Update Configuration.h

See #20649

.editorconfig

@@ -4,10 +4,10 @@ root = true
 [{*.patch,syntax_test_*}]
 trim_trailing_whitespace = false
 
-[{*.c,*.cpp,*.h}]
+[{*.c,*.cpp,*.h,*.ino}]
 charset = utf-8
 
-[{*.c,*.cpp,*.h,Makefile}]
+[{*.c,*.cpp,*.h,*.ino,Makefile}]
 trim_trailing_whitespace = true
 insert_final_newline = true
 end_of_line = lf

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,43 @@
+---
+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.

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,17 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Marlin Documentation
+    url: http://marlinfw.org/
+    about: Lots of documentation on installing and using Marlin.
+  - name: MarlinFirmware Facebook group
+    url: https://www.facebook.com/groups/1049718498464482
+    about: Please ask and answer questions here.
+  - 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
+    about: A searchable web forum hosted by RepRap dot org.
+  - 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!

.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,35 @@
+---
+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.

.github/workflows/bad-target.md

@@ -0,0 +1,7 @@
+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.

.github/workflows/bump-date.yml

@@ -0,0 +1,34 @@
+#
+# bump-date.yml
+# Bump the distribution date once per day
+#
+
+name: Bump Distribution Date
+
+on:
+  schedule:
+    - cron: '0 0 * * *'
+
+jobs:
+  bump_date:
+
+    runs-on: ubuntu-latest
+
+    steps:
+
+    - name: Check out bugfix-2.0.x
+      uses: actions/checkout@v2
+      with:
+        ref: bugfix-2.0.x
+
+    - 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

.github/workflows/check-pr.yml

@@ -0,0 +1,27 @@
+#
+# comment-pr.yml
+# Add a comment to any PR directed to a release branch
+#
+
+name: PR Bad Target
+
+on:
+  pull_request:
+    branches:
+    - 1.0.x
+    - 1.1.x
+    - 2.0.x
+
+jobs:
+  bad_target:
+
+    name: PR Bad Target
+    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

.github/workflows/test-builds.yml

@@ -56,28 +56,33 @@ jobs:
 
         # STM32F1 (Maple) Environments
 
-        - STM32F103RC_btt
-        - STM32F103RC_btt_USB
-        - STM32F103RE_btt
-        - STM32F103RE_btt_USB
-        - STM32F103RC_fysetc
+        #- STM32F103RC_btt_maple
+        - STM32F103RC_btt_USB_maple
+        - STM32F103RC_fysetc_maple
         - STM32F103RC_meeb
-        - jgaurora_a5s_a1
-        - STM32F103VE_longer
-        - mks_robin
-        - mks_robin_lite
-        - mks_robin_pro
-        - STM32F103RET6_creality
-        - mks_robin_nano35
+        - 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
+        - STM32F103VE_ZM3E4V2_USB_maple
 
         # STM32 (ST) Environments
 
+        - STM32F103RC_btt
+        #- STM32F103RC_btt_USB
+        - STM32F103RE_btt
+        - STM32F103RE_btt_USB
+        - STM32F103RET6_creality
+        - STM32F103VE_longer
         - STM32F407VE_black
         - STM32F401VE_STEVAL
         - BIGTREE_BTT002
         - BIGTREE_SKR_PRO
         - BIGTREE_GTR_V1_0
-        - mks_robin_stm32
+        - mks_robin
         - ARMED
         - FYSETC_S6
         - STM32F070CB_malyan
@@ -86,9 +91,12 @@ jobs:
         - FLYF407ZG
         - rumba32
         - LERDGEX
-        - mks_robin_nano35_stm32
+        - LERDGEK
+        - mks_robin_nano35
         - NUCLEO_F767ZI
         - REMRAM_V1
+        - BTT_SKR_SE_BX
+        - chitu_f103
 
         # Put lengthy tests last
 
@@ -98,12 +106,30 @@ jobs:
         # Non-working environment tests
         #- at90usb1286_cdc
         #- STM32F103CB_malyan
+        #- STM32F103RE
         #- mks_robin_mini
 
     steps:
 
+    - name: Check out the PR
+      uses: actions/checkout@v2
+
+    - name: Cache pip
+      uses: actions/cache@v2
+      with:
+        path: ~/.cache/pip
+        key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
+        restore-keys: |
+          ${{ runner.os }}-pip-
+
+    - name: Cache PlatformIO
+      uses: actions/cache@v2
+      with:
+        path: ~/.platformio
+        key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}
+
     - name: Select Python 3.7
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v2
       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
@@ -113,9 +139,6 @@ jobs:
         pip install -U https://github.com/platformio/platformio-core/archive/develop.zip
         platformio update
 
-    - name: Check out the PR
-      uses: actions/checkout@v2
-
     - name: Run ${{ matrix.test-platform }} Tests
       run: |
         make tests-single-ci TEST_TARGET=${{ matrix.test-platform }}

.gitignore

@@ -122,29 +122,6 @@ tags
 .gcc-flags.json
 /lib/
 
-# Workaround for Deviot+platformio quirks
-Marlin/lib
-Marlin/platformio.ini
-Marlin/*/platformio.ini
-Marlin/*/*/platformio.ini
-Marlin/*/*/*/platformio.ini
-Marlin/*/*/*/*/platformio.ini
-Marlin/.travis.yml
-Marlin/*/.travis.yml
-Marlin/*/*/.travis.yml
-Marlin/*/*/*/.travis.yml
-Marlin/*/*/*/*/.travis.yml
-Marlin/.gitignore
-Marlin/*/.gitignore
-Marlin/*/*/.gitignore
-Marlin/*/*/*/.gitignore
-Marlin/*/*/*/*/.gitignore
-Marlin/readme.txt
-Marlin/*/readme.txt
-Marlin/*/*/readme.txt
-Marlin/*/*/*/readme.txt
-Marlin/*/*/*/*/readme.txt
-
 # Secure Credentials
 Configuration_Secure.h
 
