024; SET_CS(5, PRESCALER_1024); }
    else if (count >= 255. * 64.)  { prescaler = 256;  SET_CS(5,  PRESCALER_256); }
@@ -257,7 +257,7 @@ uint16_t set_pwm_frequency_hz(const_float_t hz, const float dca, const float dcb
    const float pwm_top = round(count);   // Get the rounded count

    ICR5 = (uint16_t)pwm_top - 1;         // Subtract 1 for TOP
-    OCR5A = pwm_top * ABS(dca);          // Update and scale DCs
+    OCR5A = pwm_top * ABS(dca);           // Update and scale DCs
    OCR5B = pwm_top * ABS(dcb);
    OCR5C = pwm_top * ABS(dcc);
    _SET_COM(5, A, dca ? (dca < 0 ? COM_SET_CLEAR : COM_CLEAR_SET) : COM_NORMAL); // Set compare modes
@@ -267,17 +267,17 @@ uint16_t set_pwm_frequency_hz(const_float_t hz, const float dca, const float dcb
    SET_WGM(5, FAST_PWM_ICRn);            // Fast PWM with ICR5 as TOP

    //SERIAL_ECHOLNPGM("Timer 5 Settings:");
-    //SERIAL_ECHOLNPAIR("  Prescaler=", prescaler);
-    //SERIAL_ECHOLNPAIR("        TOP=", ICR5);
-    //SERIAL_ECHOLNPAIR("      OCR5A=", OCR5A);
-    //SERIAL_ECHOLNPAIR("      OCR5B=", OCR5B);
-    //SERIAL_ECHOLNPAIR("      OCR5C=", OCR5C);
+    //SERIAL_ECHOLNPGM("  Prescaler=", prescaler);
+    //SERIAL_ECHOLNPGM("        TOP=", ICR5);
+    //SERIAL_ECHOLNPGM("      OCR5A=", OCR5A);
+    //SERIAL_ECHOLNPGM("      OCR5B=", OCR5B);
+    //SERIAL_ECHOLNPGM("      OCR5C=", OCR5C);
  }
  else {
    // Restore the default for Timer 5
    SET_WGM(5, PWM_PC_8);                 // PWM 8-bit (Phase Correct)
    SET_COMS(5, NORMAL, NORMAL, NORMAL);  // Do nothing
-    SET_CS(5, PRESCALER_64);              // 16MHz / 64 = 250KHz
+    SET_CS(5, PRESCALER_64);              // 16MHz / 64 = 250kHz
    OCR5A = OCR5B = OCR5C = 0;
  }
  return round(count);
@@ -118,7 +118,7 @@
 */

 // Waveform Generation Modes
-enum WaveGenMode : char {
+enum WaveGenMode : uint8_t {
  WGM_NORMAL,          //  0
  WGM_PWM_PC_8,        //  1
  WGM_PWM_PC_9,        //  2
@@ -138,19 +138,19 @@ enum WaveGenMode : char {
 };

 // Wavefore Generation Modes (Timer 2 only)
-enum WaveGenMode2 : char {
-  WGM2_NORMAL,          // 0
-  WGM2_PWM_PC,          // 1
-  WGM2_CTC_OCR2A,       // 2
-  WGM2_FAST_PWM,        // 3
-  WGM2_reserved_1,      // 4
-  WGM2_PWM_PC_OCR2A,    // 5
-  WGM2_reserved_2,      // 6
-  WGM2_FAST_PWM_OCR2A,  // 7
+enum WaveGenMode2 : uint8_t {
+  WGM2_NORMAL,         // 0
+  WGM2_PWM_PC,         // 1
+  WGM2_CTC_OCR2A,      // 2
+  WGM2_FAST_PWM,       // 3
+  WGM2_reserved_1,     // 4
+  WGM2_PWM_PC_OCR2A,   // 5
+  WGM2_reserved_2,     // 6
+  WGM2_FAST_PWM_OCR2A, // 7
 };

 // Compare Modes
-enum CompareMode : char {
+enum CompareMode : uint8_t {
  COM_NORMAL,          //  0
  COM_TOGGLE,          //  1  Non-PWM: OCnx ... Both PWM (WGM 9,11,14,15): OCnA only ... else NORMAL
  COM_CLEAR_SET,       //  2  Non-PWM: OCnx ... Fast PWM: OCnx/Bottom ... PF-FC: OCnx Up/Down
@@ -158,7 +158,7 @@ enum CompareMode : char {
 };

 // Clock Sources
-enum ClockSource : char {
+enum ClockSource : uint8_t {
  CS_NONE,             //  0
  CS_PRESCALER_1,      //  1
  CS_PRESCALER_8,      //  2
@@ -170,7 +170,7 @@ enum ClockSource : char {
 };

 // Clock Sources (Timer 2 only)
-enum ClockSource2 : char {
+enum ClockSource2 : uint8_t {
  CS2_NONE,            //  0
  CS2_PRESCALER_1,     //  1
  CS2_PRESCALER_8,     //  2
@@ -203,40 +203,33 @@ enum ClockSource2 : char {
    TCCR##T##B = (TCCR##T##B & ~(0x3 << WGM##T##2)) | (((int(V) >> 2) & 0x3) << WGM##T##2); \
  }while(0)
 #define SET_WGM(T,V) _SET_WGM(T,WGM_##V)
-// Runtime (see set_pwm_frequency):
-#define _SET_WGMnQ(TCCRnQ, V) do{ \
-    *(TCCRnQ)[0] = (*(TCCRnQ)[0] & ~(0x3 << 0)) | (( int(V)       & 0x3) << 0); \
-    *(TCCRnQ)[1] = (*(TCCRnQ)[1] & ~(0x3 << 3)) | (((int(V) >> 2) & 0x3) << 3); \
-  }while(0)

 // Set Clock Select bits
 // Ex: SET_CS3(PRESCALER_64);
+#ifdef TCCR2
+  #define HAS_TCCR2 1
+#endif
 #define _SET_CS(T,V) (TCCR##T##B = (TCCR##T##B & ~(0x7 << CS##T##0)) | ((int(V) & 0x7) << CS##T##0))
 #define _SET_CS0(V) _SET_CS(0,V)
 #define _SET_CS1(V) _SET_CS(1,V)
-#ifdef TCCR2
-  #define _SET_CS2(V) (TCCR2 = (TCCR2 & ~(0x7 << CS20)) | (int(V) << CS20))
-#else
-  #define _SET_CS2(V) _SET_CS(2,V)
-#endif
 #define _SET_CS3(V) _SET_CS(3,V)
 #define _SET_CS4(V) _SET_CS(4,V)
 #define _SET_CS5(V) _SET_CS(5,V)
 #define SET_CS0(V) _SET_CS0(CS_##V)
 #define SET_CS1(V) _SET_CS1(CS_##V)
-#ifdef TCCR2
+
+#if HAS_TCCR2
+  #define _SET_CS2(V) (TCCR2 = (TCCR2 & ~(0x7 << CS20)) | (int(V) << CS20))
  #define SET_CS2(V) _SET_CS2(CS2_##V)
 #else
+  #define _SET_CS2(V) _SET_CS(2,V)
  #define SET_CS2(V) _SET_CS2(CS_##V)
 #endif
+
 #define SET_CS3(V) _SET_CS3(CS_##V)
 #define SET_CS4(V) _SET_CS4(CS_##V)
 #define SET_CS5(V) _SET_CS5(CS_##V)
 #define SET_CS(T,V) SET_CS##T(V)
-// Runtime (see set_pwm_frequency)
-#define _SET_CSn(TCCRnQ, V) do{ \
-    (*(TCCRnQ)[1] = (*(TCCRnQ[1]) & ~(0x7 << 0)) | ((int(V) & 0x7) << 0)); \
-  }while(0)

 // Set Compare Mode bits
 // Ex: SET_COMS(4,CLEAR_SET,CLEAR_SET,CLEAR_SET);
@@ -246,22 +239,6 @@ enum ClockSource2 : char {
 #define SET_COMB(T,V) SET_COM(T,B,V)
 #define SET_COMC(T,V) SET_COM(T,C,V)
 #define SET_COMS(T,V1,V2,V3) do{ SET_COMA(T,V1); SET_COMB(T,V2); SET_COMC(T,V3); }while(0)
-// Runtime (see set_pwm_duty)
-#define _SET_COMnQ(TCCRnQ, Q, V) do{ \
-    (*(TCCRnQ)[0] = (*(TCCRnQ)[0] & ~(0x3 << (6-2*(Q)))) | (int(V) << (6-2*(Q)))); \
-  }while(0)
-
-// Set OCRnQ register
-// Runtime (see set_pwm_duty):
-#define _SET_OCRnQ(OCRnQ, Q, V) do{ \
-    (*(OCRnQ)[(Q)] = (0x0000) | (int(V) & 0xFFFF)); \
-  }while(0)
-
-// Set ICRn register (one per timer)
-// Runtime (see set_pwm_frequency)
-#define _SET_ICRn(ICRn, V) do{ \
-    (*(ICRn) = (0x0000) | (int(V) & 0xFFFF)); \
-  }while(0)

 // Set Noise Canceler bit
 // Ex: SET_ICNC(2,1)
@@ -25,25 +25,57 @@
 * Test AVR-specific configuration values for errors at compile-time.
 */

+/**
+ * Check for common serial pin conflicts
+ */
+#define CHECK_SERIAL_PIN(N) ( \
+     X_STOP_PIN == N || Y_STOP_PIN == N || Z_STOP_PIN == N \
+  || X_MIN_PIN  == N || Y_MIN_PIN  == N || Z_MIN_PIN  == N \
+  || X_MAX_PIN  == N || Y_MAX_PIN  == N || Z_MAX_PIN  == N \
+  || X_STEP_PIN == N || Y_STEP_PIN == N || Z_STEP_PIN == N \
+  || X_DIR_PIN  == N || Y_DIR_PIN  == N || Z_DIR_PIN  == N \
+  || X_ENA_PIN  == N || Y_ENA_PIN  == N || Z_ENA_PIN  == N \
+)
+#if CONF_SERIAL_IS(0) // D0-D1. No known conflicts.
+#endif
+#if CONF_SERIAL_IS(1) && (CHECK_SERIAL_PIN(18) || CHECK_SERIAL_PIN(19))
+  #error "Serial Port 1 pin D18 and/or D19 conflicts with another pin on the board."
+#endif
+#if CONF_SERIAL_IS(2) && (CHECK_SERIAL_PIN(16) || CHECK_SERIAL_PIN(17))
+  #error "Serial Port 2 pin D16 and/or D17 conflicts with another pin on the board."
+#endif
+#if CONF_SERIAL_IS(3) && (CHECK_SERIAL_PIN(14) || CHECK_SERIAL_PIN(15))
+  #error "Serial Port 3 pin D14 and/or D15 conflicts with another pin on the board."
+#endif
+#undef CHECK_SERIAL_PIN
+
 /**
 * Checks for FAST PWM
 */
-#if ENABLED(FAST_PWM_FAN) && (ENABLED(USE_OCR2A_AS_TOP) && defined(TCCR2))
-  #error "USE_OCR2A_AS_TOP does not apply to devices with a single output TIMER2"
+#if ALL(FAST_PWM_FAN, USE_OCR2A_AS_TOP, HAS_TCCR2)
+  #error "USE_OCR2A_AS_TOP does not apply to devices with a single output TIMER2."
+#endif
+
+/**
+ * Checks for SOFT PWM
+ */
+#if HAS_FAN0 && FAN_PIN == 9 && DISABLED(FAN_SOFT_PWM) && ENABLED(SPEAKER)
+  #error "FAN_PIN 9 Hardware PWM uses Timer 2 which conflicts with Arduino AVR Tone Timer (for SPEAKER)."
+  #error "Disable SPEAKER or enable FAN_SOFT_PWM."
 #endif

 /**
 * Sanity checks for Spindle / Laser PWM
 */
-#if ENABLED(SPINDLE_LASER_PWM)
+#if ENABLED(SPINDLE_LASER_USE_PWM)
  #include "../ServoTimers.h"   // Needed to check timer availability (_useTimer3)
  #if SPINDLE_LASER_PWM_PIN == 4 || WITHIN(SPINDLE_LASER_PWM_PIN, 11, 13)
    #error "Counter/Timer for SPINDLE_LASER_PWM_PIN is used by a system interrupt."
  #elif NUM_SERVOS > 0 && defined(_useTimer3) && (WITHIN(SPINDLE_LASER_PWM_PIN, 2, 3) || SPINDLE_LASER_PWM_PIN == 5)
    #error "Counter/Timer for SPINDLE_LASER_PWM_PIN is used by the servo system."
  #endif
-#elif defined(SPINDLE_LASER_FREQUENCY)
-  #error "SPINDLE_LASER_FREQUENCY requires SPINDLE_LASER_PWM."
+#elif SPINDLE_LASER_FREQUENCY
+  #error "SPINDLE_LASER_FREQUENCY requires SPINDLE_LASER_USE_PWM."
 #endif

 /**
@@ -63,3 +95,7 @@
 #if ENABLED(POSTMORTEM_DEBUGGING)
  #error "POSTMORTEM_DEBUGGING is not supported on AVR boards."
 #endif
+
+#if USING_PULLDOWNS
+  #error "PULLDOWN pin mode is not available on AVR boards."
+#endif
@@ -35,7 +35,7 @@
 // C B A is longIn1
 // D C B A is longIn2
 //
-static FORCE_INLINE uint16_t MultiU24X32toH16(uint32_t longIn1, uint32_t longIn2) {
+FORCE_INLINE static uint16_t MultiU24X32toH16(uint32_t longIn1, uint32_t longIn2) {
  uint8_t tmp1;
  uint8_t tmp2;
  uint16_t intRes;
@@ -89,7 +89,7 @@ static FORCE_INLINE uint16_t MultiU24X32toH16(uint32_t longIn1, uint32_t longIn2
 // uses:
 // r26 to store 0
 // r27 to store the byte 1 of the 24 bit result
-static FORCE_INLINE uint16_t MultiU16X8toH16(uint8_t charIn1, uint16_t intIn2) {
+FORCE_INLINE static uint16_t MultiU16X8toH16(uint8_t charIn1, uint16_t intIn2) {
  uint8_t tmp;
  uint16_t intRes;
  __asm__ __volatile__ (
@@ -2,6 +2,9 @@
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
@@ -71,7 +74,7 @@
 #define MULTI_NAME_PAD 26 // space needed to be pretty if not first name assigned to a pin

 void PRINT_ARRAY_NAME(uint8_t x) {
-  char *name_mem_pointer = (char*)pgm_read_ptr(&pin_array[x].name);
+  const char * const name_mem_pointer = (PGM_P)pgm_read_ptr(&pin_array[x].name);
  LOOP_L_N(y, MAX_NAME_LENGTH) {
    char temp_char = pgm_read_byte(name_mem_pointer + y);
    if (temp_char != 0)
@@ -99,7 +102,7 @@ void PRINT_ARRAY_NAME(uint8_t x) {
      return true;                                              \
    } else return false

-
+#define ABTEST(N) defined(TCCR##N##A) && defined(COM##N##A1)

 /**
 * Print a pin's PWM status.
@@ -110,7 +113,7 @@ static bool pwm_status(uint8_t pin) {

  switch (digitalPinToTimer_DEBUG(pin)) {

-    #if defined(TCCR0A) && defined(COM0A1)
+    #if ABTEST(0)
      #ifdef TIMER0A
        #if !AVR_AT90USB1286_FAMILY  // not available in Teensyduino type IDEs
          PWM_CASE(0, A);
@@ -119,20 +122,20 @@ static bool pwm_status(uint8_t pin) {
      PWM_CASE(0, B);
    #endif

-    #if defined(TCCR1A) && defined(COM1A1)
+    #if ABTEST(1)
      PWM_CASE(1, A);
      PWM_CASE(1, B);
-     #if defined(COM1C1) && defined(TIMER1C)
-      PWM_CASE(1, C);
-     #endif
+      #if defined(COM1C1) && defined(TIMER1C)
+        PWM_CASE(1, C);
+      #endif
    #endif

-    #if defined(TCCR2A) && defined(COM2A1)
+    #if ABTEST(2)
      PWM_CASE(2, A);
      PWM_CASE(2, B);
    #endif

-    #if defined(TCCR3A) && defined(COM3A1)
+    #if ABTEST(3)
      PWM_CASE(3, A);
      PWM_CASE(3, B);
      #ifdef COM3C1
@@ -146,7 +149,7 @@ static bool pwm_status(uint8_t pin) {
      PWM_CASE(4, C);
    #endif

-    #if defined(TCCR5A) && defined(COM5A1)
+    #if ABTEST(5)
      PWM_CASE(5, A);
      PWM_CASE(5, B);
      PWM_CASE(5, C);
@@ -163,16 +166,16 @@ static bool pwm_status(uint8_t pin) {
 const volatile uint8_t* const PWM_other[][3] PROGMEM = {
    { &TCCR0A, &TCCR0B, &TIMSK0 },
    { &TCCR1A, &TCCR1B, &TIMSK1 },
-  #if defined(TCCR2A) && defined(COM2A1)
+  #if ABTEST(2)
    { &TCCR2A, &TCCR2B, &TIMSK2 },
  #endif
-  #if defined(TCCR3A) && defined(COM3A1)
+  #if ABTEST(3)
    { &TCCR3A, &TCCR3B, &TIMSK3 },
  #endif
  #ifdef TCCR4A
    { &TCCR4A, &TCCR4B, &TIMSK4 },
  #endif
-  #if defined(TCCR5A) && defined(COM5A1)
+  #if ABTEST(5)
    { &TCCR5A, &TCCR5B, &TIMSK5 },
  #endif
 };
@@ -192,11 +195,11 @@ const volatile uint8_t* const PWM_OCR[][3] PROGMEM = {
   { (const uint8_t*)&OCR1A, (const uint8_t*)&OCR1B, 0 },
  #endif

-  #if defined(TCCR2A) && defined(COM2A1)
+  #if ABTEST(2)
    { &OCR2A, &OCR2B, 0 },
  #endif

-  #if defined(TCCR3A) && defined(COM3A1)
+  #if ABTEST(3)
    #ifdef COM3C1
      { (const uint8_t*)&OCR3A, (const uint8_t*)&OCR3B, (const uint8_t*)&OCR3C },
    #else
@@ -208,7 +211,7 @@ const volatile uint8_t* const PWM_OCR[][3] PROGMEM = {
    { (const uint8_t*)&OCR4A, (const uint8_t*)&OCR4B, (const uint8_t*)&OCR4C },
  #endif

-  #if defined(TCCR5A) && defined(COM5A1)
+  #if ABTEST(5)
    { (const uint8_t*)&OCR5A, (const uint8_t*)&OCR5B, (const uint8_t*)&OCR5C },
  #endif
 };
@@ -235,9 +238,9 @@ static void print_is_also_tied() { SERIAL_ECHOPGM(" is also tied to this pin");

 inline void com_print(const uint8_t N, const uint8_t Z) {
  const uint8_t *TCCRA = (uint8_t*)TCCR_A(N);
-  SERIAL_ECHOPAIR("    COM", AS_CHAR('0' + N));
+  SERIAL_ECHOPGM("    COM", AS_DIGIT(N));
  SERIAL_CHAR(Z);
-  SERIAL_ECHOPAIR(": ", int((*TCCRA >> (6 - Z * 2)) & 0x03));
+  SERIAL_ECHOPGM(": ", int((*TCCRA >> (6 - Z * 2)) & 0x03));
 }

 void timer_prefix(uint8_t T, char L, uint8_t N) {  // T - timer    L - pwm  N - WGM bit layout
@@ -247,7 +250,7 @@ void timer_prefix(uint8_t T, char L, uint8_t N) {  // T - timer    L - pwm  N -
  uint8_t WGM = (((*TCCRB & _BV(WGM_2)) >> 1) | (*TCCRA & (_BV(WGM_0) | _BV(WGM_1))));
  if (N == 4) WGM |= ((*TCCRB & _BV(WGM_3)) >> 1);