@@ -166,7 +143,11 @@ vc-fileutils.settings
 .vscode/launch.json
 .vscode/*.db
 
-# cmake
+#Simulation
+imgui.ini
+eeprom.dat
+
+#cmake
 CMakeLists.txt
 src/CMakeLists.txt
 CMakeListsPrivate.txt

Marlin/Makefile

@@ -110,7 +110,7 @@ LIQUID_TWI2        ?= 0
 WIRE               ?= 0
 
 # This defines if Tone is needed (i.e SPEAKER is defined in Configuration.h)
-# Disabling this (and SPEAKER) saves approximatively 350 bytes of memory.
+# Disabling this (and SPEAKER) saves approximately 350 bytes of memory.
 TONE               ?= 1
 
 # This defines if U8GLIB is needed (may require RELOC_WORKAROUND)
@@ -219,7 +219,7 @@ else ifeq ($(HARDWARE_MOTHERBOARD),1111)
 else ifeq ($(HARDWARE_MOTHERBOARD),1112)
 # MKS GEN L
 else ifeq ($(HARDWARE_MOTHERBOARD),1113)
-# zrib V2.0 control board (Chinese knock off RAMPS replica)
+# zrib V2.0 control board (Chinese RAMPS replica)
 else ifeq ($(HARDWARE_MOTHERBOARD),1114)
 # BigTreeTech or BIQU KFB2.0
 else ifeq ($(HARDWARE_MOTHERBOARD),1115)
@@ -323,6 +323,8 @@ else ifeq ($(HARDWARE_MOTHERBOARD),1203)
 else ifeq ($(HARDWARE_MOTHERBOARD),1204)
 # abee Scoovo X9H
 else ifeq ($(HARDWARE_MOTHERBOARD),1205)
+# Rambo ThinkerV2
+else ifeq ($(HARDWARE_MOTHERBOARD),1206)
 
 #
 # Other ATmega1280, ATmega2560
@@ -991,5 +993,5 @@ clean:
 
 .PHONY: all build elf hex eep lss sym program coff extcoff clean depend sizebefore sizeafter
 
-# Automaticaly include the dependency files created by gcc
+# Automatically include the dependency files created by gcc
 -include ${patsubst %.o, %.d, ${OBJ}}

Marlin/Version.h

@@ -41,7 +41,7 @@
  * here we define this default string as the date where the latest release
  * version was tagged.
  */
-//#define STRING_DISTRIBUTION_DATE "2019-07-10"
+//#define STRING_DISTRIBUTION_DATE "2021-08-08"
 
 /**
  * Defines a generic printer name to be output to the LCD after booting Marlin.

Marlin/src/HAL/AVR/HAL.cpp

@@ -25,7 +25,7 @@
 #include "HAL.h"
 
 #ifdef USBCON
-  DefaultSerial MSerial(false, Serial);
+  DefaultSerial1 MSerial0(false, Serial);
   #ifdef BLUETOOTH
     BTSerial btSerial(false, bluetoothSerial);
   #endif
@@ -58,6 +58,15 @@ void HAL_init() {
   #endif
 }
 
+void HAL_reboot() {
+  #if ENABLED(USE_WATCHDOG)
+    while (1) { /* run out the watchdog */ }
+  #else
+    void (*resetFunc)() = 0;  // Declare resetFunc() at address 0
+    resetFunc();              // Jump to address 0
+  #endif
+}
+
 #if ENABLED(SDSUPPORT)
 
   #include "../../sd/SdFatUtil.h"

Marlin/src/HAL/AVR/HAL.h

@@ -83,38 +83,45 @@ typedef int8_t pin_t;
 // Serial ports
 #ifdef USBCON
   #include "../../core/serial_hook.h"
-  typedef ForwardSerial0Type< decltype(Serial) > DefaultSerial;
-  extern DefaultSerial MSerial;
+  typedef ForwardSerial1Class< decltype(Serial) > DefaultSerial1;
+  extern DefaultSerial1 MSerial0;
   #ifdef BLUETOOTH
-    typedef ForwardSerial0Type< decltype(bluetoothSerial) > BTSerial;
+    typedef ForwardSerial1Class< decltype(bluetoothSerial) > BTSerial;
     extern BTSerial btSerial;
   #endif
 
-  #define MYSERIAL0 TERN(BLUETOOTH, btSerial, MSerial)
+  #define MYSERIAL1 TERN(BLUETOOTH, btSerial, MSerial0)
 #else
   #if !WITHIN(SERIAL_PORT, -1, 3)
-    #error "SERIAL_PORT must be from -1 to 3. Please update your configuration."
+    #error "SERIAL_PORT must be from 0 to 3, or -1 for USB Serial."
   #endif
-  #define MYSERIAL0 customizedSerial1
+  #define MYSERIAL1 customizedSerial1
 
   #ifdef SERIAL_PORT_2
     #if !WITHIN(SERIAL_PORT_2, -1, 3)
-      #error "SERIAL_PORT_2 must be from -1 to 3. Please update your configuration."
+      #error "SERIAL_PORT_2 must be from 0 to 3, or -1 for USB Serial."
     #endif
-    #define MYSERIAL1 customizedSerial2
+    #define MYSERIAL2 customizedSerial2
+  #endif
+
+  #ifdef SERIAL_PORT_3
+    #if !WITHIN(SERIAL_PORT_3, -1, 3)
+      #error "SERIAL_PORT_3 must be from 0 to 3, or -1 for USB Serial."
+    #endif
+    #define MYSERIAL3 customizedSerial3
   #endif
 #endif
 
 #ifdef MMU2_SERIAL_PORT
   #if !WITHIN(MMU2_SERIAL_PORT, -1, 3)
-    #error "MMU2_SERIAL_PORT must be from -1 to 3. Please update your configuration."
+    #error "MMU2_SERIAL_PORT must be from 0 to 3, or -1 for USB Serial."
   #endif
   #define MMU2_SERIAL mmuSerial
 #endif
 
 #ifdef LCD_SERIAL_PORT
   #if !WITHIN(LCD_SERIAL_PORT, -1, 3)
-    #error "LCD_SERIAL_PORT must be from -1 to 3. Please update your configuration."
+    #error "LCD_SERIAL_PORT must be from 0 to 3, or -1 for USB Serial."
   #endif
   #define LCD_SERIAL lcdSerial
   #if HAS_DGUS_LCD
@@ -135,7 +142,7 @@ void HAL_init();
 inline void HAL_clear_reset_source() { MCUSR = 0; }
 inline uint8_t HAL_get_reset_source() { return MCUSR; }
 
-inline void HAL_reboot() {}  // reboot the board or restart the bootloader
+void HAL_reboot();
 
 #if GCC_VERSION <= 50000
   #pragma GCC diagnostic push
@@ -179,7 +186,7 @@ inline void HAL_adc_init() {
 #define GET_PIN_MAP_INDEX(pin) pin
 #define PARSED_PIN_INDEX(code, dval) parser.intval(code, dval)
 
-#define HAL_SENSITIVE_PINS 0, 1
+#define HAL_SENSITIVE_PINS 0, 1,
 
 #ifdef __AVR_AT90USB1286__
   #define JTAG_DISABLE() do{ MCUCR = 0x80; MCUCR = 0x80; }while(0)

Marlin/src/HAL/AVR/HAL_SPI.cpp

@@ -88,7 +88,7 @@ void spiBegin() {
   }
 
   /** SPI read data  */
-  void spiRead(uint8_t* buf, uint16_t nbyte) {
+  void spiRead(uint8_t *buf, uint16_t nbyte) {
     if (nbyte-- == 0) return;
     SPDR = 0xFF;
     for (uint16_t i = 0; i < nbyte; i++) {
@@ -107,7 +107,7 @@ void spiBegin() {
   }
 
   /** SPI send block  */
-  void spiSendBlock(uint8_t token, const uint8_t* buf) {
+  void spiSendBlock(uint8_t token, const uint8_t *buf) {
     SPDR = token;
     for (uint16_t i = 0; i < 512; i += 2) {
       while (!TEST(SPSR, SPIF)) { /* Intentionally left empty */ }
@@ -215,7 +215,7 @@ void spiBegin() {
   }
 
   // Soft SPI read data
-  void spiRead(uint8_t* buf, uint16_t nbyte) {
+  void spiRead(uint8_t *buf, uint16_t nbyte) {
     for (uint16_t i = 0; i < nbyte; i++)
       buf[i] = spiRec();
   }
@@ -242,7 +242,7 @@ void spiBegin() {
   }
 
   // Soft SPI send block
-  void spiSendBlock(uint8_t token, const uint8_t* buf) {
+  void spiSendBlock(uint8_t token, const uint8_t *buf) {
     spiSend(token);
     for (uint16_t i = 0; i < 512; i++)
       spiSend(buf[i]);

Marlin/src/HAL/AVR/MarlinSerial.cpp

@@ -454,7 +454,7 @@ void MarlinSerial<Cfg>::flush() {
 }
 
 template<typename Cfg>
-size_t MarlinSerial<Cfg>::write(const uint8_t c) {
+void MarlinSerial<Cfg>::write(const uint8_t c) {
   if (Cfg::TX_SIZE == 0) {
 
     _written = true;
@@ -480,7 +480,7 @@ size_t MarlinSerial<Cfg>::write(const uint8_t c) {
       // location". This makes sure flush() won't return until the bytes
       // actually got written
       B_TXC = 1;
-      return 1;
+      return;
     }
 
     const uint8_t i = (tx_buffer.head + 1) & (Cfg::TX_SIZE - 1);
@@ -510,7 +510,6 @@ size_t MarlinSerial<Cfg>::write(const uint8_t c) {
     // Enable TX ISR - Non atomic, but it will eventually enable TX ISR
     B_UDRIE = 1;
   }
-  return 1;
 }
 
 template<typename Cfg>
@@ -568,7 +567,7 @@ ISR(SERIAL_REGNAME(USART, SERIAL_PORT, _UDRE_vect)) {
 
 // Because of the template definition above, it's required to instantiate the template to have all methods generated
 template class MarlinSerial< MarlinSerialCfg<SERIAL_PORT> >;
-MSerialT customizedSerial1(MSerialT::HasEmergencyParser);
+MSerialT1 customizedSerial1(MSerialT1::HasEmergencyParser);
 