-  SERIAL_ECHOPAIR("    TIMER", AS_CHAR(T + '0'));
+  SERIAL_ECHOPGM("    TIMER", AS_DIGIT(T));
  SERIAL_CHAR(L);
  SERIAL_ECHO_SP(3);

@@ -259,14 +262,14 @@ void timer_prefix(uint8_t T, char L, uint8_t N) {  // T - timer    L - pwm  N -
    const uint16_t *OCRVAL16 = (uint16_t*)OCR_VAL(T, L - 'A');
    PWM_PRINT(*OCRVAL16);
  }
-  SERIAL_ECHOPAIR("    WGM: ", WGM);
+  SERIAL_ECHOPGM("    WGM: ", WGM);
  com_print(T,L);
-  SERIAL_ECHOPAIR("    CS: ", (*TCCRB & (_BV(CS_0) | _BV(CS_1) | _BV(CS_2)) ));
-  SERIAL_ECHOPAIR("    TCCR", AS_CHAR(T + '0'), "A: ", *TCCRA);
-  SERIAL_ECHOPAIR("    TCCR", AS_CHAR(T + '0'), "B: ", *TCCRB);
+  SERIAL_ECHOPGM("    CS: ", (*TCCRB & (_BV(CS_0) | _BV(CS_1) | _BV(CS_2)) ));
+  SERIAL_ECHOPGM("    TCCR", AS_DIGIT(T), "A: ", *TCCRA);
+  SERIAL_ECHOPGM("    TCCR", AS_DIGIT(T), "B: ", *TCCRB);

  const uint8_t *TMSK = (uint8_t*)TIMSK(T);
-  SERIAL_ECHOPAIR("    TIMSK", AS_CHAR(T + '0'), ": ", *TMSK);
+  SERIAL_ECHOPGM("    TIMSK", AS_DIGIT(T), ": ", *TMSK);

  const uint8_t OCIE = L - 'A' + 1;
  if (N == 3) { if (WGM == 0 || WGM == 2 || WGM ==  4 || WGM ==  6) err_is_counter(); }
@@ -278,7 +281,7 @@ void timer_prefix(uint8_t T, char L, uint8_t N) {  // T - timer    L - pwm  N -
 static void pwm_details(uint8_t pin) {
  switch (digitalPinToTimer_DEBUG(pin)) {

-    #if defined(TCCR0A) && defined(COM0A1)
+    #if ABTEST(0)
      #ifdef TIMER0A
        #if !AVR_AT90USB1286_FAMILY  // not available in Teensyduino type IDEs
          case TIMER0A: timer_prefix(0, 'A', 3); break;
@@ -287,7 +290,7 @@ static void pwm_details(uint8_t pin) {
      case TIMER0B: timer_prefix(0, 'B', 3); break;
    #endif

-    #if defined(TCCR1A) && defined(COM1A1)
+    #if ABTEST(1)
      case TIMER1A: timer_prefix(1, 'A', 4); break;
      case TIMER1B: timer_prefix(1, 'B', 4); break;
      #if defined(COM1C1) && defined(TIMER1C)
@@ -295,12 +298,12 @@ static void pwm_details(uint8_t pin) {
      #endif
    #endif

-    #if defined(TCCR2A) && defined(COM2A1)
+    #if ABTEST(2)
      case TIMER2A: timer_prefix(2, 'A', 3); break;
      case TIMER2B: timer_prefix(2, 'B', 3); break;
    #endif

-    #if defined(TCCR3A) && defined(COM3A1)
+    #if ABTEST(3)
      case TIMER3A: timer_prefix(3, 'A', 4); break;
      case TIMER3B: timer_prefix(3, 'B', 4); break;
      #ifdef COM3C1
@@ -314,7 +317,7 @@ static void pwm_details(uint8_t pin) {
      case TIMER4C: timer_prefix(4, 'C', 4); break;
    #endif

-    #if defined(TCCR5A) && defined(COM5A1)
+    #if ABTEST(5)
      case TIMER5A: timer_prefix(5, 'A', 4); break;
      case TIMER5B: timer_prefix(5, 'B', 4); break;
      case TIMER5C: timer_prefix(5, 'C', 4); break;
@@ -348,7 +351,6 @@ static void pwm_details(uint8_t pin) {
  #endif
 } // pwm_details

-
 #ifndef digitalRead_mod                   // Use Teensyduino's version of digitalRead - it doesn't disable the PWMs
  int digitalRead_mod(const int8_t pin) { // same as digitalRead except the PWM stop section has been removed
    const uint8_t port = digitalPinToPort_DEBUG(pin);
@@ -393,3 +395,6 @@ static void pwm_details(uint8_t pin) {
 #endif

 #define PRINT_PIN(p) do{ sprintf_P(buffer, PSTR("%3d "), p); SERIAL_ECHO(buffer); }while(0)
+#define PRINT_PIN_ANALOG(p) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), DIGITAL_PIN_TO_ANALOG_PIN(pin)); SERIAL_ECHO(buffer); }while(0)
+
+#undef ABTEST
@@ -2,6 +2,9 @@
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
@@ -2,6 +2,9 @@
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
@@ -34,14 +34,14 @@ typedef uint16_t hal_timer_t;

 #define HAL_TIMER_RATE          ((F_CPU) / 8)    // i.e., 2MHz or 2.5MHz

-#ifndef STEP_TIMER_NUM
-  #define STEP_TIMER_NUM        1
+#ifndef MF_TIMER_STEP
+  #define MF_TIMER_STEP         1
 #endif
-#ifndef PULSE_TIMER_NUM
-  #define PULSE_TIMER_NUM       STEP_TIMER_NUM
+#ifndef MF_TIMER_PULSE
+  #define MF_TIMER_PULSE        MF_TIMER_STEP
 #endif
-#ifndef TEMP_TIMER_NUM
-  #define TEMP_TIMER_NUM        0
+#ifndef MF_TIMER_TEMP
+  #define MF_TIMER_TEMP         0
 #endif

 #define TEMP_TIMER_FREQUENCY    ((F_CPU) / 64.0 / 256.0)
@@ -58,13 +58,13 @@ typedef uint16_t hal_timer_t;
 #define DISABLE_STEPPER_DRIVER_INTERRUPT() CBI(TIMSK1, OCIE1A)
 #define STEPPER_ISR_ENABLED()             TEST(TIMSK1, OCIE1A)

-#define ENABLE_TEMPERATURE_INTERRUPT()     SBI(TIMSK0, OCIE0B)
-#define DISABLE_TEMPERATURE_INTERRUPT()    CBI(TIMSK0, OCIE0B)
-#define TEMPERATURE_ISR_ENABLED()         TEST(TIMSK0, OCIE0B)
+#define ENABLE_TEMPERATURE_INTERRUPT()     SBI(TIMSK0, OCIE0A)
+#define DISABLE_TEMPERATURE_INTERRUPT()    CBI(TIMSK0, OCIE0A)
+#define TEMPERATURE_ISR_ENABLED()         TEST(TIMSK0, OCIE0A)

 FORCE_INLINE void HAL_timer_start(const uint8_t timer_num, const uint32_t) {
  switch (timer_num) {
-    case STEP_TIMER_NUM:
+    case MF_TIMER_STEP:
      // waveform generation = 0100 = CTC
      SET_WGM(1, CTC_OCRnA);

@@ -84,10 +84,10 @@ FORCE_INLINE void HAL_timer_start(const uint8_t timer_num, const uint32_t) {
      TCNT1 = 0;
      break;

-    case TEMP_TIMER_NUM:
+    case MF_TIMER_TEMP:
      // Use timer0 for temperature measurement
      // Interleave temperature interrupt with millies interrupt
-      OCR0B = 128;
+      OCR0A = 128;
      break;
  }
 }
@@ -109,12 +109,12 @@ FORCE_INLINE void HAL_timer_start(const uint8_t timer_num, const uint32_t) {
 * (otherwise, characters will be lost due to UART overflow).
 * Then: Stepper, Endstops, Temperature, and -finally- all others.
 */
-#define HAL_timer_isr_prologue(TIMER_NUM)
-#define HAL_timer_isr_epilogue(TIMER_NUM)
+#define HAL_timer_isr_prologue(T) NOOP
+#define HAL_timer_isr_epilogue(T) NOOP

-/* 18 cycles maximum latency */
 #ifndef HAL_STEP_TIMER_ISR

+/* 18 cycles maximum latency */
 #define HAL_STEP_TIMER_ISR() \
 extern "C" void TIMER1_COMPA_vect() __attribute__ ((signal, naked, used, externally_visible)); \
 extern "C" void TIMER1_COMPA_vect_bottom() asm ("TIMER1_COMPA_vect_bottom") __attribute__ ((used, externally_visible, noinline)); \
@@ -180,7 +180,7 @@ void TIMER1_COMPA_vect() { \
    :                                   \
    : [timsk0] "i" ((uint16_t)&TIMSK0), \
      [timsk1] "i" ((uint16_t)&TIMSK1), \
-      [msk0] "M" ((uint8_t)(1<<OCIE0B)),\
+      [msk0] "M" ((uint8_t)(1<<OCIE0A)),\
      [msk1] "M" ((uint8_t)(1<<OCIE1A)) \
    : \
  ); \
@@ -193,9 +193,9 @@ void TIMER1_COMPA_vect_bottom()

 /* 14 cycles maximum latency */
 #define HAL_TEMP_TIMER_ISR() \
-extern "C" void TIMER0_COMPB_vect() __attribute__ ((signal, naked, used, externally_visible)); \
-extern "C" void TIMER0_COMPB_vect_bottom()  asm ("TIMER0_COMPB_vect_bottom") __attribute__ ((used, externally_visible, noinline)); \
-void TIMER0_COMPB_vect() { \
+extern "C" void TIMER0_COMPA_vect() __attribute__ ((signal, naked, used, externally_visible)); \
+extern "C" void TIMER0_COMPA_vect_bottom()  asm ("TIMER0_COMPA_vect_bottom") __attribute__ ((used, externally_visible, noinline)); \
+void TIMER0_COMPA_vect() { \
  __asm__ __volatile__ ( \
    A("push r16")                       /* 2 Save R16 */ \
    A("in r16, __SREG__")               /* 1 Get SREG */ \
@@ -223,7 +223,7 @@ void TIMER0_COMPB_vect() { \
    A("push r30")                       \
    A("push r31")                       \
    A("clr r1")                         /* C runtime expects this register to be 0 */ \
-    A("call TIMER0_COMPB_vect_bottom")  /* Call the bottom handler - No inlining allowed, otherwise registers used are not saved */   \
+    A("call TIMER0_COMPA_vect_bottom")  /* Call the bottom handler - No inlining allowed, otherwise registers used are not saved */   \
    A("pop r31")                        \
    A("pop r30")                        \
    A("pop r27")                        \
@@ -251,10 +251,10 @@ void TIMER0_COMPB_vect() { \
    A("reti")                           /* 4 Return from interrupt */ \
    :                                   \
    : [timsk0] "i"((uint16_t)&TIMSK0),  \
-      [msk0] "M" ((uint8_t)(1<<OCIE0B)) \
+      [msk0] "M" ((uint8_t)(1<<OCIE0A)) \
    : \
  ); \
 } \
-void TIMER0_COMPB_vect_bottom()
+void TIMER0_COMPA_vect_bottom()

 #endif // HAL_TEMP_TIMER_ISR
@@ -64,8 +64,8 @@

 #include <U8glib-HAL.h>

-uint8_t u8g_bitData, u8g_bitNotData, u8g_bitClock, u8g_bitNotClock;
-volatile uint8_t *u8g_outData, *u8g_outClock;
+static uint8_t u8g_bitData, u8g_bitNotData, u8g_bitClock, u8g_bitNotClock;
+static volatile uint8_t *u8g_outData, *u8g_outClock;

 static void u8g_com_arduino_init_shift_out(uint8_t dataPin, uint8_t clockPin) {
  u8g_outData = portOutputRegister(digitalPinToPort(dataPin));
@@ -1,70 +0,0 @@
-/**
- * Marlin 3D Printer Firmware
- * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
- *
- * Based on Sprinter and grbl.
- * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- *
- */
-#ifdef __AVR__
-
-#include "../../inc/MarlinConfig.h"
-
-#if ENABLED(USE_WATCHDOG)
-
-#include "watchdog.h"
-
-#include "../../MarlinCore.h"
-
-// Initialize watchdog with 8s timeout, if possible. Otherwise, make it 4s.
-void watchdog_init() {
-  #if ENABLED(WATCHDOG_DURATION_8S) && defined(WDTO_8S)
-    #define WDTO_NS WDTO_8S
-  #else
-    #define WDTO_NS WDTO_4S
-  #endif
-  #if ENABLED(WATCHDOG_RESET_MANUAL)
-    // Enable the watchdog timer, but only for the interrupt.
-    // Take care, as this requires the correct order of operation, with interrupts disabled.
-    // See the datasheet of any AVR chip for details.
-    wdt_reset();
-    cli();
-    _WD_CONTROL_REG = _BV(_WD_CHANGE_BIT) | _BV(WDE);
-    _WD_CONTROL_REG = _BV(WDIE) | (WDTO_NS & 0x07) | ((WDTO_NS & 0x08) << 2); // WDTO_NS directly does not work. bit 0-2 are consecutive in the register but the highest value bit is at bit 5
-                                                                              // So worked for up to WDTO_2S
-    sei();
-    wdt_reset();
-  #else
-    wdt_enable(WDTO_NS); // The function handles the upper bit correct.
-  #endif
-  //delay(10000); // test it!
-}
-
-//===========================================================================
-//=================================== ISR ===================================
-//===========================================================================
-
-// Watchdog timer interrupt, called if main program blocks >4sec and manual reset is enabled.
-#if ENABLED(WATCHDOG_RESET_MANUAL)
-  ISR(WDT_vect) {
-    sei();  // With the interrupt driven serial we need to allow interrupts.
-    SERIAL_ERROR_MSG(STR_WATCHDOG_FIRED);
-    minkill();  // interrupt-safe final kill and infinite loop
-  }
-#endif
-
-#endif // USE_WATCHDOG
-#endif // __AVR__
@@ -25,7 +25,7 @@
 #ifdef ARDUINO_ARCH_SAM

 #include "../../inc/MarlinConfig.h"
-#include "HAL.h"
+#include "../../MarlinCore.h"

 #include <Wire.h>
 #include "usb/usb_task.h"
@@ -34,39 +34,33 @@
 // Public Variables
 // ------------------------

-uint16_t HAL_adc_result;
+uint16_t MarlinHAL::adc_result;

 // ------------------------
 // Public functions
 // ------------------------

-TERN_(POSTMORTEM_DEBUGGING, extern void install_min_serial());
+#if ENABLED(POSTMORTEM_DEBUGGING)
+  extern void install_min_serial();
+#endif

-// HAL initialization task
-void HAL_init() {
-  // Initialize the USB stack
+void MarlinHAL::init() {
  #if ENABLED(SDSUPPORT)
    OUT_WRITE(SDSS, HIGH);  // Try to set SDSS inactive before any other SPI users start up
  #endif
-  usb_task_init();
+  usb_task_init();          // Initialize the USB stack
  TERN_(POSTMORTEM_DEBUGGING, install_min_serial()); // Install the min serial handler
 }

-// HAL idle task
-void HAL_idletask() {
-  // Perform USB stack housekeeping
-  usb_task_idle();
+void MarlinHAL::init_board() {
+  #ifdef BOARD_INIT
+    BOARD_INIT();
+  #endif
 }

-// Disable interrupts
-void cli() { noInterrupts(); }
+void MarlinHAL::idletask() { usb_task_idle(); } // Perform USB stack housekeeping

-// Enable interrupts
-void sei() { interrupts(); }
-
-void HAL_clear_reset_source() { }
-
-uint8_t HAL_get_reset_source() {
+uint8_t MarlinHAL::get_reset_source() {
  switch ((RSTC->RSTC_SR >> 8) & 0x07) {
    case 0: return RST_POWER_ON;
    case 1: return RST_BACKUP;
@@ -77,13 +71,105 @@ uint8_t HAL_get_reset_source() {
  }
 }

-void HAL_reboot() { rstc_start_software_reset(RSTC); }
+void MarlinHAL::reboot() { rstc_start_software_reset(RSTC); }

-void _delay_ms(const int delay_ms) {
-  // Todo: port for Due?
-  delay(delay_ms);
+// ------------------------
+// Watchdog Timer
+// ------------------------
+
+#if ENABLED(USE_WATCHDOG)
+
+  // Initialize watchdog - On SAM3X, Watchdog was already configured
+  //  and enabled or disabled at startup, so no need to reconfigure it
+  //  here.
+  void MarlinHAL::watchdog_init() { WDT_Restart(WDT); } // Reset watchdog to start clean
+
+  // Reset watchdog. MUST be called at least every 4 seconds after the
+  // first watchdog_init or AVR will go into emergency procedures.
+  void MarlinHAL::watchdog_refresh() { watchdogReset(); }
+
+#endif
+
+// Override Arduino runtime to either config or disable the watchdog
+//
+// We need to configure the watchdog as soon as possible in the boot
+// process, because watchdog initialization at hardware reset on SAM3X8E
+// is unreliable, and there is risk of unintended resets if we delay
+// that initialization to a later time.
+void watchdogSetup() {
+
+  #if ENABLED(USE_WATCHDOG)
+
+    // 4 seconds timeout
+    uint32_t timeout = TERN(WATCHDOG_DURATION_8S, 8000, 4000);
+
+    // Calculate timeout value in WDT counter ticks: This assumes
+    // the slow clock is running at 32.768 kHz watchdog
+    // frequency is therefore 32768 / 128 = 256 Hz
+    timeout = (timeout << 8) / 1000;
+    if (timeout == 0)
+      timeout = 1;
+    else if (timeout > 0xFFF)
+      timeout = 0xFFF;
+
+    // We want to enable the watchdog with the specified timeout
+    uint32_t value =
+      WDT_MR_WDV(timeout) |               // With the specified timeout
+      WDT_MR_WDD(timeout) |               // and no invalid write window
+    #if !(SAMV70 || SAMV71 || SAME70 || SAMS70)
+      WDT_MR_WDRPROC   |                  // WDT fault resets processor only - We want
+                                          // to keep PIO controller state
+    #endif
+      WDT_MR_WDDBGHLT  |                  // WDT stops in debug state.
+      WDT_MR_WDIDLEHLT;                   // WDT stops in idle state.
+
+    #if ENABLED(WATCHDOG_RESET_MANUAL)
+      // We enable the watchdog timer, but only for the interrupt.
+
+      // Configure WDT to only trigger an interrupt
+      value |= WDT_MR_WDFIEN;             // Enable WDT fault interrupt.
+
+      // Disable WDT interrupt (just in case, to avoid triggering it!)
+      NVIC_DisableIRQ(WDT_IRQn);
+
+      // We NEED memory barriers to ensure Interrupts are actually disabled!
+      // ( https://dzone.com/articles/nvic-disabling-interrupts-on-arm-cortex-m-and-the )
+      __DSB();
+      __ISB();
+
+      // Initialize WDT with the given parameters
+      WDT_Enable(WDT, value);
+
+      // Configure and enable WDT interrupt.
+      NVIC_ClearPendingIRQ(WDT_IRQn);
+      NVIC_SetPriority(WDT_IRQn, 0); // Use highest priority, so we detect all kinds of lockups
+      NVIC_EnableIRQ(WDT_IRQn);
+
+    #else
+
+      // a WDT fault triggers a reset
+      value |= WDT_MR_WDRSTEN;
+
+      // Initialize WDT with the given parameters
+      WDT_Enable(WDT, value);
+
+    #endif
+
+    // Reset the watchdog
+    WDT_Restart(WDT);
+
+  #else
+
+    // Make sure to completely disable the Watchdog
+    WDT_Disable(WDT);
+
+  #endif
 }

+// ------------------------
+// Free Memory Accessor
+// ------------------------
+
 extern "C" {
  extern unsigned int _ebss; // end of bss section
 }
@@ -95,18 +181,9 @@ int freeMemory() {
 }

 // ------------------------
-// ADC
+// Serial Ports
 // ------------------------

-void HAL_adc_start_conversion(const uint8_t ch) {
-  HAL_adc_result = analogRead(ch);
-}
-
-uint16_t HAL_adc_get_result() {
-  // nop
-  return HAL_adc_result;
-}
-
 // Forward the default serial ports
 #if USING_HW_SERIAL0
  DefaultSerial1 MSerial0(false, Serial);
@@ -32,12 +32,15 @@
 #include "../shared/math_32bit.h"
 #include "../shared/HAL_SPI.h"
 #include "fastio.h"
-#include "watchdog.h"

 #include <stdint.h>

 #include "../../core/serial_hook.h"

+// ------------------------
+// Serial ports
+// ------------------------
+
 typedef ForwardSerial1Class< decltype(Serial) > DefaultSerial1;
 typedef ForwardSerial1Class< decltype(Serial1) > DefaultSerial2;
 typedef ForwardSerial1Class< decltype(Serial2) > DefaultSerial3;
@@ -97,55 +100,38 @@ extern DefaultSerial4 MSerial3;
 #include "MarlinSerial.h"
 #include "MarlinSerialUSB.h"

-// On AVR this is in math.h?
-#define square(x) ((x)*(x))
+// ------------------------
+// Types
+// ------------------------

 typedef int8_t pin_t;

-#define SHARED_SERVOS HAS_SERVOS
-#define HAL_SERVO_LIB Servo
+#define SHARED_SERVOS HAS_SERVOS  // Use shared/servos.cpp
+
+class Servo;
+typedef Servo hal_servo_t;

 //
 // Interrupts
 //
-#define CRITICAL_SECTION_START()  uint32_t primask = __get_PRIMASK(); __disable_irq()
-#define CRITICAL_SECTION_END()    if (!primask) __enable_irq()
-#define ISRS_ENABLED() (!__get_PRIMASK())
-#define ENABLE_ISRS()  __enable_irq()
-#define DISABLE_ISRS() __disable_irq()
+#define sei() interrupts()
+#define cli() noInterrupts()

-void cli();                     // Disable interrupts
-void sei();                     // Enable interrupts
-
-void HAL_clear_reset_source();  // clear reset reason
-uint8_t HAL_get_reset_source(); // get reset reason
-
-void HAL_reboot();
+#define CRITICAL_SECTION_START()  const bool _irqon = hal.isr_state(); hal.isr_off()
+#define CRITICAL_SECTION_END()    if (_irqon) hal.isr_on()

 //
 // ADC
 //
-extern uint16_t HAL_adc_result;     // result of last ADC conversion
+#define HAL_ADC_VREF         3.3
+#define HAL_ADC_RESOLUTION  10

 #ifndef analogInputToDigitalPin
  #define analogInputToDigitalPin(p) ((p < 12U) ? (p) + 54U : -1)
 #endif

-#define HAL_ANALOG_SELECT(ch)
-
-inline void HAL_adc_init() {}//todo
-
-#define HAL_ADC_VREF         3.3
-#define HAL_ADC_RESOLUTION  10
-#define HAL_START_ADC(ch)   HAL_adc_start_conversion(ch)
-#define HAL_READ_ADC()      HAL_adc_result
-#define HAL_ADC_READY()     true
-
-void HAL_adc_start_conversion(const uint8_t ch);
-uint16_t HAL_adc_get_result();
-
 //
-// Pin Map
+// Pin Mapping for M42, M43, M226
 //
 #define GET_PIN_MAP_PIN(index) index
 #define GET_PIN_MAP_INDEX(pin) pin
@@ -154,30 +140,19 @@ uint16_t HAL_adc_get_result();
 //
 // Tone
 //
-void toneInit();
 void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration=0);
 void noTone(const pin_t _pin);

-// Enable hooks into idle and setup for HAL
-#define HAL_IDLETASK 1
-void HAL_idletask();
-void HAL_init();
-
-//
-// Utility functions
-//
-void _delay_ms(const int delay);
+// ------------------------
+// Class Utilities
+// ------------------------

+#pragma GCC diagnostic push
 #if GCC_VERSION <= 50000
-  #pragma GCC diagnostic push
  #pragma GCC diagnostic ignored "-Wunused-function"
 #endif

-int freeMemory();
-
-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic pop
-#endif
+#pragma GCC diagnostic pop

 #ifdef __cplusplus
  extern "C" {
@@ -186,3 +161,73 @@ char *dtostrf(double __val, signed char __width, unsigned char __prec, char *__s
 #ifdef __cplusplus
  }
 #endif
+
+// Return free RAM between end of heap (or end bss) and whatever is current
+int freeMemory();
+
+// ------------------------
+// MarlinHAL Class
+// ------------------------
+
+class MarlinHAL {
+public:
+
+  // Earliest possible init, before setup()
+  MarlinHAL() {}
+
+  // Watchdog
+  static void watchdog_init()    IF_DISABLED(USE_WATCHDOG, {});
+  static void watchdog_refresh() IF_DISABLED(USE_WATCHDOG, {});
+
+  static void init();          // Called early in setup()
+  static void init_board();    // Called less early in setup()
+  static void reboot();        // Restart the firmware
+
+  // Interrupts
+  static bool isr_state() { return !__get_PRIMASK(); }
+  static void isr_on()  { __enable_irq(); }
+  static void isr_off() { __disable_irq(); }
+
+  static void delay_ms(const int ms) { delay(ms); }
+
+  // Tasks, called from idle()
+  static void idletask();
+
+  // Reset
+  static uint8_t get_reset_source();
+  static void clear_reset_source() {}
+
+  // Free SRAM
+  static int freeMemory() { return ::freeMemory(); }
+
+  //
+  // ADC Methods
+  //
+
+  static uint16_t adc_result;
+
+  // Called by Temperature::init once at startup
+  static void adc_init() {}
+
+  // Called by Temperature::init for each sensor at startup
+  static void adc_enable(const uint8_t ch) {}
+
+  // Begin ADC sampling on the given channel. Called from Temperature::isr!
+  static void adc_start(const uint8_t ch) { adc_result = analogRead(ch); }
+
+  // Is the ADC ready for reading?
+  static bool adc_ready() { return true; }
+
+  // The current value of the ADC register
+  static uint16_t adc_value() { return adc_result; }
+
+  /**
+   * Set the PWM duty cycle for the pin to the given value.
+   * No inverting the duty cycle in this HAL.
+   * No changing the maximum size of the provided value to enable finer PWM duty control in this HAL.
+   */
+  static void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t=255, const bool=false) {
+    analogWrite(pin, v);
+  }
+
+};
@@ -31,8 +31,6 @@

 /**
 * HAL for Arduino Due and compatible (SAM3X8E)
- *
- * For ARDUINO_ARCH_SAM
 */

 #ifdef ARDUINO_ARCH_SAM
@@ -594,18 +592,14 @@
      SPI_Configure(SPI0, ID_SPI0, SPI_MR_MSTR | SPI_MR_MODFDIS | SPI_MR_PS);
      SPI_Enable(SPI0);

-      SET_OUTPUT(DAC0_SYNC);
+      SET_OUTPUT(DAC0_SYNC_PIN);
      #if HAS_MULTI_EXTRUDER
-        SET_OUTPUT(DAC1_SYNC);
-        WRITE(DAC1_SYNC, HIGH);
+        OUT_WRITE(DAC1_SYNC_PIN, HIGH);
      #endif
-      SET_OUTPUT(SPI_EEPROM1_CS);
-      SET_OUTPUT(SPI_EEPROM2_CS);
-      SET_OUTPUT(SPI_FLASH_CS);
-      WRITE(DAC0_SYNC, HIGH);
-      WRITE(SPI_EEPROM1_CS, HIGH);
-      WRITE(SPI_EEPROM2_CS, HIGH);
-      WRITE(SPI_FLASH_CS, HIGH);
+      WRITE(DAC0_SYNC_PIN, HIGH);
+      OUT_WRITE(SPI_EEPROM1_CS_PIN, HIGH);
+      OUT_WRITE(SPI_EEPROM2_CS_PIN, HIGH);
+      OUT_WRITE(SPI_FLASH_CS_PIN, HIGH);
      WRITE(SD_SS_PIN, HIGH);

      OUT_WRITE(SDSS, LOW);
@@ -1,6 +1,6 @@
 /**
 * Marlin 3D Printer Firmware
- * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2021 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
@@ -21,5 +21,6 @@
 */
 #pragma once

-void watchdog_init();
-void HAL_watchdog_refresh();
+#include <SPI.h>
+
+using MarlinSPI = SPIClass;
@@ -406,7 +406,7 @@ size_t MarlinSerial<Cfg>::write(const uint8_t c) {
    const uint8_t i = (tx_buffer.head + 1) & (Cfg::TX_SIZE - 1);

    // If global interrupts are disabled (as the result of being called from an ISR)...
-    if (!ISRS_ENABLED()) {
+    if (!hal.isr_state()) {

      // Make room by polling if it is possible to transmit, and do so!
      while (i == tx_buffer.tail) {
@@ -454,7 +454,7 @@ void MarlinSerial<Cfg>::flushTX() {
    if (!_written) return;

    // If global interrupts are disabled (as the result of being called from an ISR)...
-    if (!ISRS_ENABLED()) {
+    if (!hal.isr_state()) {

      // Wait until everything was transmitted - We must do polling, as interrupts are disabled
      while (tx_buffer.head != tx_buffer.tail || !(HWUART->UART_SR & UART_SR_TXEMPTY)) {
@@ -118,7 +118,7 @@ public:
  static size_t write(const uint8_t c);
  static void flushTX();

-  static inline bool emergency_parser_enabled() { return Cfg::EMERGENCYPARSER; }
+  static bool emergency_parser_enabled() { return Cfg::EMERGENCYPARSER; }

  FORCE_INLINE static uint8_t dropped() { return Cfg::DROPPED_RX ? rx_dropped_bytes : 0; }
  FORCE_INLINE static uint8_t buffer_overruns() { return Cfg::RX_OVERRUNS ? rx_buffer_overruns : 0; }
@@ -41,7 +41,7 @@ extern "C" {
  int udi_cdc_getc();
  bool udi_cdc_is_tx_ready();
  int udi_cdc_putc(int value);
-};
+}

 // Pending character
 static int pending_char = -1;
@@ -25,7 +25,7 @@

 #if ENABLED(POSTMORTEM_DEBUGGING)

-#include "../shared/HAL_MinSerial.h"
+#include "../shared/MinSerial.h"

 #include <stdarg.h>

@@ -35,20 +35,20 @@
 static pin_t tone_pin;
 volatile static int32_t toggles;

-void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration) {
+void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration/*=0*/) {
  tone_pin = _pin;
  toggles = 2 * frequency * duration / 1000;
-  HAL_timer_start(TONE_TIMER_NUM, 2 * frequency);
+  HAL_timer_start(MF_TIMER_TONE, 2 * frequency);
 }

 void noTone(const pin_t _pin) {
-  HAL_timer_disable_interrupt(TONE_TIMER_NUM);
+  HAL_timer_disable_interrupt(MF_TIMER_TONE);
  extDigitalWrite(_pin, LOW);
 }

 HAL_TONE_TIMER_ISR() {
  static uint8_t pin_state = 0;
-  HAL_timer_isr_prologue(TONE_TIMER_NUM);
+  HAL_timer_isr_prologue(MF_TIMER_TONE);

  if (toggles) {
    toggles--;
@@ -20,7 +20,6 @@
 *
 */

-
 /**
 * Based on u8g_com_msp430_hw_spi.c
 *
@@ -57,7 +57,7 @@

 #include "../../../inc/MarlinConfigPre.h"

-#if ENABLED(U8GLIB_ST7920)
+#if IS_U8GLIB_ST7920

 #include "../../../inc/MarlinConfig.h"
 #include "../../shared/Delay.h"
@@ -182,5 +182,5 @@ uint8_t u8g_com_HAL_DUE_ST7920_sw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_va
  }
 #endif // LIGHTWEIGHT_UI

-#endif // U8GLIB_ST7920
+#endif // IS_U8GLIB_ST7920
 #endif // ARDUINO_ARCH_SAM
@@ -57,7 +57,7 @@

 #include "../../../inc/MarlinConfigPre.h"

-#if HAS_MARLINUI_U8GLIB && DISABLED(U8GLIB_ST7920)
+#if HAS_MARLINUI_U8GLIB && !IS_U8GLIB_ST7920

 #include "u8g_com_HAL_DUE_sw_spi_shared.h"

@@ -141,5 +141,5 @@ uint8_t u8g_com_HAL_DUE_sw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void
  return 1;
 }

-#endif // HAS_MARLINUI_U8GLIB && !U8GLIB_ST7920
+#endif // HAS_MARLINUI_U8GLIB && !IS_U8GLIB_ST7920
 #endif // ARDUINO_ARCH_SAM
@@ -199,10 +199,9 @@ static bool ee_PageWrite(uint16_t page, const void *data) {
  for (i = 0; i <PageSize >> 2; i++)
    pageContents[i] = (((uint32_t*)data)[i]) | (~(pageContents[i] ^ ((uint32_t*)data)[i]));

-  DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM PageWrite   ", page);
-  DEBUG_ECHOLNPAIR(" in FLASH address ", (uint32_t)addrflash);
-  DEBUG_ECHOLNPAIR(" base address     ", (uint32_t)getFlashStorage(0));
+  DEBUG_ECHO_MSG("EEPROM PageWrite   ", page);
+  DEBUG_ECHOLNPGM(" in FLASH address ", (uint32_t)addrflash);
+  DEBUG_ECHOLNPGM(" base address     ", (uint32_t)getFlashStorage(0));
  DEBUG_FLUSH();

  // Get the page relative to the start of the EFC controller, and the EFC controller to use
@@ -245,8 +244,7 @@ static bool ee_PageWrite(uint16_t page, const void *data) {
    // Reenable interrupts
    __enable_irq();

-    DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Unlock failure for page ", page);
+    DEBUG_ECHO_MSG("EEPROM Unlock failure for page ", page);
    return false;
  }

@@ -270,8 +268,7 @@ static bool ee_PageWrite(uint16_t page, const void *data) {
    // Reenable interrupts
    __enable_irq();

-    DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Write failure for page ", page);
+    DEBUG_ECHO_MSG("EEPROM Write failure for page ", page);

    return false;
  }
@@ -286,8 +283,7 @@ static bool ee_PageWrite(uint16_t page, const void *data) {
  if (memcmp(getFlashStorage(page),data,PageSize)) {

    #ifdef EE_EMU_DEBUG
-      DEBUG_ECHO_START();
-      DEBUG_ECHOLNPAIR("EEPROM Verify Write failure for page ", page);
+      DEBUG_ECHO_MSG("EEPROM Verify Write failure for page ", page);

      ee_Dump( page, (uint32_t *)addrflash);
      ee_Dump(-page, data);
@@ -306,7 +302,7 @@ static bool ee_PageWrite(uint16_t page, const void *data) {
          }
        }
      }
-      DEBUG_ECHOLNPAIR("--> Differing bits: ", count);
+      DEBUG_ECHOLNPGM("--> Differing bits: ", count);
    #endif

    return false;
@@ -325,10 +321,9 @@ static bool ee_PageErase(uint16_t page) {
  uint16_t i;
  uint32_t addrflash = uint32_t(getFlashStorage(page));

-  DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM PageErase  ", page);
-  DEBUG_ECHOLNPAIR(" in FLASH address ", (uint32_t)addrflash);
-  DEBUG_ECHOLNPAIR(" base address     ", (uint32_t)getFlashStorage(0));
+  DEBUG_ECHO_MSG("EEPROM PageErase  ", page);
+  DEBUG_ECHOLNPGM(" in FLASH address ", (uint32_t)addrflash);
+  DEBUG_ECHOLNPGM(" base address     ", (uint32_t)getFlashStorage(0));
  DEBUG_FLUSH();

  // Get the page relative to the start of the EFC controller, and the EFC controller to use
@@ -370,8 +365,7 @@ static bool ee_PageErase(uint16_t page) {
    // Reenable interrupts
    __enable_irq();

-    DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Unlock failure for page ",page);
+    DEBUG_ECHO_MSG("EEPROM Unlock failure for page ",page);

    return false;
  }
@@ -394,8 +388,7 @@ static bool ee_PageErase(uint16_t page) {
    // Reenable interrupts
    __enable_irq();

-    DEBUG_ECHO_START();
-    DEBUG_ECHOLNPAIR("EEPROM Erase failure for page ",page);
+    DEBUG_ECHO_MSG("EEPROM Erase failure for page ",page);

    return false;
  }
@@ -410,8 +403,7 @@ static bool ee_PageErase(uint16_t page) {
  uint32_t * aligned_src = (uint32_t *) addrflash;
  for (i = 0; i < PageSize >> 2; i++) {
    if (*aligned_src++ != 0xFFFFFFFF) {
-      DEBUG_ECHO_START();
-      DEBUG_ECHOLNPAIR("EEPROM Verify Erase failure for page ",page);
+      DEBUG_ECHO_MSG("EEPROM Verify Erase failure for page ",page);
      ee_Dump(page, (uint32_t *)addrflash);
      return false;
    }
@@ -921,8 +913,7 @@ static void ee_Init() {
  // If all groups seem to be used, default to first group
  if (curGroup >= GroupCount) curGroup = 0;

-  DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM Current Group: ",curGroup);
+  DEBUG_ECHO_MSG("EEPROM Current Group: ",curGroup);
  DEBUG_FLUSH();

  // Now, validate that all the other group pages are empty
@@ -931,8 +922,7 @@ static void ee_Init() {

    for (int page = 0; page < PagesPerGroup; page++) {
      if (!ee_IsPageClean(grp * PagesPerGroup + page)) {
-        DEBUG_ECHO_START();
-        DEBUG_ECHOLNPAIR("EEPROM Page ", page, " not clean on group ", grp);
+        DEBUG_ECHO_MSG("EEPROM Page ", page, " not clean on group ", grp);
        DEBUG_FLUSH();
        ee_PageErase(grp * PagesPerGroup + page);
      }
@@ -948,15 +938,13 @@ static void ee_Init() {
    }
  }

-  DEBUG_ECHO_START();
-  DEBUG_ECHOLNPAIR("EEPROM Active page: ", curPage);
+  DEBUG_ECHO_MSG("EEPROM Active page: ", curPage);
  DEBUG_FLUSH();

  // Make sure the pages following the first clean one are also clean
  for (int page = curPage + 1; page < PagesPerGroup; page++) {
    if (!ee_IsPageClean(curGroup * PagesPerGroup + page)) {
-      DEBUG_ECHO_START();
-      DEBUG_ECHOLNPAIR("EEPROM Page ", page, " not clean on active group ", curGroup);
+      DEBUG_ECHO_MSG("EEPROM Page ", page, " not clean on active group ", curGroup);
      DEBUG_FLUSH();
      ee_Dump(curGroup * PagesPerGroup + page, getFlashStorage(curGroup * PagesPerGroup + page));
      ee_PageErase(curGroup * PagesPerGroup + page);
@@ -70,4 +70,10 @@ void setup_endstop_interrupts() {
  TERN_(HAS_J_MIN, _ATTACH(J_MIN_PIN));
  TERN_(HAS_K_MAX, _ATTACH(K_MAX_PIN));
  TERN_(HAS_K_MIN, _ATTACH(K_MIN_PIN));
+  TERN_(HAS_U_MAX, _ATTACH(U_MAX_PIN));
+  TERN_(HAS_U_MIN, _ATTACH(U_MIN_PIN));
+  TERN_(HAS_V_MAX, _ATTACH(V_MAX_PIN));
+  TERN_(HAS_V_MIN, _ATTACH(V_MIN_PIN));
+  TERN_(HAS_W_MAX, _ATTACH(W_MAX_PIN));
+  TERN_(HAS_W_MIN, _ATTACH(W_MIN_PIN));
 }
@@ -25,7 +25,7 @@
 * is NOT used to directly toggle pins. The ISR writes to the pin assigned to
 * that interrupt.
 *
- * All PWMs use the same repetition rate.  The G2 needs about 10KHz min in order to
+ * All PWMs use the same repetition rate.  The G2 needs about 10kHz min in order to
 * not have obvious ripple on the Vref signals.
 *
 * The data structures are setup to minimize the computation done by the ISR which
@@ -25,6 +25,30 @@
 * Test Arduino Due specific configuration values for errors at compile-time.
 */