 #ifdef SERIAL_PORT_2
 
@@ -583,7 +582,24 @@ MSerialT customizedSerial1(MSerialT::HasEmergencyParser);
 
   template class MarlinSerial< MarlinSerialCfg<SERIAL_PORT_2> >;
   MSerialT2 customizedSerial2(MSerialT2::HasEmergencyParser);
-#endif
+
+#endif // SERIAL_PORT_2
+
+#ifdef SERIAL_PORT_3
+
+  // Hookup ISR handlers
+  ISR(SERIAL_REGNAME(USART, SERIAL_PORT_3, _RX_vect)) {
+    MarlinSerial<MarlinSerialCfg<SERIAL_PORT_3>>::store_rxd_char();
+  }
+
+  ISR(SERIAL_REGNAME(USART, SERIAL_PORT_3, _UDRE_vect)) {
+    MarlinSerial<MarlinSerialCfg<SERIAL_PORT_3>>::_tx_udr_empty_irq();
+  }
+
+  template class MarlinSerial< MarlinSerialCfg<SERIAL_PORT_3> >;
+  MSerialT3 customizedSerial3(MSerialT3::HasEmergencyParser);
+
+#endif // SERIAL_PORT_3
 
 #ifdef MMU2_SERIAL_PORT
 
@@ -596,8 +612,9 @@ MSerialT customizedSerial1(MSerialT::HasEmergencyParser);
   }
 
   template class MarlinSerial< MMU2SerialCfg<MMU2_SERIAL_PORT> >;
-  MSerialT3 mmuSerial(MSerialT3::HasEmergencyParser);
-#endif
+  MSerialMMU2 mmuSerial(MSerialMMU2::HasEmergencyParser);
+
+#endif // MMU2_SERIAL_PORT
 
 #ifdef LCD_SERIAL_PORT
 
@@ -610,7 +627,7 @@ MSerialT customizedSerial1(MSerialT::HasEmergencyParser);
   }
 
   template class MarlinSerial< LCDSerialCfg<LCD_SERIAL_PORT> >;
-  MSerialT4 lcdSerial(MSerialT4::HasEmergencyParser);
+  MSerialLCD lcdSerial(MSerialLCD::HasEmergencyParser);
 
   #if HAS_DGUS_LCD
     template<typename Cfg>
@@ -623,13 +640,13 @@ MSerialT customizedSerial1(MSerialT::HasEmergencyParser);
     }
   #endif
 
-#endif
+#endif // LCD_SERIAL_PORT
 
 #endif // !USBCON && (UBRRH || UBRR0H || UBRR1H || UBRR2H || UBRR3H)
 
 // For AT90USB targets use the UART for BT interfacing
 #if defined(USBCON) && ENABLED(BLUETOOTH)
-  MSerialT5 bluetoothSerial(false);
+  MSerialBT bluetoothSerial(false);
 #endif
 
 #endif // __AVR__

Marlin/src/HAL/AVR/MarlinSerial.h

@@ -210,7 +210,7 @@
     static int read();
     static void flush();
     static ring_buffer_pos_t available();
-    static size_t write(const uint8_t c);
+    static void write(const uint8_t c);
     static void flushTX();
     #if HAS_DGUS_LCD
       static ring_buffer_pos_t get_tx_buffer_free();
@@ -238,66 +238,60 @@
     static constexpr bool MAX_RX_QUEUED     = ENABLED(SERIAL_STATS_MAX_RX_QUEUED);
   };
 
-  typedef Serial0Type< MarlinSerial< MarlinSerialCfg<SERIAL_PORT> > > MSerialT;
-  extern MSerialT customizedSerial1;
+  typedef Serial1Class< MarlinSerial< MarlinSerialCfg<SERIAL_PORT> > > MSerialT1;
+  extern MSerialT1 customizedSerial1;
 
   #ifdef SERIAL_PORT_2
-    typedef Serial0Type< MarlinSerial< MarlinSerialCfg<SERIAL_PORT_2> > > MSerialT2;
+    typedef Serial1Class< MarlinSerial< MarlinSerialCfg<SERIAL_PORT_2> > > MSerialT2;
     extern MSerialT2 customizedSerial2;
   #endif
 
+  #ifdef SERIAL_PORT_3
+    typedef Serial1Class< MarlinSerial< MarlinSerialCfg<SERIAL_PORT_3> > > MSerialT3;
+    extern MSerialT3 customizedSerial3;
+  #endif
+
 #endif // !USBCON
 
 #ifdef MMU2_SERIAL_PORT
   template <uint8_t serial>
   struct MMU2SerialCfg {
     static constexpr int PORT               = serial;
+    static constexpr unsigned int RX_SIZE   = 32;
+    static constexpr unsigned int TX_SIZE   = 32;
     static constexpr bool XONOFF            = false;
     static constexpr bool EMERGENCYPARSER   = false;
     static constexpr bool DROPPED_RX        = false;
     static constexpr bool RX_FRAMING_ERRORS = false;
     static constexpr bool MAX_RX_QUEUED     = false;
-    static constexpr unsigned int RX_SIZE   = 32;
-    static constexpr unsigned int TX_SIZE   = 32;
     static constexpr bool RX_OVERRUNS       = false;
   };
 
-  typedef Serial0Type< MarlinSerial< MMU2SerialCfg<MMU2_SERIAL_PORT> > > MSerialT3;
-  extern MSerialT3 mmuSerial;
+  typedef Serial1Class< MarlinSerial< MMU2SerialCfg<MMU2_SERIAL_PORT> > > MSerialMMU2;
+  extern MSerialMMU2 mmuSerial;
 #endif
 