+/**
+ * Check for common serial pin conflicts
+ */
+#define CHECK_SERIAL_PIN(N) ( \
+     X_STOP_PIN == N || Y_STOP_PIN == N || Z_STOP_PIN == N \
+  || X_MIN_PIN  == N || Y_MIN_PIN  == N || Z_MIN_PIN  == N \
+  || X_MAX_PIN  == N || Y_MAX_PIN  == N || Z_MAX_PIN  == N \
+  || X_STEP_PIN == N || Y_STEP_PIN == N || Z_STEP_PIN == N \
+  || X_DIR_PIN  == N || Y_DIR_PIN  == N || Z_DIR_PIN  == N \
+  || X_ENA_PIN  == N || Y_ENA_PIN  == N || Z_ENA_PIN  == N \
+)
+#if CONF_SERIAL_IS(0) // D0-D1. No known conflicts.
+#endif
+#if CONF_SERIAL_IS(1) && (CHECK_SERIAL_PIN(18) || CHECK_SERIAL_PIN(19))
+  #error "Serial Port 1 pin D18 and/or D19 conflicts with another pin on the board."
+#endif
+#if CONF_SERIAL_IS(2) && (CHECK_SERIAL_PIN(16) || CHECK_SERIAL_PIN(17))
+  #error "Serial Port 2 pin D16 and/or D17 conflicts with another pin on the board."
+#endif
+#if CONF_SERIAL_IS(3) && (CHECK_SERIAL_PIN(14) || CHECK_SERIAL_PIN(15))
+  #error "Serial Port 3 pin D14 and/or D15 conflicts with another pin on the board."
+#endif
+#undef CHECK_SERIAL_PIN
+
 /**
 * HARDWARE VS. SOFTWARE SPI COMPATIBILITY
 *
@@ -59,3 +83,7 @@
 #if HAS_TMC_SW_SERIAL
  #error "TMC220x Software Serial is not supported on the DUE platform."
 #endif
+
+#if USING_PULLDOWNS
+  #error "PULLDOWN pin mode is not available on DUE boards."
+#endif
@@ -2,6 +2,9 @@
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
@@ -50,7 +53,7 @@
 *     The net result is that both the g_pinStatus[pin] array and the PIO_OSR register
 *     needs to be looked at when determining if a pin is an input or an output.
 *
- * b) Due has only pins 6, 7, 8 & 9 enabled for PWMs.  FYI - they run at 1KHz
+ * b) Due has only pins 6, 7, 8 & 9 enabled for PWMs.  FYI - they run at 1kHz
 *
 * c) NUM_DIGITAL_PINS does not include the analog pins
 *
@@ -64,6 +67,7 @@
 #define PRINT_PORT(p)
 #define PRINT_ARRAY_NAME(x) do{ sprintf_P(buffer, PSTR("%-" STRINGIFY(MAX_NAME_LENGTH) "s"), pin_array[x].name); SERIAL_ECHO(buffer); }while(0)
 #define PRINT_PIN(p) do{ sprintf_P(buffer, PSTR("%02d"), p); SERIAL_ECHO(buffer); }while(0)
+#define PRINT_PIN_ANALOG(p) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), DIGITAL_PIN_TO_ANALOG_PIN(pin)); SERIAL_ECHO(buffer); }while(0)
 #define GET_ARRAY_PIN(p) pin_array[p].pin
 #define GET_ARRAY_IS_DIGITAL(p) pin_array[p].is_digital
 #define VALID_PIN(pin) (pin >= 0 && pin < (int8_t)NUMBER_PINS_TOTAL ? 1 : 0)
@@ -82,11 +86,10 @@ bool GET_PINMODE(int8_t pin) {  // 1: output, 0: input
          || pwm_status(pin));
 }

-
 void pwm_details(int32_t pin) {
  if (pwm_status(pin)) {
    uint32_t chan = g_APinDescription[pin].ulPWMChannel;
-    SERIAL_ECHOPAIR("PWM = ", PWM_INTERFACE->PWM_CH_NUM[chan].PWM_CDTY);
+    SERIAL_ECHOPGM("PWM = ", PWM_INTERFACE->PWM_CH_NUM[chan].PWM_CDTY);
  }
 }

@@ -42,7 +42,7 @@
 // Private Variables
 // ------------------------

-const tTimerConfig TimerConfig [NUM_HARDWARE_TIMERS] = {
+const tTimerConfig timer_config[NUM_HARDWARE_TIMERS] = {
  { TC0, 0, TC0_IRQn,  3}, // 0 - [servo timer5]
  { TC0, 1, TC1_IRQn,  0}, // 1
  { TC0, 2, TC2_IRQn,  2}, // 2 - stepper
@@ -66,9 +66,9 @@ const tTimerConfig TimerConfig [NUM_HARDWARE_TIMERS] = {
 */

 void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency) {
-  Tc *tc = TimerConfig[timer_num].pTimerRegs;
-  IRQn_Type irq = TimerConfig[timer_num].IRQ_Id;
-  uint32_t channel = TimerConfig[timer_num].channel;
+  Tc *tc = timer_config[timer_num].pTimerRegs;
+  IRQn_Type irq = timer_config[timer_num].IRQ_Id;
+  uint32_t channel = timer_config[timer_num].channel;

  // Disable interrupt, just in case it was already enabled
  NVIC_DisableIRQ(irq);
@@ -86,7 +86,7 @@ void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency) {

  pmc_set_writeprotect(false);
  pmc_enable_periph_clk((uint32_t)irq);
-  NVIC_SetPriority(irq, TimerConfig [timer_num].priority);
+  NVIC_SetPriority(irq, timer_config[timer_num].priority);

  // wave mode, reset counter on match with RC,
  TC_Configure(tc, channel, TC_CMR_WAVE | TC_CMR_WAVSEL_UP_RC | TC_CMR_TCCLKS_TIMER_CLOCK1);
@@ -105,12 +105,12 @@ void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency) {
 }

 void HAL_timer_enable_interrupt(const uint8_t timer_num) {
-  IRQn_Type irq = TimerConfig[timer_num].IRQ_Id;
+  IRQn_Type irq = timer_config[timer_num].IRQ_Id;
  NVIC_EnableIRQ(irq);
 }

 void HAL_timer_disable_interrupt(const uint8_t timer_num) {
-  IRQn_Type irq = TimerConfig[timer_num].IRQ_Id;
+  IRQn_Type irq = timer_config[timer_num].IRQ_Id;
  NVIC_DisableIRQ(irq);

  // We NEED memory barriers to ensure Interrupts are actually disabled!
@@ -125,7 +125,7 @@ static bool NVIC_GetEnabledIRQ(IRQn_Type IRQn) {
 }

 bool HAL_timer_interrupt_enabled(const uint8_t timer_num) {
-  IRQn_Type irq = TimerConfig[timer_num].IRQ_Id;
+  IRQn_Type irq = timer_config[timer_num].IRQ_Id;
  return NVIC_GetEnabledIRQ(irq);
 }

@@ -37,35 +37,35 @@ typedef uint32_t hal_timer_t;

 #define HAL_TIMER_RATE         ((F_CPU) / 2)    // frequency of timers peripherals

-#ifndef STEP_TIMER_NUM
-  #define STEP_TIMER_NUM        2  // Timer Index for Stepper
+#ifndef MF_TIMER_STEP
+  #define MF_TIMER_STEP         2  // Timer Index for Stepper
 #endif
-#ifndef PULSE_TIMER_NUM
-  #define PULSE_TIMER_NUM       STEP_TIMER_NUM
+#ifndef MF_TIMER_PULSE
+  #define MF_TIMER_PULSE        MF_TIMER_STEP
 #endif
-#ifndef TEMP_TIMER_NUM
-  #define TEMP_TIMER_NUM        4  // Timer Index for Temperature
+#ifndef MF_TIMER_TEMP
+  #define MF_TIMER_TEMP         4  // Timer Index for Temperature
 #endif
-#ifndef TONE_TIMER_NUM
-  #define TONE_TIMER_NUM        6  // index of timer to use for beeper tones
+#ifndef MF_TIMER_TONE
+  #define MF_TIMER_TONE         6  // index of timer to use for beeper tones
 #endif

 #define TEMP_TIMER_FREQUENCY   1000 // temperature interrupt frequency

-#define STEPPER_TIMER_RATE     HAL_TIMER_RATE   // frequency of stepper timer (HAL_TIMER_RATE / STEPPER_TIMER_PRESCALE)
-#define STEPPER_TIMER_TICKS_PER_US ((STEPPER_TIMER_RATE) / 1000000) // stepper timer ticks per µs
-#define STEPPER_TIMER_PRESCALE (CYCLES_PER_MICROSECOND / STEPPER_TIMER_TICKS_PER_US)
+#define STEPPER_TIMER_RATE          HAL_TIMER_RATE                                        // frequency of stepper timer (HAL_TIMER_RATE / STEPPER_TIMER_PRESCALE)
+#define STEPPER_TIMER_TICKS_PER_US  ((STEPPER_TIMER_RATE) / 1000000)                      // stepper timer ticks per µs
+#define STEPPER_TIMER_PRESCALE      (CYCLES_PER_MICROSECOND / STEPPER_TIMER_TICKS_PER_US)

-#define PULSE_TIMER_RATE       STEPPER_TIMER_RATE   // frequency of pulse timer
-#define PULSE_TIMER_PRESCALE   STEPPER_TIMER_PRESCALE
-#define PULSE_TIMER_TICKS_PER_US STEPPER_TIMER_TICKS_PER_US
+#define PULSE_TIMER_RATE            STEPPER_TIMER_RATE                                    // frequency of pulse timer
+#define PULSE_TIMER_PRESCALE        STEPPER_TIMER_PRESCALE
+#define PULSE_TIMER_TICKS_PER_US    STEPPER_TIMER_TICKS_PER_US

-#define ENABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_enable_interrupt(STEP_TIMER_NUM)
-#define DISABLE_STEPPER_DRIVER_INTERRUPT()  HAL_timer_disable_interrupt(STEP_TIMER_NUM)
-#define STEPPER_ISR_ENABLED() HAL_timer_interrupt_enabled(STEP_TIMER_NUM)
+#define ENABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_enable_interrupt(MF_TIMER_STEP)
+#define DISABLE_STEPPER_DRIVER_INTERRUPT()  HAL_timer_disable_interrupt(MF_TIMER_STEP)
+#define STEPPER_ISR_ENABLED() HAL_timer_interrupt_enabled(MF_TIMER_STEP)

-#define ENABLE_TEMPERATURE_INTERRUPT()  HAL_timer_enable_interrupt(TEMP_TIMER_NUM)
-#define DISABLE_TEMPERATURE_INTERRUPT() HAL_timer_disable_interrupt(TEMP_TIMER_NUM)
+#define ENABLE_TEMPERATURE_INTERRUPT()  HAL_timer_enable_interrupt(MF_TIMER_TEMP)
+#define DISABLE_TEMPERATURE_INTERRUPT() HAL_timer_disable_interrupt(MF_TIMER_TEMP)

 #ifndef HAL_STEP_TIMER_ISR
  #define HAL_STEP_TIMER_ISR() void TC2_Handler()
@@ -92,7 +92,7 @@ typedef struct {
 // Public Variables
 // ------------------------

-extern const tTimerConfig TimerConfig[];
+extern const tTimerConfig timer_config[];

 // ------------------------
 // Public functions
@@ -101,17 +101,17 @@ extern const tTimerConfig TimerConfig[];
 void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency);

 FORCE_INLINE static void HAL_timer_set_compare(const uint8_t timer_num, const hal_timer_t compare) {
-  const tTimerConfig * const pConfig = &TimerConfig[timer_num];
+  const tTimerConfig * const pConfig = &timer_config[timer_num];
  pConfig->pTimerRegs->TC_CHANNEL[pConfig->channel].TC_RC = compare;
 }

 FORCE_INLINE static hal_timer_t HAL_timer_get_compare(const uint8_t timer_num) {
-  const tTimerConfig * const pConfig = &TimerConfig[timer_num];
+  const tTimerConfig * const pConfig = &timer_config[timer_num];
  return pConfig->pTimerRegs->TC_CHANNEL[pConfig->channel].TC_RC;
 }

 FORCE_INLINE static hal_timer_t HAL_timer_get_count(const uint8_t timer_num) {
-  const tTimerConfig * const pConfig = &TimerConfig[timer_num];
+  const tTimerConfig * const pConfig = &timer_config[timer_num];
  return pConfig->pTimerRegs->TC_CHANNEL[pConfig->channel].TC_CV;
 }

@@ -120,9 +120,9 @@ void HAL_timer_disable_interrupt(const uint8_t timer_num);
 bool HAL_timer_interrupt_enabled(const uint8_t timer_num);

 FORCE_INLINE static void HAL_timer_isr_prologue(const uint8_t timer_num) {
-  const tTimerConfig * const pConfig = &TimerConfig[timer_num];
+  const tTimerConfig * const pConfig = &timer_config[timer_num];
  // Reading the status register clears the interrupt flag
  pConfig->pTimerRegs->TC_CHANNEL[pConfig->channel].TC_SR;
 }

-#define HAL_timer_isr_epilogue(TIMER_NUM)
+#define HAL_timer_isr_epilogue(T) NOOP
@@ -4,15 +4,16 @@
 #  Windows: bossac.exe
 #  Other: leave unchanged
 #
+import pioutil
+if pioutil.is_pio_build():
+	import platform
+	current_OS = platform.system()

-import platform
-current_OS = platform.system()
+	if current_OS == 'Windows':

-if current_OS == 'Windows':
+		Import("env")

-	Import("env")
-
-	# Use bossac.exe on Windows
-	env.Replace(
-	    UPLOADCMD="bossac --info --unlock --write --verify --reset --erase -U false --boot $SOURCE"
-	)
+		# Use bossac.exe on Windows
+		env.Replace(
+			UPLOADCMD="bossac --info --unlock --write --verify --reset --erase -U false --boot $SOURCE"
+		)
@@ -10,7 +10,7 @@

 #include "../../../sd/cardreader.h"
 extern "C" {
-#include "sd_mmc_spi_mem.h"
+  #include "sd_mmc_spi_mem.h"
 }

 #define SD_MMC_BLOCK_SIZE 512
@@ -1,114 +0,0 @@
-/**
- * Marlin 3D Printer Firmware
- * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
- *
- * Based on Sprinter and grbl.
- * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- *
- */
-#ifdef ARDUINO_ARCH_SAM
-
-#include "../../inc/MarlinConfig.h"
-#include "../../MarlinCore.h"
-#include "watchdog.h"
-
-// Override Arduino runtime to either config or disable the watchdog
-//
-// We need to configure the watchdog as soon as possible in the boot
-// process, because watchdog initialization at hardware reset on SAM3X8E
-// is unreliable, and there is risk of unintended resets if we delay
-// that initialization to a later time.
-void watchdogSetup() {
-
-  #if ENABLED(USE_WATCHDOG)
-
-    // 4 seconds timeout
-    uint32_t timeout = TERN(WATCHDOG_DURATION_8S, 8000, 4000);
-
-    // Calculate timeout value in WDT counter ticks: This assumes
-    // the slow clock is running at 32.768 kHz watchdog
-    // frequency is therefore 32768 / 128 = 256 Hz
-    timeout = (timeout << 8) / 1000;
-    if (timeout == 0)
-      timeout = 1;
-    else if (timeout > 0xFFF)
-      timeout = 0xFFF;
-
-    // We want to enable the watchdog with the specified timeout
-    uint32_t value =
-      WDT_MR_WDV(timeout) |               // With the specified timeout
-      WDT_MR_WDD(timeout) |               // and no invalid write window
-    #if !(SAMV70 || SAMV71 || SAME70 || SAMS70)
-      WDT_MR_WDRPROC   |                  // WDT fault resets processor only - We want
-                                          // to keep PIO controller state
-    #endif
-      WDT_MR_WDDBGHLT  |                  // WDT stops in debug state.
-      WDT_MR_WDIDLEHLT;                   // WDT stops in idle state.
-
-    #if ENABLED(WATCHDOG_RESET_MANUAL)
-      // We enable the watchdog timer, but only for the interrupt.
-
-      // Configure WDT to only trigger an interrupt
-      value |= WDT_MR_WDFIEN;             // Enable WDT fault interrupt.
-
-      // Disable WDT interrupt (just in case, to avoid triggering it!)
-      NVIC_DisableIRQ(WDT_IRQn);
-
-      // We NEED memory barriers to ensure Interrupts are actually disabled!
-      // ( https://dzone.com/articles/nvic-disabling-interrupts-on-arm-cortex-m-and-the )
-      __DSB();
-      __ISB();
-
-      // Initialize WDT with the given parameters
-      WDT_Enable(WDT, value);
-
-      // Configure and enable WDT interrupt.
-      NVIC_ClearPendingIRQ(WDT_IRQn);
-      NVIC_SetPriority(WDT_IRQn, 0); // Use highest priority, so we detect all kinds of lockups
-      NVIC_EnableIRQ(WDT_IRQn);
-
-    #else
-
-      // a WDT fault triggers a reset
-      value |= WDT_MR_WDRSTEN;
-
-      // Initialize WDT with the given parameters
-      WDT_Enable(WDT, value);
-
-    #endif
-
-    // Reset the watchdog
-    WDT_Restart(WDT);
-
-  #else
-
-    // Make sure to completely disable the Watchdog
-    WDT_Disable(WDT);
-
-  #endif
-}
-
-#if ENABLED(USE_WATCHDOG)
-  // Initialize watchdog - On SAM3X, Watchdog was already configured
-  //  and enabled or disabled at startup, so no need to reconfigure it
-  //  here.
-  void watchdog_init() {
-    // Reset watchdog to start clean
-    WDT_Restart(WDT);
-  }
-#endif // USE_WATCHDOG
-
-#endif
@@ -28,6 +28,10 @@
 #include <esp_adc_cal.h>
 #include <HardwareSerial.h>

+#if ENABLED(USE_ESP32_TASK_WDT)
+  #include <esp_task_wdt.h>
+#endif
+
 #if ENABLED(WIFISUPPORT)
  #include <ESPAsyncWebServer.h>
  #include "wifi.h"
@@ -48,7 +52,7 @@
 // Externs
 // ------------------------

-portMUX_TYPE spinlock = portMUX_INITIALIZER_UNLOCKED;
+portMUX_TYPE MarlinHAL::spinlock = portMUX_INITIALIZER_UNLOCKED;

 // ------------------------
 // Local defines
@@ -60,7 +64,7 @@ portMUX_TYPE spinlock = portMUX_INITIALIZER_UNLOCKED;
 // Public Variables
 // ------------------------

-uint16_t HAL_adc_result;
+uint16_t MarlinHAL::adc_result;

 // ------------------------
 // Private Variables
@@ -69,9 +73,16 @@ uint16_t HAL_adc_result;
 esp_adc_cal_characteristics_t characteristics[ADC_ATTEN_MAX];
 adc_atten_t attenuations[ADC1_CHANNEL_MAX] = {};
 uint32_t thresholds[ADC_ATTEN_MAX];
-volatile int numPWMUsed = 0,
-             pwmPins[MAX_PWM_PINS],
-             pwmValues[MAX_PWM_PINS];
+
+volatile int numPWMUsed = 0;
+volatile struct { pin_t pin; int value; } pwmState[MAX_PWM_PINS];
+
+pin_t chan_pin[CHANNEL_MAX_NUM + 1] = { 0 }; // PWM capable IOpins - not 0 or >33 on ESP32
+
+struct {
+  uint32_t freq; // ledcReadFreq doesn't work if a duty hasn't been set yet!
+  uint16_t res;
+} pwmInfo[(CHANNEL_MAX_NUM + 1) / 2];