 #ifdef LCD_SERIAL_PORT
 
   template <uint8_t serial>
   struct LCDSerialCfg {
-    static constexpr int PORT                 = serial;
-    static constexpr bool XONOFF              = false;
-    static constexpr bool EMERGENCYPARSER     = ENABLED(EMERGENCY_PARSER);
-    static constexpr bool DROPPED_RX          = false;
-    static constexpr bool RX_FRAMING_ERRORS   = false;
-    static constexpr bool MAX_RX_QUEUED       = false;
-    #if HAS_DGUS_LCD
-      static constexpr unsigned int RX_SIZE   = DGUS_RX_BUFFER_SIZE;
-      static constexpr unsigned int TX_SIZE   = DGUS_TX_BUFFER_SIZE;
-      static constexpr bool RX_OVERRUNS       = ENABLED(SERIAL_STATS_RX_BUFFER_OVERRUNS);
-    #elif EITHER(ANYCUBIC_LCD_I3MEGA, ANYCUBIC_LCD_CHIRON)
-      static constexpr unsigned int RX_SIZE   = 64;
-      static constexpr unsigned int TX_SIZE   = 128;
-      static constexpr bool RX_OVERRUNS       = false;
-    #else
-      static constexpr unsigned int RX_SIZE   = 64;
-      static constexpr unsigned int TX_SIZE   = 128;
-      static constexpr bool RX_OVERRUNS       = false
-    #endif
+    static constexpr int PORT               = serial;
+    static constexpr unsigned int RX_SIZE   = TERN(HAS_DGUS_LCD, DGUS_RX_BUFFER_SIZE,  64);
+    static constexpr unsigned int TX_SIZE   = TERN(HAS_DGUS_LCD, DGUS_TX_BUFFER_SIZE, 128);
+    static constexpr bool XONOFF            = false;
+    static constexpr bool EMERGENCYPARSER   = ENABLED(EMERGENCY_PARSER);
+    static constexpr bool DROPPED_RX        = false;
+    static constexpr bool RX_FRAMING_ERRORS = false;
+    static constexpr bool MAX_RX_QUEUED     = false;
+    static constexpr bool RX_OVERRUNS       = BOTH(HAS_DGUS_LCD, SERIAL_STATS_RX_BUFFER_OVERRUNS);
   };
 
-
-  typedef Serial0Type< MarlinSerial< LCDSerialCfg<LCD_SERIAL_PORT> > > MSerialT4;
-  extern MSerialT4 lcdSerial;
+  typedef Serial1Class< MarlinSerial< LCDSerialCfg<LCD_SERIAL_PORT> > > MSerialLCD;
+  extern MSerialLCD lcdSerial;
 #endif
 
 // Use the UART for Bluetooth in AT90USB configurations
 #if defined(USBCON) && ENABLED(BLUETOOTH)
-  typedef Serial0Type<HardwareSerial> MSerialT5;
-  extern MSerialT5 bluetoothSerial;
+  typedef Serial1Class<HardwareSerial> MSerialBT;
+  extern MSerialBT bluetoothSerial;
 #endif

Marlin/src/HAL/AVR/eeprom.cpp

@@ -40,13 +40,13 @@ bool PersistentStore::access_start()  { return true; }
 bool PersistentStore::access_finish() { return true; }
 
 bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  uint16_t written = 0;
   while (size--) {
     uint8_t * const p = (uint8_t * const)pos;
     uint8_t v = *value;
-    // EEPROM has only ~100,000 write cycles,
-    // so only write bytes that have changed!
-    if (v != eeprom_read_byte(p)) {
+    if (v != eeprom_read_byte(p)) { // EEPROM has only ~100,000 write cycles, so only write bytes that have changed!
       eeprom_write_byte(p, v);
+      if (++written & 0x7F) delay(2); else safe_delay(2); // Avoid triggering watchdog during long EEPROM writes
       if (eeprom_read_byte(p) != v) {
         SERIAL_ECHO_MSG(STR_ERR_EEPROM_WRITE);
         return true;

Marlin/src/HAL/AVR/endstop_interrupts.h

@@ -168,6 +168,51 @@ void setup_endstop_interrupts() {
       pciSetup(Z_MIN_PIN);
     #endif
   #endif
+  #if HAS_I_MAX
+    #if (digitalPinToInterrupt(I_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(I_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(I_MAX_PIN), "I_MAX_PIN is not interrupt-capable");
+      pciSetup(I_MAX_PIN);
+    #endif
+  #elif HAS_I_MIN
+    #if (digitalPinToInterrupt(I_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(I_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(I_MIN_PIN), "I_MIN_PIN is not interrupt-capable");
+      pciSetup(I_MIN_PIN);
+    #endif
+  #endif
+  #if HAS_J_MAX
+    #if (digitalPinToInterrupt(J_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(J_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(J_MAX_PIN), "J_MAX_PIN is not interrupt-capable");
+      pciSetup(J_MAX_PIN);
+    #endif
+  #elif HAS_J_MIN
+    #if (digitalPinToInterrupt(J_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(J_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(J_MIN_PIN), "J_MIN_PIN is not interrupt-capable");
+      pciSetup(J_MIN_PIN);
+    #endif
+  #endif
+  #if HAS_K_MAX
+    #if (digitalPinToInterrupt(K_MAX_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(K_MAX_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(K_MAX_PIN), "K_MAX_PIN is not interrupt-capable");
+      pciSetup(K_MAX_PIN);
+    #endif
+  #elif HAS_K_MIN
+    #if (digitalPinToInterrupt(K_MIN_PIN) != NOT_AN_INTERRUPT)
+      _ATTACH(K_MIN_PIN);
+    #else
+      static_assert(digitalPinHasPCICR(K_MIN_PIN), "K_MIN_PIN is not interrupt-capable");
+      pciSetup(K_MIN_PIN);
+    #endif
+  #endif
   #if HAS_X2_MAX
     #if (digitalPinToInterrupt(X2_MAX_PIN) != NOT_AN_INTERRUPT)
       _ATTACH(X2_MAX_PIN);
@@ -256,6 +301,5 @@ 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.
 }

Marlin/src/HAL/AVR/fastio.cpp

@@ -241,7 +241,7 @@ uint8_t extDigitalRead(const int8_t pin) {
  *
  * DC values -1.0 to 1.0. Negative duty cycle inverts the pulse.
  */
-uint16_t set_pwm_frequency_hz(const float &hz, const float dca, const float dcb, const float dcc) {
+uint16_t set_pwm_frequency_hz(const_float_t hz, const float dca, const float dcb, const float dcc) {
   float count = 0;
   if (hz > 0 && (dca || dcb || dcc)) {
     count = float(F_CPU) / hz;            // 1x prescaler, TOP for 16MHz base freq.

Marlin/src/HAL/AVR/fastio.h

@@ -284,8 +284,8 @@ enum ClockSource2 : char {
  * PWM availability macros
  */
 
-// Determine which harware PWMs are already in use
-#define _PWM_CHK_FAN_B(P) (P == E0_AUTO_FAN_PIN || P == E1_AUTO_FAN_PIN || P == E2_AUTO_FAN_PIN || P == E3_AUTO_FAN_PIN || P == E4_AUTO_FAN_PIN || P == E5_AUTO_FAN_PIN || P == E6_AUTO_FAN_PIN || P == E7_AUTO_FAN_PIN || P == CHAMBER_AUTO_FAN_PIN)
+// Determine which hardware PWMs are already in use
+#define _PWM_CHK_FAN_B(P) (P == E0_AUTO_FAN_PIN || P == E1_AUTO_FAN_PIN || P == E2_AUTO_FAN_PIN || P == E3_AUTO_FAN_PIN || P == E4_AUTO_FAN_PIN || P == E5_AUTO_FAN_PIN || P == E6_AUTO_FAN_PIN || P == E7_AUTO_FAN_PIN || P == CHAMBER_AUTO_FAN_PIN || P == COOLER_AUTO_FAN_PIN)
 #if PIN_EXISTS(CONTROLLER_FAN)
   #define PWM_CHK_FAN_B(P) (_PWM_CHK_FAN_B(P) || P == CONTROLLER_FAN_PIN)
 #else

Marlin/src/HAL/AVR/inc/SanityCheck.h

@@ -56,3 +56,10 @@
 #if BOTH(HAS_TMC_SW_SERIAL, MONITOR_DRIVER_STATUS)
   #error "MONITOR_DRIVER_STATUS causes performance issues when used with SoftwareSerial-connected drivers. Disable MONITOR_DRIVER_STATUS or use hardware serial to continue."
 #endif
+
+/**
+ * Postmortem debugging
+ */
+#if ENABLED(POSTMORTEM_DEBUGGING)
+  #error "POSTMORTEM_DEBUGGING is not supported on AVR boards."
+#endif

Marlin/src/HAL/AVR/pinsDebug.h

@@ -38,7 +38,7 @@
   // portModeRegister takes a different argument
   #define digitalPinToTimer_DEBUG(p) digitalPinToTimer(p)
   #define digitalPinToBitMask_DEBUG(p) digitalPinToBitMask(p)
-  #define digitalPinToPort_DEBUG(p) digitalPinToPort_Teensy(p)
+  #define digitalPinToPort_DEBUG(p) digitalPinToPort(p)
   #define GET_PINMODE(pin) (*portModeRegister(pin) & digitalPinToBitMask_DEBUG(pin))
 
 #elif AVR_ATmega2560_FAMILY_PLUS_70   // So we can access/display all the pins on boards using more than 70

Marlin/src/HAL/AVR/u8g_com_HAL_AVR_sw_spi.cpp

@@ -62,7 +62,7 @@
 #include "../shared/Marduino.h"
 #include "../shared/Delay.h"
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 uint8_t u8g_bitData, u8g_bitNotData, u8g_bitClock, u8g_bitNotClock;
 volatile uint8_t *u8g_outData, *u8g_outClock;