 // ------------------------
 // Public functions
@@ -90,8 +101,26 @@ volatile int numPWMUsed = 0,

 #endif

-void HAL_init_board() {
+#if ENABLED(USE_ESP32_EXIO)

+  HardwareSerial YSerial2(2);
+
+  void Write_EXIO(uint8_t IO, uint8_t v) {
+    if (hal.isr_state()) {
+      hal.isr_off();
+      YSerial2.write(0x80 | (((char)v) << 5) | (IO - 100));
+      hal.isr_on();
+    }
+    else
+      YSerial2.write(0x80 | (((char)v) << 5) | (IO - 100));
+  }
+
+#endif
+
+void MarlinHAL::init_board() {
+  #if ENABLED(USE_ESP32_TASK_WDT)
+    esp_task_wdt_init(10, true);
+  #endif
  #if ENABLED(ESP3D_WIFISUPPORT)
    esp3dlib.init();
  #elif ENABLED(WIFISUPPORT)
@@ -127,30 +156,58 @@ void HAL_init_board() {
  // Initialize the i2s peripheral only if the I2S stepper stream is enabled.
  // The following initialization is performed after Serial1 and Serial2 are defined as
  // their native pins might conflict with the i2s stream even when they are remapped.
-  TERN_(I2S_STEPPER_STREAM, i2s_init());
+  #if ENABLED(USE_ESP32_EXIO)
+    YSerial2.begin(460800 * 3, SERIAL_8N1, 16, 17);
+  #elif ENABLED(I2S_STEPPER_STREAM)
+    i2s_init();
+  #endif
 }

-void HAL_idletask() {
+void MarlinHAL::idletask() {
  #if BOTH(WIFISUPPORT, OTASUPPORT)
    OTA_handle();
  #endif
  TERN_(ESP3D_WIFISUPPORT, esp3dlib.idletask());
 }

-void HAL_clear_reset_source() { }
+uint8_t MarlinHAL::get_reset_source() { return rtc_get_reset_reason(1); }

-uint8_t HAL_get_reset_source() { return rtc_get_reset_reason(1); }
-
-void HAL_reboot() { ESP.restart(); }
+void MarlinHAL::reboot() { ESP.restart(); }

 void _delay_ms(int delay_ms) { delay(delay_ms); }

 // return free memory between end of heap (or end bss) and whatever is current
-int freeMemory() { return ESP.getFreeHeap(); }
+int MarlinHAL::freeMemory() { return ESP.getFreeHeap(); }
+
+// ------------------------
+// Watchdog Timer
+// ------------------------
+
+#if ENABLED(USE_WATCHDOG)
+
+  #define WDT_TIMEOUT_US TERN(WATCHDOG_DURATION_8S, 8000000, 4000000) // 4 or 8 second timeout
+
+  extern "C" {
+    esp_err_t esp_task_wdt_reset();
+  }
+
+  void watchdogSetup() {
+    // do whatever. don't remove this function.
+  }
+
+  void MarlinHAL::watchdog_init() {
+    // TODO
+  }
+
+  // Reset watchdog.
+  void MarlinHAL::watchdog_refresh() { esp_task_wdt_reset(); }
+
+#endif

 // ------------------------
 // ADC
 // ------------------------
+
 #define ADC1_CHANNEL(pin) ADC1_GPIO ## pin ## _CHANNEL

 adc1_channel_t get_channel(int pin) {
@@ -172,22 +229,24 @@ void adc1_set_attenuation(adc1_channel_t chan, adc_atten_t atten) {
  }
 }

-void HAL_adc_init() {
+void MarlinHAL::adc_init() {
  // Configure ADC
  adc1_config_width(ADC_WIDTH_12Bit);

  // Configure channels only if used as (re-)configuring a pin for ADC that is used elsewhere might have adverse effects
-  TERN_(HAS_TEMP_ADC_0, adc1_set_attenuation(get_channel(TEMP_0_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_ADC_1, adc1_set_attenuation(get_channel(TEMP_1_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_ADC_2, adc1_set_attenuation(get_channel(TEMP_2_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_ADC_3, adc1_set_attenuation(get_channel(TEMP_3_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_ADC_4, adc1_set_attenuation(get_channel(TEMP_4_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_ADC_5, adc1_set_attenuation(get_channel(TEMP_5_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_ADC_6, adc2_set_attenuation(get_channel(TEMP_6_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_ADC_7, adc3_set_attenuation(get_channel(TEMP_7_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_HEATED_BED, adc1_set_attenuation(get_channel(TEMP_BED_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_CHAMBER, adc1_set_attenuation(get_channel(TEMP_CHAMBER_PIN), ADC_ATTEN_11db));
-  TERN_(HAS_TEMP_COOLER, adc1_set_attenuation(get_channel(TEMP_COOLER_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_0,        adc1_set_attenuation(get_channel(TEMP_0_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_1,        adc1_set_attenuation(get_channel(TEMP_1_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_2,        adc1_set_attenuation(get_channel(TEMP_2_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_3,        adc1_set_attenuation(get_channel(TEMP_3_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_4,        adc1_set_attenuation(get_channel(TEMP_4_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_5,        adc1_set_attenuation(get_channel(TEMP_5_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_6,        adc2_set_attenuation(get_channel(TEMP_6_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_ADC_7,        adc3_set_attenuation(get_channel(TEMP_7_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_HEATED_BED,        adc1_set_attenuation(get_channel(TEMP_BED_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_CHAMBER,      adc1_set_attenuation(get_channel(TEMP_CHAMBER_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_PROBE,        adc1_set_attenuation(get_channel(TEMP_PROBE_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_COOLER,       adc1_set_attenuation(get_channel(TEMP_COOLER_PIN), ADC_ATTEN_11db));
+  TERN_(HAS_TEMP_BOARD,        adc1_set_attenuation(get_channel(TEMP_BOARD_PIN), ADC_ATTEN_11db));
  TERN_(FILAMENT_WIDTH_SENSOR, adc1_set_attenuation(get_channel(FILWIDTH_PIN), ADC_ATTEN_11db));

  // Note that adc2 is shared with the WiFi module, which has higher priority, so the conversion may fail.
@@ -202,11 +261,16 @@ void HAL_adc_init() {
  }
 }

-void HAL_adc_start_conversion(const uint8_t adc_pin) {
-  const adc1_channel_t chan = get_channel(adc_pin);
+#ifndef ADC_REFERENCE_VOLTAGE
+  #define ADC_REFERENCE_VOLTAGE 3.3
+#endif
+
+void MarlinHAL::adc_start(const pin_t pin) {
+  const adc1_channel_t chan = get_channel(pin);
  uint32_t mv;
  esp_adc_cal_get_voltage((adc_channel_t)chan, &characteristics[attenuations[chan]], &mv);
-  HAL_adc_result = mv * 1023.0 / 3300.0;
+
+  adc_result = mv * isr_float_t(1023) / isr_float_t(ADC_REFERENCE_VOLTAGE) / isr_float_t(1000);

  // Change the attenuation level based on the new reading
  adc_atten_t atten;
@@ -223,25 +287,81 @@ void HAL_adc_start_conversion(const uint8_t adc_pin) {
  adc1_set_attenuation(chan, atten);
 }

-void analogWrite(pin_t pin, int value) {
-  // Use ledc hardware for internal pins
-  if (pin < 34) {
-    static int cnt_channel = 1, pin_to_channel[40] = { 0 };
-    if (pin_to_channel[pin] == 0) {
-      ledcAttachPin(pin, cnt_channel);
-      ledcSetup(cnt_channel, 490, 8);
-      ledcWrite(cnt_channel, value);
-      pin_to_channel[pin] = cnt_channel++;
+// ------------------------
+// PWM
+// ------------------------
+
+int8_t channel_for_pin(const uint8_t pin) {
+  for (int i = 0; i <= CHANNEL_MAX_NUM; i++)
+    if (chan_pin[i] == pin) return i;
+  return -1;
+}
+
+// get PWM channel for pin - if none then attach a new one
+// return -1 if fail or invalid pin#, channel # (0-15) if success
+int8_t get_pwm_channel(const pin_t pin, const uint32_t freq, const uint16_t res) {
+  if (!WITHIN(pin, 1, MAX_PWM_IOPIN)) return -1; // Not a hardware PWM pin!
+  int8_t cid = channel_for_pin(pin);
+  if (cid >= 0) return cid;
+
+  // Find an empty adjacent channel (same timer & freq/res)
+  for (int i = 0; i <= CHANNEL_MAX_NUM; i++) {
+    if (chan_pin[i] == 0) {
+      if (chan_pin[i ^ 0x1] != 0) {
+        if (pwmInfo[i / 2].freq == freq && pwmInfo[i / 2].res == res) {
+          chan_pin[i] = pin; // Allocate PWM to this channel
+          ledcAttachPin(pin, i);
+          return i;
+        }
+      }
+      else if (cid == -1)    // Pair of empty channels?
+        cid = i & 0xFE;      // Save lower channel number
    }
-    ledcWrite(pin_to_channel[pin], value);
+  }
+  // not attached, is an empty timer slot avail?
+  if (cid >= 0) {
+    chan_pin[cid] = pin;
+    pwmInfo[cid / 2].freq = freq;
+    pwmInfo[cid / 2].res = res;
+    ledcSetup(cid, freq, res);
+    ledcAttachPin(pin, cid);
+  }
+  return cid; // -1 if no channel avail
+}
+
+void MarlinHAL::set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=_BV(PWM_RESOLUTION)-1*/, const bool invert/*=false*/) {
+  const int8_t cid = get_pwm_channel(pin, PWM_FREQUENCY, PWM_RESOLUTION);
+  if (cid >= 0) {
+    uint32_t duty = map(invert ? v_size - v : v, 0, v_size, 0, _BV(PWM_RESOLUTION)-1);
+    ledcWrite(cid, duty);
+  }
+}
+
+int8_t MarlinHAL::set_pwm_frequency(const pin_t pin, const uint32_t f_desired) {
+  const int8_t cid = channel_for_pin(pin);
+  if (cid >= 0) {
+    if (f_desired == ledcReadFreq(cid)) return cid; // no freq change
+    ledcDetachPin(chan_pin[cid]);
+    chan_pin[cid] = 0;              // remove old freq channel
+  }
+  return get_pwm_channel(pin, f_desired, PWM_RESOLUTION); // try for new one
+}
+
+// use hardware PWM if avail, if not then ISR
+void analogWrite(const pin_t pin, const uint16_t value, const uint32_t freq/*=PWM_FREQUENCY*/, const uint16_t res/*=8*/) { // always 8 bit resolution!
+  // Use ledc hardware for internal pins
+  const int8_t cid = get_pwm_channel(pin, freq, res);
+  if (cid >= 0) {
+    ledcWrite(cid, value); // set duty value
    return;
  }

+  // not a hardware PWM pin OR no PWM channels available
  int idx = -1;

  // Search Pin
  for (int i = 0; i < numPWMUsed; ++i)
-    if (pwmPins[i] == pin) { idx = i; break; }
+    if (pwmState[i].pin == pin) { idx = i; break; }

  // not found ?
  if (idx < 0) {
@@ -250,34 +370,34 @@ void analogWrite(pin_t pin, int value) {

    // Take new slot for pin
    idx = numPWMUsed;
-    pwmPins[idx] = pin;
+    pwmState[idx].pin = pin;
    // Start timer on first use
-    if (idx == 0) HAL_timer_start(PWM_TIMER_NUM, PWM_TIMER_FREQUENCY);
+    if (idx == 0) HAL_timer_start(MF_TIMER_PWM, PWM_TIMER_FREQUENCY);

    ++numPWMUsed;
  }

  // Use 7bit internal value - add 1 to have 100% high at 255
-  pwmValues[idx] = (value + 1) / 2;
+  pwmState[idx].value = (value + 1) / 2;
 }

 // Handle PWM timer interrupt
 HAL_PWM_TIMER_ISR() {
-  HAL_timer_isr_prologue(PWM_TIMER_NUM);
+  HAL_timer_isr_prologue(MF_TIMER_PWM);

  static uint8_t count = 0;

  for (int i = 0; i < numPWMUsed; ++i) {
    if (count == 0)                   // Start of interval
-      WRITE(pwmPins[i], pwmValues[i] ? HIGH : LOW);
-    else if (pwmValues[i] == count)   // End of duration
-      WRITE(pwmPins[i], LOW);
+      digitalWrite(pwmState[i].pin, pwmState[i].value ? HIGH : LOW);
+    else if (pwmState[i].value == count)   // End of duration
+      digitalWrite(pwmState[i].pin, LOW);
  }

  // 128 for 7 Bit resolution
  count = (count + 1) & 0x7F;

-  HAL_timer_isr_epilogue(PWM_TIMER_NUM);
+  HAL_timer_isr_epilogue(MF_TIMER_PWM);
 }

 #endif // ARDUINO_ARCH_ESP32
@@ -32,7 +32,6 @@
 #include "../shared/HAL_SPI.h"

 #include "fastio.h"
-#include "watchdog.h"
 #include "i2s.h"

 #if ENABLED(WIFISUPPORT)
@@ -49,8 +48,6 @@
 // Defines
 // ------------------------

-extern portMUX_TYPE spinlock;
-
 #define MYSERIAL1 flushableSerial

 #if EITHER(WIFISUPPORT, ESP3D_WIFISUPPORT)
@@ -65,24 +62,22 @@ extern portMUX_TYPE spinlock;

 #define CRITICAL_SECTION_START() portENTER_CRITICAL(&spinlock)
 #define CRITICAL_SECTION_END()   portEXIT_CRITICAL(&spinlock)
-#define ISRS_ENABLED() (spinlock.owner == portMUX_FREE_VAL)
-#define ENABLE_ISRS()  if (spinlock.owner != portMUX_FREE_VAL) portEXIT_CRITICAL(&spinlock)
-#define DISABLE_ISRS() portENTER_CRITICAL(&spinlock)
+
+#define HAL_CAN_SET_PWM_FREQ   // This HAL supports PWM Frequency adjustment
+#define PWM_FREQUENCY  1000u   // Default PWM frequency when set_pwm_duty() is called without set_pwm_frequency()
+#define PWM_RESOLUTION   10u   // Default PWM bit resolution
+#define CHANNEL_MAX_NUM  15u   // max PWM channel # to allocate (7 to only use low speed, 15 to use low & high)
+#define MAX_PWM_IOPIN    33u   // hardware pwm pins < 34

 // ------------------------
 // Types
 // ------------------------

+typedef double isr_float_t;   // FPU ops are used for single-precision, so use double for ISRs.
 typedef int16_t pin_t;

-#define HAL_SERVO_LIB Servo
-
-// ------------------------
-// Public Variables
-// ------------------------
-
-/** result of last ADC conversion */
-extern uint16_t HAL_adc_result;
+class Servo;
+typedef Servo hal_servo_t;

 // ------------------------
 // Public functions
@@ -91,56 +86,21 @@ extern uint16_t HAL_adc_result;
 //
 // Tone
 //
-void toneInit();
 void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration=0);
 void noTone(const pin_t _pin);
+int8_t get_pwm_channel(const pin_t pin, const uint32_t freq, const uint16_t res);
+void analogWrite(const pin_t pin, const uint16_t value, const uint32_t freq=PWM_FREQUENCY, const uint16_t res=8);

-// clear reset reason
-void HAL_clear_reset_source();
-
-// reset reason
-uint8_t HAL_get_reset_source();
-
-void HAL_reboot();
-
-void _delay_ms(int delay);
-
-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic push
-  #pragma GCC diagnostic ignored "-Wunused-function"
-#endif
-
-int freeMemory();
-
-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic pop
-#endif
-
-void analogWrite(pin_t pin, int value);
-
-// ADC
-#define HAL_ANALOG_SELECT(pin)
-
-void HAL_adc_init();
-
-#define HAL_ADC_VREF         3.3
-#define HAL_ADC_RESOLUTION  10
-#define HAL_START_ADC(pin)  HAL_adc_start_conversion(pin)
-#define HAL_READ_ADC()      HAL_adc_result
-#define HAL_ADC_READY()     true
-
-void HAL_adc_start_conversion(const uint8_t adc_pin);
-
+//
+// Pin Mapping for M42, M43, M226
+//
 #define GET_PIN_MAP_PIN(index) index
 #define GET_PIN_MAP_INDEX(pin) pin
 #define PARSED_PIN_INDEX(code, dval) parser.intval(code, dval)

-// Enable hooks into idle and setup for HAL
-#define HAL_IDLETASK 1
-#define BOARD_INIT() HAL_init_board();
-void HAL_idletask();
-inline void HAL_init() {}
-void HAL_init_board();
+#if ENABLED(USE_ESP32_EXIO)
+  void Write_EXIO(uint8_t IO, uint8_t v);
+#endif

 //
 // Delay in cycles (used by DELAY_NS / DELAY_US)
@@ -182,3 +142,94 @@ FORCE_INLINE static void DELAY_CYCLES(uint32_t x) {
  }

 }
+
+// ------------------------
+// Class Utilities
+// ------------------------
+
+#pragma GCC diagnostic push
+#if GCC_VERSION <= 50000
+  #pragma GCC diagnostic ignored "-Wunused-function"
+#endif
+
+int freeMemory();
+
+#pragma GCC diagnostic pop
+
+void _delay_ms(const int ms);
+
+// ------------------------
+// MarlinHAL Class
+// ------------------------
+
+#define HAL_ADC_VREF         3.3
+#define HAL_ADC_RESOLUTION  10
+
+class MarlinHAL {
+public:
+
+  // Earliest possible init, before setup()
+  MarlinHAL() {}
+
+  // Watchdog
+  static void watchdog_init()    IF_DISABLED(USE_WATCHDOG, {});
+  static void watchdog_refresh() IF_DISABLED(USE_WATCHDOG, {});
+
+  static void init() {}        // Called early in setup()
+  static void init_board();    // Called less early in setup()
+  static void reboot();        // Restart the firmware
+
+  // Interrupts
+  static portMUX_TYPE spinlock;
+  static bool isr_state() { return spinlock.owner == portMUX_FREE_VAL; }
+  static void isr_on()  { if (spinlock.owner != portMUX_FREE_VAL) portEXIT_CRITICAL(&spinlock); }
+  static void isr_off() { portENTER_CRITICAL(&spinlock); }
+
+  static void delay_ms(const int ms) { _delay_ms(ms); }
+
+  // Tasks, called from idle()
+  static void idletask();
+
+  // Reset
+  static uint8_t get_reset_source();
+  static void clear_reset_source() {}
+
+  // Free SRAM
+  static int freeMemory();
+
+  //
+  // ADC Methods
+  //
+
+  static uint16_t adc_result;
+
+  // Called by Temperature::init once at startup
+  static void adc_init();
+
+  // Called by Temperature::init for each sensor at startup
+  static void adc_enable(const pin_t pin) {}
+
+  // Begin ADC sampling on the given pin. Called from Temperature::isr!
+  static void adc_start(const pin_t pin);
+
+  // Is the ADC ready for reading?
+  static bool adc_ready() { return true; }
+
+  // The current value of the ADC register
+  static uint16_t adc_value() { return adc_result; }
+
+  /**
+   * If not already allocated, allocate a hardware PWM channel
+   * to the pin and set the duty cycle..
+   * Optionally invert the duty cycle [default = false]
+   * Optionally change the scale of the provided value to enable finer PWM duty control [default = 255]
+   */
+  static void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size=255, const bool invert=false);
+
+  /**
+   * Allocate and set the frequency of a hardware PWM pin
+   * Returns -1 if no pin available.
+   */
+  static int8_t set_pwm_frequency(const pin_t pin, const uint32_t f_desired);
+
+};
@@ -53,11 +53,9 @@ static SPISettings spiConfig;
 // ------------------------

 void spiBegin() {
-  #if !PIN_EXISTS(SD_SS)
-    #error "SD_SS_PIN not defined!"
+  #if ENABLED(SDSUPPORT) && PIN_EXISTS(SD_SS)
+    OUT_WRITE(SD_SS_PIN, HIGH);
  #endif
-
-  OUT_WRITE(SD_SS_PIN, HIGH);
 }

 void spiInit(uint8_t spiRate) {
@@ -1,6 +1,6 @@
 /**
 * Marlin 3D Printer Firmware
- * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2021 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
@@ -21,5 +21,6 @@
 */
 #pragma once