Marlin/src/HAL/DUE/DebugMonitor.cpp

@@ -1,342 +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 "../../core/macros.h"
-#include "../../core/serial.h"
-
-#include "../shared/backtrace/unwinder.h"
-#include "../shared/backtrace/unwmemaccess.h"
-
-#include <stdarg.h>
-
-// Debug monitor that dumps to the Programming port all status when
-// an exception or WDT timeout happens - And then resets the board
-
-// All the Monitor routines must run with interrupts disabled and
-// under an ISR execution context. That is why we cannot reuse the
-// Serial interrupt routines or any C runtime, as we don't know the
-// state we are when running them
-
-// A SW memory barrier, to ensure GCC does not overoptimize loops
-#define sw_barrier() __asm__ volatile("": : :"memory");
-
-// (re)initialize UART0 as a monitor output to 250000,n,8,1
-static void TXBegin() {
-
-  // Disable UART interrupt in NVIC
-  NVIC_DisableIRQ( UART_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();
-
-  // Disable clock
-  pmc_disable_periph_clk( ID_UART );
-
-  // Configure PMC
-  pmc_enable_periph_clk( ID_UART );
-
-  // Disable PDC channel
-  UART->UART_PTCR = UART_PTCR_RXTDIS | UART_PTCR_TXTDIS;
-
-  // Reset and disable receiver and transmitter
-  UART->UART_CR = UART_CR_RSTRX | UART_CR_RSTTX | UART_CR_RXDIS | UART_CR_TXDIS;
-
-  // Configure mode: 8bit, No parity, 1 bit stop
-  UART->UART_MR = UART_MR_CHMODE_NORMAL | US_MR_CHRL_8_BIT | US_MR_NBSTOP_1_BIT | UART_MR_PAR_NO;
-
-  // Configure baudrate (asynchronous, no oversampling) to BAUDRATE bauds
-  UART->UART_BRGR = (SystemCoreClock / (BAUDRATE << 4));
-
-  // Enable receiver and transmitter
-  UART->UART_CR = UART_CR_RXEN | UART_CR_TXEN;
-}
-
-// Send character through UART with no interrupts
-static void TX(char c) {
-  while (!(UART->UART_SR & UART_SR_TXRDY)) { WDT_Restart(WDT); sw_barrier(); };
-  UART->UART_THR = c;
-}
-
-// Send String through UART
-static void TX(const char* s) {
-  while (*s) TX(*s++);
-}
-
-static void TXDigit(uint32_t d) {
-  if (d < 10) TX((char)(d+'0'));
-  else if (d < 16) TX((char)(d+'A'-10));
-  else TX('?');
-}
-
-// Send Hex number thru UART
-static void TXHex(uint32_t v) {
-  TX("0x");
-  for (uint8_t i = 0; i < 8; i++, v <<= 4)
-    TXDigit((v >> 28) & 0xF);
-}
-
-// Send Decimal number thru UART
-static void TXDec(uint32_t v) {
-  if (!v) {
-    TX('0');
-    return;
-  }
-
-  char nbrs[14];
-  char *p = &nbrs[0];
-  while (v != 0) {
-    *p++ = '0' + (v % 10);
-    v /= 10;
-  }
-  do {
-    p--;
-    TX(*p);
-  } while (p != &nbrs[0]);
-}
-
-// Dump a backtrace entry
-static bool UnwReportOut(void* ctx, const UnwReport* bte) {
-  int* p = (int*)ctx;
-
-  (*p)++;
-  TX('#'); TXDec(*p); TX(" : ");
-  TX(bte->name?bte->name:"unknown"); TX('@'); TXHex(bte->function);
-  TX('+'); TXDec(bte->address - bte->function);
-  TX(" PC:");TXHex(bte->address); TX('\n');
-  return true;
-}
-
-#ifdef UNW_DEBUG
-  void UnwPrintf(const char* format, ...) {
-    char dest[256];
-    va_list argptr;
-    va_start(argptr, format);
-    vsprintf(dest, format, argptr);
-    va_end(argptr);
-    TX(&dest[0]);
-  }
-#endif
-
-/* Table of function pointers for passing to the unwinder */
-static const UnwindCallbacks UnwCallbacks = {
-  UnwReportOut,
-  UnwReadW,
-  UnwReadH,
-  UnwReadB
-  #ifdef UNW_DEBUG
-   , UnwPrintf
-  #endif
-};
-
-/**
- * HardFaultHandler_C:
- * This is called from the HardFault_HandlerAsm with a pointer the Fault stack
- * as the parameter. We can then read the values from the stack and place them
- * into local variables for ease of reading.
- * We then read the various Fault Status and Address Registers to help decode
- * cause of the fault.
- * The function ends with a BKPT instruction to force control back into the debugger
- */
-extern "C"
-void HardFault_HandlerC(unsigned long *sp, unsigned long lr, unsigned long cause) {
-
-  static const char* causestr[] = {
-    "NMI","Hard","Mem","Bus","Usage","Debug","WDT","RSTC"
-  };
-
-  UnwindFrame btf;
-
-  // Dump report to the Programming port (interrupts are DISABLED)
-  TXBegin();
-  TX("\n\n## Software Fault detected ##\n");
-  TX("Cause: "); TX(causestr[cause]); TX('\n');
-
-  TX("R0   : "); TXHex(((unsigned long)sp[0])); TX('\n');
-  TX("R1   : "); TXHex(((unsigned long)sp[1])); TX('\n');
-  TX("R2   : "); TXHex(((unsigned long)sp[2])); TX('\n');
-  TX("R3   : "); TXHex(((unsigned long)sp[3])); TX('\n');
-  TX("R12  : "); TXHex(((unsigned long)sp[4])); TX('\n');
-  TX("LR   : "); TXHex(((unsigned long)sp[5])); TX('\n');
-  TX("PC   : "); TXHex(((unsigned long)sp[6])); TX('\n');
-  TX("PSR  : "); TXHex(((unsigned long)sp[7])); TX('\n');
-
-  // Configurable Fault Status Register
-  // Consists of MMSR, BFSR and UFSR
-  TX("CFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED28)))); TX('\n');
-
-  // Hard Fault Status Register
-  TX("HFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED2C)))); TX('\n');
-
-  // Debug Fault Status Register
-  TX("DFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED30)))); TX('\n');
-
-  // Auxiliary Fault Status Register
-  TX("AFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED3C)))); TX('\n');
-
-  // Read the Fault Address Registers. These may not contain valid values.
-  // Check BFARVALID/MMARVALID to see if they are valid values
-  // MemManage Fault Address Register
-  TX("MMAR : "); TXHex((*((volatile unsigned long *)(0xE000ED34)))); TX('\n');
-
-  // Bus Fault Address Register
-  TX("BFAR : "); TXHex((*((volatile unsigned long *)(0xE000ED38)))); TX('\n');
-
-  TX("ExcLR: "); TXHex(lr); TX('\n');
-  TX("ExcSP: "); TXHex((unsigned long)sp); TX('\n');
-
-  btf.sp = ((unsigned long)sp) + 8*4; // The original stack pointer
-  btf.fp = btf.sp;
-  btf.lr = ((unsigned long)sp[5]);
-  btf.pc = ((unsigned long)sp[6]) | 1; // Force Thumb, as CORTEX only support it
-
-  // Perform a backtrace
-  TX("\nBacktrace:\n\n");
-  int ctr = 0;
-  UnwindStart(&btf, &UnwCallbacks, &ctr);
-
-  // Disable all NVIC interrupts
-  NVIC->ICER[0] = 0xFFFFFFFF;
-  NVIC->ICER[1] = 0xFFFFFFFF;
-
-  // Relocate VTOR table to default position
-  SCB->VTOR = 0;
-
-  // Disable USB
-  otg_disable();
-
-  // Restart watchdog
-  WDT_Restart(WDT);
-
-  // Reset controller
-  NVIC_SystemReset();
-  for (;;) WDT_Restart(WDT);
-}
-
-__attribute__((naked)) void NMI_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#0")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void HardFault_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#1")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void MemManage_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#2")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void BusFault_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#3")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void UsageFault_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#4")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void DebugMon_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#5")
-    A("b HardFault_HandlerC")
-  );
-}
-
-/* This is NOT an exception, it is an interrupt handler - Nevertheless, the framing is the same */
-__attribute__((naked)) void WDT_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#6")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void RSTC_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#7")
-    A("b HardFault_HandlerC")
-  );
-}
-
-#endif // ARDUINO_ARCH_SAM