-void watchdog_init();
-void HAL_watchdog_refresh();
+#include <SPI.h>
+
+using MarlinSPI = SPIClass;
@@ -31,20 +31,18 @@
 // so we only allocate servo channels up high to avoid side effects with regards to analogWrite (fans, leds, laser pwm etc.)
 int Servo::channel_next_free = 12;

-Servo::Servo() {
-  channel = channel_next_free++;
-}
+Servo::Servo() {}

 int8_t Servo::attach(const int inPin) {
-  if (channel >= CHANNEL_MAX_NUM) return -1;
  if (inPin > 0) pin = inPin;
-
-  ledcSetup(channel, 50, 16); // channel X, 50 Hz, 16-bit depth
-  ledcAttachPin(pin, channel);
-  return true;
+  channel = get_pwm_channel(pin, 50u, 16u);
+  return channel; // -1 if no PWM avail.
 }

-void Servo::detach() { ledcDetachPin(pin); }
+// leave channel connected to servo - set duty to zero
+void Servo::detach() {
+  if (channel >= 0) ledcWrite(channel, 0);
+}

 int Servo::read() { return degrees; }

@@ -52,7 +50,7 @@ void Servo::write(int inDegrees) {
  degrees = constrain(inDegrees, MIN_ANGLE, MAX_ANGLE);
  int us = map(degrees, MIN_ANGLE, MAX_ANGLE, MIN_PULSE_WIDTH, MAX_PULSE_WIDTH);
  int duty = map(us, 0, TAU_USEC, 0, MAX_COMPARE);
-  ledcWrite(channel, duty);
+  if (channel >= 0) ledcWrite(channel, duty); // don't save duty for servos!
 }

 void Servo::move(const int value) {
@@ -30,8 +30,7 @@ class Servo {
                   MAX_PULSE_WIDTH = 2400,  // Longest pulse sent to a servo
                   TAU_MSEC = 20,
                   TAU_USEC = (TAU_MSEC * 1000),
-                   MAX_COMPARE = _BV(16) - 1, // 65535
-                   CHANNEL_MAX_NUM = 16;
+                   MAX_COMPARE = _BV(16) - 1; // 65535

 public:
  Servo();
@@ -35,19 +35,19 @@
 static pin_t tone_pin;
 volatile static int32_t toggles;

-void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration) {
+void tone(const pin_t _pin, const unsigned int frequency, const unsigned long duration/*=0*/) {
  tone_pin = _pin;
  toggles = 2 * frequency * duration / 1000;
-  HAL_timer_start(TONE_TIMER_NUM, 2 * frequency);
+  HAL_timer_start(MF_TIMER_TONE, 2 * frequency);
 }

 void noTone(const pin_t _pin) {
-  HAL_timer_disable_interrupt(TONE_TIMER_NUM);
+  HAL_timer_disable_interrupt(MF_TIMER_TONE);
  WRITE(_pin, LOW);
 }

 HAL_TONE_TIMER_ISR() {
-  HAL_timer_isr_prologue(TONE_TIMER_NUM);
+  HAL_timer_isr_prologue(MF_TIMER_TONE);

  if (toggles) {
    toggles--;
@@ -65,4 +65,10 @@ void setup_endstop_interrupts() {
  TERN_(HAS_J_MIN, _ATTACH(J_MIN_PIN));
  TERN_(HAS_K_MAX, _ATTACH(K_MAX_PIN));
  TERN_(HAS_K_MIN, _ATTACH(K_MIN_PIN));
+  TERN_(HAS_U_MAX, _ATTACH(U_MAX_PIN));
+  TERN_(HAS_U_MIN, _ATTACH(U_MIN_PIN));
+  TERN_(HAS_V_MAX, _ATTACH(V_MAX_PIN));
+  TERN_(HAS_V_MIN, _ATTACH(V_MIN_PIN));
+  TERN_(HAS_W_MAX, _ATTACH(W_MAX_PIN));
+  TERN_(HAS_W_MIN, _ATTACH(W_MIN_PIN));
 }
@@ -0,0 +1,6 @@
+# Name,   Type, SubType, Offset,  Size, Flags
+nvs,      data, nvs,     0x9000,   0x5000,
+otadata,  data, ota,     0xe000,   0x2000,
+app0,     app,  ota_0,   0x10000,  0x180000,
+app1,     app,  ota_1,   0x190000, 0x180000,
+spiffs,   data, spiffs,  0x310000, 0xF0000,
@@ -40,13 +40,19 @@
 // Set pin as input with pullup mode
 #define _PULLUP(IO, v)          pinMode(IO, v ? INPUT_PULLUP : INPUT)

-// Read a pin wrapper
-#define READ(IO)                (IS_I2S_EXPANDER_PIN(IO) ? i2s_state(I2S_EXPANDER_PIN_INDEX(IO)) : digitalRead(IO))
+#if ENABLED(USE_ESP32_EXIO)
+  // Read a pin wrapper
+  #define READ(IO)                digitalRead(IO)
+  // Write to a pin wrapper
+  #define WRITE(IO, v)            (IO >= 100 ? Write_EXIO(IO, v) : digitalWrite(IO, v))
+#else
+  // Read a pin wrapper
+  #define READ(IO)                (IS_I2S_EXPANDER_PIN(IO) ? i2s_state(I2S_EXPANDER_PIN_INDEX(IO)) : digitalRead(IO))
+  // Write to a pin wrapper
+  #define WRITE(IO, v)            (IS_I2S_EXPANDER_PIN(IO) ? i2s_write(I2S_EXPANDER_PIN_INDEX(IO), v) : digitalWrite(IO, v))
+#endif

-// Write to a pin wrapper
-#define WRITE(IO, v)            (IS_I2S_EXPANDER_PIN(IO) ? i2s_write(I2S_EXPANDER_PIN_INDEX(IO), v) : digitalWrite(IO, v))
-
-// Set pin as input wrapper
+// Set pin as input wrapper (0x80 | (v << 5) | (IO - 100))
 #define SET_INPUT(IO)           _SET_INPUT(IO)

 // Set pin as input with pullup wrapper
@@ -23,6 +23,8 @@

 #include "../../inc/MarlinConfigPre.h"

+#if DISABLED(USE_ESP32_EXIO)
+
 #include "i2s.h"

 #include "../shared/Marduino.h"
@@ -62,12 +64,9 @@ uint32_t i2s_port_data = 0;
 #define I2S_EXIT_CRITICAL()   portEXIT_CRITICAL(&i2s_spinlock[i2s_num])

 static inline void gpio_matrix_out_check(uint32_t gpio, uint32_t signal_idx, bool out_inv, bool oen_inv) {
-  //if pin = -1, do not need to configure
-  if (gpio != -1) {
-    PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[gpio], PIN_FUNC_GPIO);
-    gpio_set_direction((gpio_num_t)gpio, (gpio_mode_t)GPIO_MODE_DEF_OUTPUT);
-    gpio_matrix_out(gpio, signal_idx, out_inv, oen_inv);
-  }
+  PIN_FUNC_SELECT(GPIO_PIN_MUX_REG[gpio], PIN_FUNC_GPIO);
+  gpio_set_direction((gpio_num_t)gpio, (gpio_mode_t)GPIO_MODE_DEF_OUTPUT);
+  gpio_matrix_out(gpio, signal_idx, out_inv, oen_inv);
 }

 static esp_err_t i2s_reset_fifo(i2s_port_t i2s_num) {
@@ -254,13 +253,7 @@ int i2s_init() {

  I2S0.fifo_conf.dscr_en = 0;

-  I2S0.conf_chan.tx_chan_mod = (
-    #if ENABLED(I2S_STEPPER_SPLIT_STREAM)
-      4
-    #else
-      0
-    #endif
-  );
+  I2S0.conf_chan.tx_chan_mod = TERN(I2S_STEPPER_SPLIT_STREAM, 4, 0);
  I2S0.fifo_conf.tx_fifo_mod = 0;
  I2S0.conf.tx_mono = 0;

@@ -311,9 +304,16 @@ int i2s_init() {
  xTaskCreatePinnedToCore(stepperTask, "StepperTask", 10000, nullptr, 1, nullptr, CONFIG_ARDUINO_RUNNING_CORE); // run I2S stepper task on same core as rest of Marlin

  // Route the i2s pins to the appropriate GPIO
-  gpio_matrix_out_check(I2S_DATA, I2S0O_DATA_OUT23_IDX, 0, 0);
-  gpio_matrix_out_check(I2S_BCK, I2S0O_BCK_OUT_IDX, 0, 0);
-  gpio_matrix_out_check(I2S_WS, I2S0O_WS_OUT_IDX, 0, 0);
+  // If a pin is not defined, no need to configure
+  #if defined(I2S_DATA) && I2S_DATA >= 0
+    gpio_matrix_out_check(I2S_DATA, I2S0O_DATA_OUT23_IDX, 0, 0);
+  #endif
+  #if defined(I2S_BCK) && I2S_BCK >= 0
+    gpio_matrix_out_check(I2S_BCK, I2S0O_BCK_OUT_IDX, 0, 0);
+  #endif
+  #if defined(I2S_WS) && I2S_WS >= 0
+    gpio_matrix_out_check(I2S_WS, I2S0O_WS_OUT_IDX, 0, 0);
+  #endif

  // Start the I2S peripheral
  return i2s_start(I2S_NUM_0);
@@ -340,4 +340,5 @@ void i2s_push_sample() {
  dma.current[dma.rw_pos++] = i2s_port_data;
 }

+#endif // !USE_ESP32_EXIO
 #endif // ARDUINO_ARCH_ESP32
@@ -25,8 +25,8 @@
  #error "EMERGENCY_PARSER is not yet implemented for ESP32. Disable EMERGENCY_PARSER to continue."
 #endif

-#if ENABLED(FAST_PWM_FAN) || SPINDLE_LASER_FREQUENCY
-  #error "Features requiring Hardware PWM (FAST_PWM_FAN, SPINDLE_LASER_FREQUENCY) are not yet supported on ESP32."
+#if (ENABLED(SPINDLE_LASER_USE_PWM) && SPINDLE_LASER_FREQUENCY > 78125) || (ENABLED(FAST_PWM_FAN_FREQUENCY) && FAST_PWM_FAN_FREQUENCY > 78125)
+  #error "SPINDLE_LASER_FREQUENCY and FAST_PWM_FREQUENCY maximum value is 78125Hz for ESP32."
 #endif

 #if HAS_TMC_SW_SERIAL
@@ -40,3 +40,11 @@
 #if ENABLED(POSTMORTEM_DEBUGGING)
  #error "POSTMORTEM_DEBUGGING is not yet supported on ESP32."
 #endif
+
+#if MB(MKS_TINYBEE) && ENABLED(FAST_PWM_FAN)
+  #error "FAST_PWM_FAN is not available on TinyBee."
+#endif
+
+#if USING_PULLDOWNS
+  #error "PULLDOWN pin mode is not available on ESP32 boards."
+#endif
@@ -2,6 +2,9 @@
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
@@ -41,7 +41,7 @@

 static timg_dev_t *TG[2] = {&TIMERG0, &TIMERG1};

-const tTimerConfig TimerConfig [NUM_HARDWARE_TIMERS] = {
+const tTimerConfig timer_config[NUM_HARDWARE_TIMERS] = {
  { TIMER_GROUP_0, TIMER_0, STEPPER_TIMER_PRESCALE, stepTC_Handler }, // 0 - Stepper
  { TIMER_GROUP_0, TIMER_1,    TEMP_TIMER_PRESCALE, tempTC_Handler }, // 1 - Temperature
  { TIMER_GROUP_1, TIMER_0,     PWM_TIMER_PRESCALE, pwmTC_Handler  }, // 2 - PWM
@@ -53,7 +53,7 @@ const tTimerConfig TimerConfig [NUM_HARDWARE_TIMERS] = {
 // ------------------------

 void IRAM_ATTR timer_isr(void *para) {
-  const tTimerConfig& timer = TimerConfig[(int)para];
+  const tTimerConfig& timer = timer_config[(int)para];

  // Retrieve the interrupt status and the counter value
  // from the timer that reported the interrupt
@@ -81,8 +81,8 @@ void IRAM_ATTR timer_isr(void *para) {
 * @param timer_num timer number to initialize
 * @param frequency frequency of the timer
 */
-void HAL_timer_start(const uint8_t timer_num, uint32_t frequency) {
-  const tTimerConfig timer = TimerConfig[timer_num];
+void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency) {
+  const tTimerConfig timer = timer_config[timer_num];

  timer_config_t config;
  config.divider     = timer.divider;
@@ -115,7 +115,7 @@ void HAL_timer_start(const uint8_t timer_num, uint32_t frequency) {
 * @param count     threshold at which the interrupt is triggered
 */
 void HAL_timer_set_compare(const uint8_t timer_num, hal_timer_t count) {
-  const tTimerConfig timer = TimerConfig[timer_num];
+  const tTimerConfig timer = timer_config[timer_num];
  timer_set_alarm_value(timer.group, timer.idx, count);
 }

@@ -125,7 +125,7 @@ void HAL_timer_set_compare(const uint8_t timer_num, hal_timer_t count) {
 * @return           the timer current threshold for the alarm to be triggered
 */
 hal_timer_t HAL_timer_get_compare(const uint8_t timer_num) {
-  const tTimerConfig timer = TimerConfig[timer_num];
+  const tTimerConfig timer = timer_config[timer_num];

  uint64_t alarm_value;
  timer_get_alarm_value(timer.group, timer.idx, &alarm_value);
@@ -139,7 +139,7 @@ hal_timer_t HAL_timer_get_compare(const uint8_t timer_num) {
 * @return           the current counter of the alarm
 */
 hal_timer_t HAL_timer_get_count(const uint8_t timer_num) {
-  const tTimerConfig timer = TimerConfig[timer_num];
+  const tTimerConfig timer = timer_config[timer_num];
  uint64_t counter_value;
  timer_get_counter_value(timer.group, timer.idx, &counter_value);
  return counter_value;
@@ -150,7 +150,7 @@ hal_timer_t HAL_timer_get_count(const uint8_t timer_num) {
 * @param timer_num timer number to enable interrupts on
 */
 void HAL_timer_enable_interrupt(const uint8_t timer_num) {
-  //const tTimerConfig timer = TimerConfig[timer_num];
+  //const tTimerConfig timer = timer_config[timer_num];
  //timer_enable_intr(timer.group, timer.idx);
 }

@@ -159,12 +159,12 @@ void HAL_timer_enable_interrupt(const uint8_t timer_num) {
 * @param timer_num timer number to disable interrupts on
 */
 void HAL_timer_disable_interrupt(const uint8_t timer_num) {
-  //const tTimerConfig timer = TimerConfig[timer_num];
+  //const tTimerConfig timer = timer_config[timer_num];
  //timer_disable_intr(timer.group, timer.idx);
 }

 bool HAL_timer_interrupt_enabled(const uint8_t timer_num) {
-  const tTimerConfig timer = TimerConfig[timer_num];
+  const tTimerConfig timer = timer_config[timer_num];
  return TG[timer.group]->int_ena.val | BIT(timer_num);
 }

@@ -32,20 +32,20 @@
 typedef uint64_t hal_timer_t;
 #define HAL_TIMER_TYPE_MAX 0xFFFFFFFFFFFFFFFFULL

-#ifndef STEP_TIMER_NUM
-  #define STEP_TIMER_NUM        0  // Timer Index for Stepper
+#ifndef MF_TIMER_STEP
+  #define MF_TIMER_STEP         0  // Timer Index for Stepper
 #endif
-#ifndef PULSE_TIMER_NUM
-  #define PULSE_TIMER_NUM       STEP_TIMER_NUM
+#ifndef MF_TIMER_PULSE
+  #define MF_TIMER_PULSE        MF_TIMER_STEP
 #endif
-#ifndef TEMP_TIMER_NUM
-  #define TEMP_TIMER_NUM        1  // Timer Index for Temperature
+#ifndef MF_TIMER_TEMP
+  #define MF_TIMER_TEMP         1  // Timer Index for Temperature
 #endif
-#ifndef PWM_TIMER_NUM
-  #define PWM_TIMER_NUM         2  // index of timer to use for PWM outputs
+#ifndef MF_TIMER_PWM
+  #define MF_TIMER_PWM          2  // index of timer to use for PWM outputs
 #endif
-#ifndef TONE_TIMER_NUM
-  #define TONE_TIMER_NUM        3  // index of timer for beeper tones
+#ifndef MF_TIMER_TONE
+  #define MF_TIMER_TONE         3  // index of timer for beeper tones
 #endif

 #define HAL_TIMER_RATE APB_CLK_FREQ // frequency of timer peripherals
@@ -79,12 +79,12 @@ typedef uint64_t hal_timer_t;
 #define PULSE_TIMER_PRESCALE     STEPPER_TIMER_PRESCALE
 #define PULSE_TIMER_TICKS_PER_US STEPPER_TIMER_TICKS_PER_US

-#define ENABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_enable_interrupt(STEP_TIMER_NUM)
-#define DISABLE_STEPPER_DRIVER_INTERRUPT()  HAL_timer_disable_interrupt(STEP_TIMER_NUM)
-#define STEPPER_ISR_ENABLED() HAL_timer_interrupt_enabled(STEP_TIMER_NUM)
+#define ENABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_enable_interrupt(MF_TIMER_STEP)
+#define DISABLE_STEPPER_DRIVER_INTERRUPT()  HAL_timer_disable_interrupt(MF_TIMER_STEP)
+#define STEPPER_ISR_ENABLED() HAL_timer_interrupt_enabled(MF_TIMER_STEP)

-#define ENABLE_TEMPERATURE_INTERRUPT()  HAL_timer_enable_interrupt(TEMP_TIMER_NUM)
-#define DISABLE_TEMPERATURE_INTERRUPT() HAL_timer_disable_interrupt(TEMP_TIMER_NUM)
+#define ENABLE_TEMPERATURE_INTERRUPT()  HAL_timer_enable_interrupt(MF_TIMER_TEMP)
+#define DISABLE_TEMPERATURE_INTERRUPT() HAL_timer_disable_interrupt(MF_TIMER_TEMP)

 #ifndef HAL_TEMP_TIMER_ISR
  #define HAL_TEMP_TIMER_ISR() extern "C" void tempTC_Handler()
@@ -121,13 +121,13 @@ typedef struct {
 // Public Variables
 // ------------------------

-extern const tTimerConfig TimerConfig[];
+extern const tTimerConfig timer_config[];

 // ------------------------
 // Public functions
 // ------------------------

-void HAL_timer_start (const uint8_t timer_num, uint32_t frequency);
+void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency);
 void HAL_timer_set_compare(const uint8_t timer_num, const hal_timer_t count);
 hal_timer_t HAL_timer_get_compare(const uint8_t timer_num);
 hal_timer_t HAL_timer_get_count(const uint8_t timer_num);
@@ -136,5 +136,5 @@ void HAL_timer_enable_interrupt(const uint8_t timer_num);
 void HAL_timer_disable_interrupt(const uint8_t timer_num);
 bool HAL_timer_interrupt_enabled(const uint8_t timer_num);

-#define HAL_timer_isr_prologue(TIMER_NUM)
-#define HAL_timer_isr_epilogue(TIMER_NUM)
+#define HAL_timer_isr_prologue(T) NOOP
+#define HAL_timer_isr_epilogue(T) NOOP
@@ -0,0 +1,94 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2022 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * Copypaste of SAMD51 HAL developed by Giuliano Zaro (AKA GMagician)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#ifdef ARDUINO_ARCH_ESP32
+
+#include "../../inc/MarlinConfig.h"
+
+#if EITHER(MKS_MINI_12864, FYSETC_MINI_12864_2_1)
+
+#include <U8glib-HAL.h>
+#include "../shared/HAL_SPI.h"
+#include "HAL.h"
+#include "SPI.h"
+
+static SPISettings spiConfig;
+
+
+#ifndef LCD_SPI_SPEED
+  #ifdef SD_SPI_SPEED
+    #define LCD_SPI_SPEED SD_SPI_SPEED    // Assume SPI speed shared with SD
+  #else
+    #define LCD_SPI_SPEED SPI_FULL_SPEED  // Use full speed if SD speed is not supplied
+  #endif
+#endif
+
+uint8_t u8g_eps_hw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr) {
+  static uint8_t msgInitCount = 2; // Ignore all messages until 2nd U8G_COM_MSG_INIT
+  if (msgInitCount) {
+    if (msg == U8G_COM_MSG_INIT) msgInitCount--;
+    if (msgInitCount) return -1;
+  }
+
+  switch (msg) {
+    case U8G_COM_MSG_STOP: break;
+
+    case U8G_COM_MSG_INIT:
+      OUT_WRITE(DOGLCD_CS, HIGH);
+      OUT_WRITE(DOGLCD_A0, HIGH);
+      OUT_WRITE(LCD_RESET_PIN, HIGH);
+      u8g_Delay(5);
+      spiBegin();
+      spiInit(LCD_SPI_SPEED);
+      break;
+
+    case U8G_COM_MSG_ADDRESS:           /* define cmd (arg_val = 0) or data mode (arg_val = 1) */
+      WRITE(DOGLCD_A0, arg_val ? HIGH : LOW);
+      break;
+
+    case U8G_COM_MSG_CHIP_SELECT:       /* arg_val == 0 means HIGH level of U8G_PI_CS */
+      WRITE(DOGLCD_CS, arg_val ? LOW : HIGH);
+      break;
+
+    case U8G_COM_MSG_RESET:
+      WRITE(LCD_RESET_PIN, arg_val);
+      break;
+
+    case U8G_COM_MSG_WRITE_BYTE:
+      spiSend((uint8_t)arg_val);
+      break;
+
+    case U8G_COM_MSG_WRITE_SEQ:
+      uint8_t *ptr = (uint8_t*) arg_ptr;
+      while (arg_val > 0) {
+        spiSend(*ptr++);
+        arg_val--;
+      }
+      break;
+  }
+  return 1;
+}
+
+#endif // EITHER(MKS_MINI_12864, FYSETC_MINI_12864_2_1)
+
+#endif // ARDUINO_ARCH_ESP32
@@ -59,7 +59,7 @@ void wifi_init() {

  MDNS.addService("http", "tcp", 80);

-  SERIAL_ECHOLNPAIR("Successfully connected to WiFi with SSID '" WIFI_SSID "', hostname: '" WIFI_HOSTNAME "', IP address: ", WiFi.localIP().toString().c_str());
+  SERIAL_ECHOLNPGM("Successfully connected to WiFi with SSID '" WIFI_SSID "', hostname: '" WIFI_HOSTNAME "', IP address: ", WiFi.localIP().toString().c_str());
 }

 #endif // WIFISUPPORT
@@ -28,6 +28,7 @@
 #endif

 #include HAL_PATH(.,HAL.h)
+extern MarlinHAL hal;

 #define HAL_ADC_RANGE _BV(HAL_ADC_RESOLUTION)

@@ -44,7 +45,3 @@
 #ifndef PGMSTR
  #define PGMSTR(NAM,STR) const char NAM[] = STR
 #endif
-
-inline void watchdog_refresh() {
-  TERN_(USE_WATCHDOG, HAL_watchdog_refresh());
-}
@@ -24,6 +24,10 @@
 #include "../../inc/MarlinConfig.h"
 #include "../shared/Delay.h"

+// ------------------------
+// Serial ports
+// ------------------------
+
 MSerialT usb_serial(TERN0(EMERGENCY_PARSER, true));

 // U8glib required functions
@@ -37,42 +41,21 @@ extern "C" {
 //************************//

 // return free heap space
-int freeMemory() {
-  return 0;
-}
+int freeMemory() { return 0; }

 // ------------------------
 // ADC
 // ------------------------

-void HAL_adc_init() {
+uint8_t MarlinHAL::active_ch = 0;

-}
-
-void HAL_adc_enable_channel(const uint8_t ch) {
-
-}
-
-uint8_t active_ch = 0;
-void HAL_adc_start_conversion(const uint8_t ch) {
-  active_ch = ch;
-}
-
-bool HAL_adc_finished() {
-  return true;
-}
-
-uint16_t HAL_adc_get_result() {
-  pin_t pin = analogInputToDigitalPin(active_ch);
+uint16_t MarlinHAL::adc_value() {
+  const pin_t pin = analogInputToDigitalPin(active_ch);
  if (!VALID_PIN(pin)) return 0;
-  uint16_t data = ((Gpio::get(pin) >> 2) & 0x3FF);
+  const uint16_t data = ((Gpio::get(pin) >> 2) & 0x3FF);
  return data;    // return 10bit value as Marlin expects
 }

-void HAL_pwm_init() {
-
-}
-
-void HAL_reboot() { /* Reset the application state and GPIO */ }
+void MarlinHAL::reboot() { /* Reset the application state and GPIO */ }

 #endif // __PLAT_LINUX__
@@ -21,25 +21,42 @@
 */
 #pragma once

-#define CPU_32_BIT
+#include "../../inc/MarlinConfigPre.h"

-#define F_CPU 100000000UL
-#define SystemCoreClock F_CPU
 #include <iostream>
 #include <stdint.h>
 #include <stdarg.h>
-
 #undef min
 #undef max
-
 #include <algorithm>

-void _printf (const  char *format, ...);
+#include "hardware/Clock.h"
+#include "../shared/Marduino.h"
+#include "../shared/math_32bit.h"
+#include "../shared/HAL_SPI.h"
+#include "fastio.h"
+#include "serial.h"
+
+// ------------------------
+// Defines
+// ------------------------
+
+#define CPU_32_BIT
+#define SHARED_SERVOS HAS_SERVOS  // Use shared/servos.cpp
+
+#define F_CPU 100000000UL
+#define SystemCoreClock F_CPU
+
+#define DELAY_CYCLES(x) Clock::delayCycles(x)
+
+#define CPU_ST7920_DELAY_1 600
+#define CPU_ST7920_DELAY_2 750
+#define CPU_ST7920_DELAY_3 750
+
+void _printf(const  char *format, ...);
 void _putc(uint8_t c);
 uint8_t _getc();

-//extern "C" volatile uint32_t _millis;
-
 //arduino: Print.h
 #define DEC 10
 #define HEX 16
@@ -49,67 +66,100 @@ uint8_t _getc();
 #define B01 1
 #define B10 2

-#include "hardware/Clock.h"
-
-#include "../shared/Marduino.h"
-#include "../shared/math_32bit.h"
-#include "../shared/HAL_SPI.h"
-#include "fastio.h"
-#include "watchdog.h"
-#include "serial.h"
-
-#define SHARED_SERVOS HAS_SERVOS
+// ------------------------
+// Serial ports
+// ------------------------

 extern MSerialT usb_serial;
 #define MYSERIAL1 usb_serial

-#define ST7920_DELAY_1 DELAY_NS(600)
-#define ST7920_DELAY_2 DELAY_NS(750)
-#define ST7920_DELAY_3 DELAY_NS(750)
-
 //
 // Interrupts
 //
 #define CRITICAL_SECTION_START()
 #define CRITICAL_SECTION_END()
-#define ISRS_ENABLED()
-#define ENABLE_ISRS()
-#define DISABLE_ISRS()

-inline void HAL_init() {}
+// ADC
+#define HAL_ADC_VREF           5.0
+#define HAL_ADC_RESOLUTION    10

-// Utility functions
+// ------------------------
+// Class Utilities
+// ------------------------
+
+#pragma GCC diagnostic push
 #if GCC_VERSION <= 50000
-  #pragma GCC diagnostic push
  #pragma GCC diagnostic ignored "-Wunused-function"
 #endif

 int freeMemory();

-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic pop
-#endif
+#pragma GCC diagnostic pop

-// ADC
-#define HAL_ADC_VREF           5.0
-#define HAL_ADC_RESOLUTION    10
-#define HAL_ANALOG_SELECT(ch) HAL_adc_enable_channel(ch)
-#define HAL_START_ADC(ch)     HAL_adc_start_conversion(ch)
-#define HAL_READ_ADC()        HAL_adc_get_result()
-#define HAL_ADC_READY()       true
+// ------------------------
+// MarlinHAL Class
+// ------------------------

-void HAL_adc_init();
-void HAL_adc_enable_channel(const uint8_t ch);
-void HAL_adc_start_conversion(const uint8_t ch);
-uint16_t HAL_adc_get_result();
+class MarlinHAL {
+public:

-// Reset source
-inline void HAL_clear_reset_source(void) {}
-inline uint8_t HAL_get_reset_source(void) { return RST_POWER_ON; }
+  // Earliest possible init, before setup()
+  MarlinHAL() {}

-void HAL_reboot(); // Reset the application state and GPIO
+  // Watchdog
+  static void watchdog_init() {}
+  static void watchdog_refresh() {}

-/* ---------------- Delay in cycles */
-FORCE_INLINE static void DELAY_CYCLES(uint64_t x) {
-  Clock::delayCycles(x);
-}
+  static void init() {}        // Called early in setup()
+  static void init_board() {}  // Called less early in setup()
+  static void reboot();        // Reset the application state and GPIO
+
+  // Interrupts
+  static bool isr_state() { return true; }
+  static void isr_on()  {}
+  static void isr_off() {}
+
+  static void delay_ms(const int ms) { _delay_ms(ms); }
+
+  // Tasks, called from idle()
+  static void idletask() {}
+
+  // Reset
+  static constexpr uint8_t reset_reason = RST_POWER_ON;
+  static uint8_t get_reset_source() { return reset_reason; }
+  static void clear_reset_source() {}
+
+  // Free SRAM
+  static int freeMemory() { return ::freeMemory(); }
+
+  //
+  // ADC Methods
+  //
+
+  static uint8_t active_ch;
+
+  // Called by Temperature::init once at startup
+  static void adc_init() {}
+
+  // Called by Temperature::init for each sensor at startup
+  static void adc_enable(const uint8_t) {}
+
+  // Begin ADC sampling on the given channel
+  static void adc_start(const uint8_t ch) { active_ch = ch; }
+
+  // Is the ADC ready for reading?
+  static bool adc_ready() { return true; }
+
+  // The current value of the ADC register
+  static uint16_t adc_value();
+
+  /**
+   * Set the PWM duty cycle for the pin to the given value.
+   * No option to change the resolution or invert the duty cycle.
+   */
+  static void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t=255, const bool=false) {
+    analogWrite(pin, v);
+  }
+
+  static void set_pwm_frequency(const pin_t, int) {}
+};
@@ -1,6 +1,6 @@
 /**
 * Marlin 3D Printer Firmware
- * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2021 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
 * Based on Sprinter and grbl.
 * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
@@ -21,8 +21,6 @@
 */
 #pragma once

-void watchdog_init();
-void HAL_watchdog_refresh();
+#include <SPI.h>

-bool watchdog_timed_out();
-void watchdog_clear_timeout_flag();
+using MarlinSPI = SPIClass;
@@ -31,9 +31,7 @@ void cli() { } // Disable
 void sei() { } // Enable

 // Time functions
-void _delay_ms(const int delay_ms) {
-  delay(delay_ms);
-}
+void _delay_ms(const int ms) { delay(ms); }

 uint32_t millis() {
  return (uint32_t)Clock::millis();
@@ -26,7 +26,7 @@
 */

 // Emulating RAMPS
-#if ENABLED(SPINDLE_LASER_PWM) && !(SPINDLE_LASER_PWM_PIN == 4 || SPINDLE_LASER_PWM_PIN == 6 || SPINDLE_LASER_PWM_PIN == 11)
+#if ENABLED(SPINDLE_LASER_USE_PWM) && !(SPINDLE_LASER_PWM_PIN == 4 || SPINDLE_LASER_PWM_PIN == 6 || SPINDLE_LASER_PWM_PIN == 11)
  #error "SPINDLE_LASER_PWM_PIN must use SERVO0, SERVO1 or SERVO3 connector"
 #endif

@@ -59,10 +59,9 @@ typedef uint8_t byte;
 #endif

 #define sq(v) ((v) * (v))
-#define square(v) sq(v)
 #define constrain(value, arg_min, arg_max) ((value) < (arg_min) ? (arg_min) :((value) > (arg_max) ? (arg_max) : (value)))

-//Interrupts
+// Interrupts
 void cli(); // Disable
 void sei(); // Enable
 void attachInterrupt(uint32_t pin, void (*callback)(), uint32_t mode);
@@ -74,8 +73,8 @@ extern "C" {
 }

 // Time functions
-extern "C" void delay(const int milis);
-void _delay_ms(const int delay);
+extern "C" void delay(const int ms);
+void _delay_ms(const int ms);
 void delayMicroseconds(unsigned long);
 uint32_t millis();

@@ -2,6 +2,9 @@
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
@@ -16,6 +19,7 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 *
 */
+
 #ifdef __PLAT_LINUX__

 //#define GPIO_LOGGING // Full GPIO and Positional Logging
@@ -2,6 +2,9 @@
 * Marlin 3D Printer Firmware
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
 *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
@@ -34,6 +37,7 @@
 #define GET_ARRAY_PIN(p)    pin_array[p].pin
 #define PRINT_ARRAY_NAME(x) do{ sprintf_P(buffer, PSTR("%-" STRINGIFY(MAX_NAME_LENGTH) "s"), pin_array[x].name); SERIAL_ECHO(buffer); }while(0)
 #define PRINT_PIN(p)        do{ sprintf_P(buffer, PSTR("%3d "), p); SERIAL_ECHO(buffer); }while(0)
+#define PRINT_PIN_ANALOG(p) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), DIGITAL_PIN_TO_ANALOG_PIN(pin)); SERIAL_ECHO(buffer); }while(0)
 #define MULTI_NAME_PAD  16 // space needed to be pretty if not first name assigned to a pin

 // active ADC function/mode/code values for PINSEL registers
@@ -37,14 +37,14 @@ typedef uint32_t hal_timer_t;

 #define HAL_TIMER_RATE         ((SystemCoreClock) / 4)  // frequency of timers peripherals

-#ifndef STEP_TIMER_NUM
-  #define STEP_TIMER_NUM        0  // Timer Index for Stepper
+#ifndef MF_TIMER_STEP
+  #define MF_TIMER_STEP         0  // Timer Index for Stepper
 #endif
-#ifndef PULSE_TIMER_NUM
-  #define PULSE_TIMER_NUM       STEP_TIMER_NUM
+#ifndef MF_TIMER_PULSE
+  #define MF_TIMER_PULSE        MF_TIMER_STEP
 #endif
-#ifndef TEMP_TIMER_NUM
-  #define TEMP_TIMER_NUM        1  // Timer Index for Temperature
+#ifndef MF_TIMER_TEMP
+  #define MF_TIMER_TEMP         1  // Timer Index for Temperature
 #endif

 #define TEMP_TIMER_RATE        1000000
@@ -58,12 +58,12 @@ typedef uint32_t hal_timer_t;
 #define PULSE_TIMER_PRESCALE   STEPPER_TIMER_PRESCALE
 #define PULSE_TIMER_TICKS_PER_US STEPPER_TIMER_TICKS_PER_US

-#define ENABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_enable_interrupt(STEP_TIMER_NUM)
-#define DISABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_disable_interrupt(STEP_TIMER_NUM)
-#define STEPPER_ISR_ENABLED() HAL_timer_interrupt_enabled(STEP_TIMER_NUM)
+#define ENABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_enable_interrupt(MF_TIMER_STEP)
+#define DISABLE_STEPPER_DRIVER_INTERRUPT() HAL_timer_disable_interrupt(MF_TIMER_STEP)
+#define STEPPER_ISR_ENABLED() HAL_timer_interrupt_enabled(MF_TIMER_STEP)

-#define ENABLE_TEMPERATURE_INTERRUPT() HAL_timer_enable_interrupt(TEMP_TIMER_NUM)
-#define DISABLE_TEMPERATURE_INTERRUPT() HAL_timer_disable_interrupt(TEMP_TIMER_NUM)
+#define ENABLE_TEMPERATURE_INTERRUPT() HAL_timer_enable_interrupt(MF_TIMER_TEMP)
+#define DISABLE_TEMPERATURE_INTERRUPT() HAL_timer_disable_interrupt(MF_TIMER_TEMP)

 #ifndef HAL_STEP_TIMER_ISR
  #define HAL_STEP_TIMER_ISR()  extern "C" void TIMER0_IRQHandler()
@@ -77,7 +77,6 @@ typedef uint32_t hal_timer_t;
 #define HAL_PWM_TIMER_ISR()   extern "C" void TIMER3_IRQHandler()
 #define HAL_PWM_TIMER_IRQn

-
 void HAL_timer_init();
 void HAL_timer_start(const uint8_t timer_num, const uint32_t frequency);

@@ -93,5 +92,5 @@ void HAL_timer_enable_interrupt(const uint8_t timer_num);
 void HAL_timer_disable_interrupt(const uint8_t timer_num);
 bool HAL_timer_interrupt_enabled(const uint8_t timer_num);

-#define HAL_timer_isr_prologue(TIMER_NUM)
-#define HAL_timer_isr_epilogue(TIMER_NUM)
+#define HAL_timer_isr_prologue(T) NOOP
+#define HAL_timer_isr_epilogue(T) NOOP
@@ -1,37 +0,0 @@
-/**
- * Marlin 3D Printer Firmware
- * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
- *
- * Based on Sprinter and grbl.
- * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- *
- */
-#ifdef __PLAT_LINUX__
-
-#include "../../inc/MarlinConfig.h"
-
-#if ENABLED(USE_WATCHDOG)
-
-#include "watchdog.h"
-
-#define WDT_TIMEOUT_US TERN(WATCHDOG_DURATION_8S, 8000000, 4000000) // 4 or 8 second timeout
-
-void watchdog_init() {}
-void HAL_watchdog_refresh() {}
-
-#endif
-
-#endif // __PLAT_LINUX__
@@ -25,13 +25,9 @@
 #include "../shared/Delay.h"
 #include "../../../gcode/parser.h"

-#if ENABLED(USE_WATCHDOG)
-  #include "watchdog.h"
-#endif
-
 DefaultSerial1 USBSerial(false, UsbSerial);

-uint32_t HAL_adc_reading = 0;
+uint32_t MarlinHAL::adc_result = 0;

 // U8glib required functions
 extern "C" {
@@ -41,8 +37,6 @@ extern "C" {
  void u8g_Delay(uint16_t val)       { delay(val); }
 }

-//************************//
-
 // return free heap space
 int freeMemory() {
  char stack_end;
@@ -54,7 +48,71 @@ int freeMemory() {
  return result;
 }

-// scan command line for code
+void MarlinHAL::reboot() { NVIC_SystemReset(); }
+
+uint8_t MarlinHAL::get_reset_source() {
+  #if ENABLED(USE_WATCHDOG)
+    if (watchdog_timed_out()) return RST_WATCHDOG;
+  #endif
+  return RST_POWER_ON;
+}
+
+void MarlinHAL::clear_reset_source() { watchdog_clear_timeout_flag(); }
+
+void flashFirmware(const int16_t) {
+  delay(500);          // Give OS time to disconnect
+  USB_Connect(false);  // USB clear connection
+  delay(1000);         // Give OS time to notice
+  hal.reboot();
+}
+
+#if ENABLED(USE_WATCHDOG)
+
+  #include <lpc17xx_wdt.h>
+
+  #define WDT_TIMEOUT_US TERN(WATCHDOG_DURATION_8S, 8000000, 4000000) // 4 or 8 second timeout
+
+  void MarlinHAL::watchdog_init() {
+    #if ENABLED(WATCHDOG_RESET_MANUAL)
+      // We enable the watchdog timer, but only for the interrupt.
+
+      // Configure WDT to only trigger an interrupt
+      // Disable WDT interrupt (just in case, to avoid triggering it!)
+      NVIC_DisableIRQ(WDT_IRQn);
+
+      // We NEED memory barriers to ensure Interrupts are actually disabled!
+      // ( https://dzone.com/articles/nvic-disabling-interrupts-on-arm-cortex-m-and-the )
+      __DSB();
+      __ISB();
+
+      // Configure WDT to only trigger an interrupt
+      // Initialize WDT with the given parameters
+      WDT_Init(WDT_CLKSRC_IRC, WDT_MODE_INT_ONLY);
+
+      // Configure and enable WDT interrupt.
+      NVIC_ClearPendingIRQ(WDT_IRQn);
+      NVIC_SetPriority(WDT_IRQn, 0); // Use highest priority, so we detect all kinds of lockups
+      NVIC_EnableIRQ(WDT_IRQn);
+    #else
+      WDT_Init(WDT_CLKSRC_IRC, WDT_MODE_RESET);
+    #endif
+    WDT_Start(WDT_TIMEOUT_US);
+  }
+
+  void MarlinHAL::watchdog_refresh() {
+    WDT_Feed();
+    #if DISABLED(PINS_DEBUGGING) && PIN_EXISTS(LED)
+      TOGGLE(LED_PIN);  // heartbeat indicator
+    #endif
+  }
+
+  // Timeout state
+  bool MarlinHAL::watchdog_timed_out() { return TEST(WDT_ReadTimeOutFlag(), 0); }
+  void MarlinHAL::watchdog_clear_timeout_flag() { WDT_ClrTimeOutFlag(); }
+
+#endif // USE_WATCHDOG
+
+// For M42/M43, scan command line for pin code
 //   return index into pin map array if found and the pin is valid.
 //   return dval if not found or not a valid pin.
 int16_t PARSED_PIN_INDEX(const char code, const int16_t dval) {
@@ -63,24 +121,4 @@ int16_t PARSED_PIN_INDEX(const char code, const int16_t dval) {
  return ind > -1 ? ind : dval;
 }

-void flashFirmware(const int16_t) {
-  delay(500);          // Give OS time to disconnect
-  USB_Connect(false);  // USB clear connection
-  delay(1000);         // Give OS time to notice
-  HAL_reboot();
-}
-
-void HAL_clear_reset_source(void) {
-  TERN_(USE_WATCHDOG, watchdog_clear_timeout_flag());
-}
-
-uint8_t HAL_get_reset_source(void) {
-  #if ENABLED(USE_WATCHDOG)
-    if (watchdog_timed_out()) return RST_WATCHDOG;
-  #endif
-  return RST_POWER_ON;
-}
-
-void HAL_reboot() { NVIC_SystemReset(); }
-
 #endif // TARGET_LPC1768
@@ -28,8 +28,6 @@

 #define CPU_32_BIT

-void HAL_init();
-
 #include <stdint.h>
 #include <stdarg.h>
 #include <algorithm>
@@ -40,25 +38,15 @@ extern "C" volatile uint32_t _millis;
 #include "../shared/math_32bit.h"
 #include "../shared/HAL_SPI.h"
 #include "fastio.h"
-#include "watchdog.h"
 #include "MarlinSerial.h"

 #include <adc.h>
 #include <pinmapping.h>
 #include <CDCSerial.h>

-//
-// Default graphical display delays
-//
-#ifndef ST7920_DELAY_1
-  #define ST7920_DELAY_1 DELAY_NS(600)
-#endif
-#ifndef ST7920_DELAY_2
-  #define ST7920_DELAY_2 DELAY_NS(750)
-#endif
-#ifndef ST7920_DELAY_3
-  #define ST7920_DELAY_3 DELAY_NS(750)
-#endif
+// ------------------------
+// Serial ports
+// ------------------------

 typedef ForwardSerial1Class< decltype(UsbSerial) > DefaultSerial1;
 extern DefaultSerial1 USBSerial;
@@ -113,35 +101,19 @@ extern DefaultSerial1 USBSerial;
    #error "LCD_SERIAL_PORT must be from 0 to 3. You can also use -1 if the board supports Native USB."
  #endif
  #if HAS_DGUS_LCD
-    #define SERIAL_GET_TX_BUFFER_FREE() MSerial0.available()
+    #define SERIAL_GET_TX_BUFFER_FREE() LCD_SERIAL.available()
  #endif
 #endif

 //
 // Interrupts
 //
-#define CRITICAL_SECTION_START()  uint32_t primask = __get_PRIMASK(); __disable_irq()
-#define CRITICAL_SECTION_END()    if (!primask) __enable_irq()
-#define ISRS_ENABLED() (!__get_PRIMASK())
-#define ENABLE_ISRS()  __enable_irq()
-#define DISABLE_ISRS() __disable_irq()
+
+#define CRITICAL_SECTION_START()  const bool irqon = !__get_PRIMASK(); __disable_irq()
+#define CRITICAL_SECTION_END()    if (irqon) __enable_irq()

 //
-// Utility functions
-//
-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic push
-  #pragma GCC diagnostic ignored "-Wunused-function"
-#endif
-
-int freeMemory();
-
-#if GCC_VERSION <= 50000
-  #pragma GCC diagnostic pop
-#endif
-
-//
-// ADC API
+// ADC
 //

 #define ADC_MEDIAN_FILTER_SIZE (23) // Higher values increase step delay (phase shift),
@@ -160,20 +132,9 @@ int freeMemory();
 #define HAL_ADC_RESOLUTION     12   // 15 bit maximum, raw temperature is stored as int16_t
 #define HAL_ADC_FILTERED            // Disable oversampling done in Marlin as ADC values already filtered in HAL

-using FilteredADC = LPC176x::ADC<ADC_LOWPASS_K_VALUE, ADC_MEDIAN_FILTER_SIZE>;
-extern uint32_t HAL_adc_reading;
-[[gnu::always_inline]] inline void HAL_start_adc(const pin_t pin) {
-  HAL_adc_reading = FilteredADC::read(pin) >> (16 - HAL_ADC_RESOLUTION); // returns 16bit value, reduce to required bits
-}
-[[gnu::always_inline]] inline uint16_t HAL_read_adc() {
-  return HAL_adc_reading;
-}
-
-#define HAL_adc_init()
-#define HAL_ANALOG_SELECT(pin) FilteredADC::enable_channel(pin)
-#define HAL_START_ADC(pin)     HAL_start_adc(pin)
-#define HAL_READ_ADC()         HAL_read_adc()
-#define HAL_ADC_READY()        (true)
+//
+// Pin Mapping for M42, M43, M226
+//

 // Test whether the pin is valid
 constexpr bool VALID_PIN(const pin_t pin) {
@@ -200,32 +161,107 @@ int16_t PARSED_PIN_INDEX(const char code, const int16_t dval);
 // P0.6 thru P0.9 are for the onboard SD card
 #define HAL_SENSITIVE_PINS P0_06, P0_07, P0_08, P0_09,

-#define HAL_IDLETASK 1
-void HAL_idletask();
+// ------------------------
+// Defines
+// ------------------------

 #define PLATFORM_M997_SUPPORT
 void flashFirmware(const int16_t);

 #define HAL_CAN_SET_PWM_FREQ   // This HAL supports PWM Frequency adjustment

-/**
- * set_pwm_frequency
- *  Set the frequency of the timer corresponding to the provided pin
- *  All Hardware PWM pins run at the same frequency and all
- *  Software PWM pins run at the same frequency
- */
-void set_pwm_frequency(const pin_t pin, int f_desired);
+// Default graphical display delays
+#define CPU_ST7920_DELAY_1 600
+#define CPU_ST7920_DELAY_2 750
+#define CPU_ST7920_DELAY_3 750

-/**
- * set_pwm_duty
- *  Set the PWM duty cycle of the provided pin to the provided value
- *  Optionally allows inverting the duty cycle [default = false]
- *  Optionally allows changing the maximum size of the provided value to enable finer PWM duty control [default = 255]
- */
-void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size=255, const bool invert=false);
+// ------------------------
+// Free Memory Accessor
+// ------------------------

-// Reset source
-void HAL_clear_reset_source(void);
-uint8_t HAL_get_reset_source(void);
+#pragma GCC diagnostic push
+#if GCC_VERSION <= 50000
+  #pragma GCC diagnostic ignored "-Wunused-function"
+#endif

-void HAL_reboot();
+int freeMemory();
+
+#pragma GCC diagnostic pop
+
+// ------------------------
+// MarlinHAL Class
+// ------------------------
+
+class MarlinHAL {
+public:
+
+  // Earliest possible init, before setup()
+  MarlinHAL() {}
+
+  static void init();          // Called early in setup()
+  static void init_board() {}  // Called less early in setup()
+  static void reboot();        // Restart the firmware from 0x0
+
+  // Interrupts
+  static bool isr_state() { return !__get_PRIMASK(); }
+  static void isr_on()  { __enable_irq(); }
+  static void isr_off() { __disable_irq(); }
+
+  static void delay_ms(const int ms) { _delay_ms(ms); }
+
+  // Watchdog
+  static void watchdog_init() IF_DISABLED(USE_WATCHDOG, {});
+  static void watchdog_refresh() IF_DISABLED(USE_WATCHDOG, {});
+  static bool watchdog_timed_out() IF_DISABLED(USE_WATCHDOG, { return false; });
+  static void watchdog_clear_timeout_flag() IF_DISABLED(USE_WATCHDOG, {});
+
+  // Tasks, called from idle()
+  static void idletask();
+
+  // Reset
+  static uint8_t get_reset_source();
+  static void clear_reset_source();
+
+  // Free SRAM
+  static int freeMemory() { return ::freeMemory(); }
+
+  //
+  // ADC Methods
+  //
+
+  using FilteredADC = LPC176x::ADC<ADC_LOWPASS_K_VALUE, ADC_MEDIAN_FILTER_SIZE>;
+
+  // Called by Temperature::init once at startup
+  static void adc_init() {}
+
+  // Called by Temperature::init for each sensor at startup
+  static void adc_enable(const pin_t pin) {
+    FilteredADC::enable_channel(pin);
+  }
+
+  // Begin ADC sampling on the given pin. Called from Temperature::isr!
+  static uint32_t adc_result;
+  static void adc_start(const pin_t pin) {
+    adc_result = FilteredADC::read(pin) >> (16 - HAL_ADC_RESOLUTION); // returns 16bit value, reduce to required bits
+  }
+
+  // Is the ADC ready for reading?
+  static bool adc_ready() { return true; }
+
+  // The current value of the ADC register
+  static uint16_t adc_value() { return uint16_t(adc_result); }
+
+  /**
+   * Set the PWM duty cycle for the pin to the given value.
+   * Optionally invert the duty cycle [default = false]
+   * Optionally change the scale of the provided value to enable finer PWM duty control [default = 255]
+   */
+  static void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size=255, const bool invert=false);
+
+  /**
+   * Set the frequency of the timer corresponding to the provided pin
+   * All Hardware PWM pins will run at the same frequency and
+   * All Software PWM pins will run at the same frequency
+   */
+  static void set_pwm_frequency(const pin_t pin, const uint16_t f_desired);
+};
@@ -46,6 +46,8 @@ public:

  void end() {}

+  uint8_t availableForWrite(void) { /* flushTX(); */ return TX_BUFFER_SIZE; }
+
  #if ENABLED(EMERGENCY_PARSER)
    bool recv_callback(const char c) override;
  #endif
@@ -26,7 +26,7 @@

 #if ENABLED(POSTMORTEM_DEBUGGING)

-#include "../shared/HAL_MinSerial.h"
+#include "../shared/MinSerial.h"
 #include <debug_frmwrk.h>

 static void TX(char c) { _DBC(c); }
@@ -65,4 +65,5 @@ class libServo: public Servo {
  }
 };

-#define HAL_SERVO_LIB libServo
+class libServo;
+typedef libServo hal_servo_t;
@@ -1,10 +1,9 @@
 /**
 * Marlin 3D Printer Firmware
- *
 * Copyright (c) 2020 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
- * Copyright (c) 2016 Bob Cousins bobcousins42@googlemail.com
- * Copyright (c) 2015-2016 Nico Tonnhofer wurstnase.reprap@gmail.com
- * Copyright (c) 2016 Victor Perez victor_pv@hotmail.com
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
@@ -20,12 +19,19 @@
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 *
 */
+
+/**
+ * Implementation of EEPROM settings in SD Card
+ */
+
 #ifdef TARGET_LPC1768

 #include "../../inc/MarlinConfig.h"

 #if ENABLED(SDCARD_EEPROM_EMULATION)

+//#define DEBUG_SD_EEPROM_EMULATION
+
 #include "../shared/eeprom_api.h"

 #include <chanfs/diskio.h>
@@ -38,9 +44,11 @@ FATFS fat_fs;
 FIL eeprom_file;
 bool eeprom_file_open = false;

+#define EEPROM_FILENAME "eeprom.dat"
 #ifndef MARLIN_EEPROM_SIZE
  #define MARLIN_EEPROM_SIZE size_t(0x1000) // 4KiB of Emulated EEPROM
 #endif
+
 size_t PersistentStore::capacity() { return MARLIN_EEPROM_SIZE; }

 bool PersistentStore::access_start() {
@@ -50,7 +58,7 @@ bool PersistentStore::access_start() {
    MSC_Release_Lock();
    return false;
  }
-  FRESULT res = f_open(&eeprom_file, "eeprom.dat", FA_OPEN_ALWAYS | FA_WRITE | FA_READ);
+  FRESULT res = f_open(&eeprom_file, EEPROM_FILENAME, FA_OPEN_ALWAYS | FA_WRITE | FA_READ);
  if (res) MSC_Release_Lock();

  if (res == FR_OK) {
@@ -81,18 +89,20 @@ bool PersistentStore::access_finish() {
 // This extra chit-chat goes away soon, but is helpful for now
 // to see errors that are happening in read_data / write_data
 static void debug_rw(const bool write, int &pos, const uint8_t *value, const size_t size, const FRESULT s, const size_t total=0) {
-  PGM_P const rw_str = write ? PSTR("write") : PSTR("read");
-  SERIAL_CHAR(' ');
-  SERIAL_ECHOPGM_P(rw_str);
-  SERIAL_ECHOLNPAIR("_data(", pos, ",", value, ",", size, ", ...)");
-  if (total) {
-    SERIAL_ECHOPGM(" f_");
-    SERIAL_ECHOPGM_P(rw_str);
-    SERIAL_ECHOPAIR("()=", s, "\n size=", size, "\n bytes_");
-    SERIAL_ECHOLNPAIR_P(write ? PSTR("written=") : PSTR("read="), total);
-  }
-  else
-    SERIAL_ECHOLNPAIR(" f_lseek()=", s);
+  #if ENABLED(DEBUG_SD_EEPROM_EMULATION)
+    FSTR_P const rw_str = write ? F("write") : F("read");
+    SERIAL_CHAR(' ');
+    SERIAL_ECHOF(rw_str);
+    SERIAL_ECHOLNPGM("_data(", pos, ",", *value, ",", size, ", ...)");
+    if (total) {
+      SERIAL_ECHOPGM(" f_");
+      SERIAL_ECHOF(rw_str);
+      SERIAL_ECHOPGM("()=", s, "\n size=", size, "\n bytes_");
+      SERIAL_ECHOLNF(write ? F("written=") : F("read="), total);
+    }
+    else
+      SERIAL_ECHOLNPGM(" f_lseek()=", s);
+  #endif
 }

 // File function return codes for type FRESULT. This goes away soon, but
@@ -34,7 +34,7 @@
 #include "../shared/eeprom_api.h"

 #ifndef MARLIN_EEPROM_SIZE
-  #define MARLIN_EEPROM_SIZE           0x8000 // 32KB‬
+  #define MARLIN_EEPROM_SIZE           0x8000 // 32K
 #endif
 size_t PersistentStore::capacity()    { return MARLIN_EEPROM_SIZE; }

@@ -155,4 +155,37 @@ void setup_endstop_interrupts() {
    #endif
    _ATTACH(K_MIN_PIN);
  #endif
+  #if HAS_U_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(U_MAX_PIN)
+      #error "U_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(U_MAX_PIN);
+  #elif HAS_U_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(U_MIN_PIN)
+      #error "U_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(U_MIN_PIN);
+  #endif
+  #if HAS_V_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(V_MAX_PIN)
+      #error "V_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(V_MAX_PIN);
+  #elif HAS_V_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(V_MIN_PIN)
+      #error "V_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(V_MIN_PIN);
+  #endif
+  #if HAS_W_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(W_MAX_PIN)
+      #error "W_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(W_MAX_PIN);
+  #elif HAS_W_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(W_MIN_PIN)
+      #error "W_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(W_MIN_PIN);
+  #endif
 }
@@ -21,19 +21,17 @@
 */
 #ifdef TARGET_LPC1768

-#include "../../inc/MarlinConfigPre.h"
-
-#if NEEDS_HARDWARE_PWM // Specific meta-flag for features that mandate PWM
-
+#include "../../inc/MarlinConfig.h"
 #include <pwm.h>

-void set_pwm_frequency(const pin_t pin, int f_desired) {
+void MarlinHAL::set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=255*/, const bool invert/*=false*/) {
+  if (!LPC176x::pin_is_valid(pin)) return;
+  if (LPC176x::pwm_attach_pin(pin))
+    LPC176x::pwm_write_ratio(pin, invert ? 1.0f - (float)v / v_size : (float)v / v_size);  // map 1-254 onto PWM range
+}
+
+void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
  LPC176x::pwm_set_frequency(pin, f_desired);
 }

-void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size/*=255*/, const bool invert/*=false*/) {
-  LPC176x::pwm_write_ratio(pin, invert ? 1.0f - (float)v / v_size : (float)v / v_size);
-}
-
-#endif // NEEDS_HARDWARE_PWM
 #endif // TARGET_LPC1768
@@ -67,7 +67,7 @@ static_assert(!(NUM_SERVOS && ENABLED(FAST_PWM_FAN)), "BLTOUCH and Servos are in
 * Test LPC176x-specific configuration values for errors at compile-time.
 */

-//#if ENABLED(SPINDLE_LASER_PWM) && !(SPINDLE_LASER_PWM_PIN == 4 || SPINDLE_LASER_PWM_PIN == 6 || SPINDLE_LASER_PWM_PIN == 11)
+//#if ENABLED(SPINDLE_LASER_USE_PWM) && !(SPINDLE_LASER_PWM_PIN == 4 || SPINDLE_LASER_PWM_PIN == 6 || SPINDLE_LASER_PWM_PIN == 11)
 //  #error "SPINDLE_LASER_PWM_PIN must use SERVO0, SERVO1 or SERVO3 connector"
 //#endif

@@ -113,7 +113,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
  #define _IS_RX1_1 IS_RX1
  #if IS_TX1(TMC_SW_SCK)
    #error "Serial port pins (1) conflict with other pins!"
-  #elif HAS_WIRED_LCD
+  #elif HAS_ROTARY_ENCODER
    #if IS_TX1(BTN_EN2) || IS_RX1(BTN_EN1)
      #error "Serial port pins (1) conflict with Encoder Buttons!"
    #elif ANY_TX(1, SD_SCK_PIN, LCD_PINS_D4, DOGLCD_SCK, LCD_RESET_PIN, LCD_PINS_RS, SHIFT_CLK_PIN) \
--- a/Show More
+++ b/Show More