Marlin/src/HAL/DUE/HAL.cpp

@@ -40,6 +40,8 @@ uint16_t HAL_adc_result;
 // Public functions
 // ------------------------
 
+TERN_(POSTMORTEM_DEBUGGING, extern void install_min_serial());
+
 // HAL initialization task
 void HAL_init() {
   // Initialize the USB stack
@@ -47,6 +49,7 @@ void HAL_init() {
     OUT_WRITE(SDSS, HIGH);  // Try to set SDSS inactive before any other SPI users start up
   #endif
   usb_task_init();
+  TERN_(POSTMORTEM_DEBUGGING, install_min_serial()); // Install the min serial handler
 }
 
 // HAL idle task
@@ -74,6 +77,8 @@ uint8_t HAL_get_reset_source() {
   }
 }
 
+void HAL_reboot() { rstc_start_software_reset(RSTC); }
+
 void _delay_ms(const int delay_ms) {
   // Todo: port for Due?
   delay(delay_ms);
@@ -103,17 +108,17 @@ uint16_t HAL_adc_get_result() {
 }
 
 // Forward the default serial ports
-#if ANY_SERIAL_IS(0)
-  DefaultSerial MSerial(false, Serial);
+#if USING_HW_SERIAL0
+  DefaultSerial1 MSerial0(false, Serial);
 #endif
-#if ANY_SERIAL_IS(1)
-  DefaultSerial1 MSerial1(false, Serial1);
+#if USING_HW_SERIAL1
+  DefaultSerial2 MSerial1(false, Serial1);
 #endif
-#if ANY_SERIAL_IS(2)
-  DefaultSerial2 MSerial2(false, Serial2);
+#if USING_HW_SERIAL2
+  DefaultSerial3 MSerial2(false, Serial2);
 #endif
-#if ANY_SERIAL_IS(3)
-  DefaultSerial3 MSerial3(false, Serial3);
+#if USING_HW_SERIAL3
+  DefaultSerial4 MSerial3(false, Serial3);
 #endif
 
 #endif // ARDUINO_ARCH_SAM

Marlin/src/HAL/DUE/HAL.h

@@ -38,35 +38,43 @@
 
 #include "../../core/serial_hook.h"
 
-typedef ForwardSerial0Type< decltype(Serial) > DefaultSerial;
-typedef ForwardSerial0Type< decltype(Serial1) > DefaultSerial1;
-typedef ForwardSerial0Type< decltype(Serial2) > DefaultSerial2;
-typedef ForwardSerial0Type< decltype(Serial3) > DefaultSerial3;
-extern DefaultSerial MSerial;
-extern DefaultSerial1 MSerial1;
-extern DefaultSerial2 MSerial2;
-extern DefaultSerial3 MSerial3;
+typedef ForwardSerial1Class< decltype(Serial) > DefaultSerial1;
+typedef ForwardSerial1Class< decltype(Serial1) > DefaultSerial2;
+typedef ForwardSerial1Class< decltype(Serial2) > DefaultSerial3;
+typedef ForwardSerial1Class< decltype(Serial3) > DefaultSerial4;
+extern DefaultSerial1 MSerial0;
+extern DefaultSerial2 MSerial1;
+extern DefaultSerial3 MSerial2;
+extern DefaultSerial4 MSerial3;
 
 #define _MSERIAL(X) MSerial##X
 #define MSERIAL(X) _MSERIAL(X)
-#define MSerial0 MSerial
 
-// Define MYSERIAL0/1 before MarlinSerial includes!
 #if SERIAL_PORT == -1 || ENABLED(EMERGENCY_PARSER)
-  #define MYSERIAL0 customizedSerial1
+  #define MYSERIAL1 customizedSerial1
 #elif WITHIN(SERIAL_PORT, 0, 3)
-  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
+  #define MYSERIAL1 MSERIAL(SERIAL_PORT)
 #else
-  #error "The required SERIAL_PORT must be from -1 to 3. Please update your configuration."
+  #error "The required SERIAL_PORT must be from 0 to 3, or -1 for USB Serial."
 #endif
 
 #ifdef SERIAL_PORT_2
   #if SERIAL_PORT_2 == -1 || ENABLED(EMERGENCY_PARSER)
-    #define MYSERIAL1 customizedSerial2
+    #define MYSERIAL2 customizedSerial2
   #elif WITHIN(SERIAL_PORT_2, 0, 3)
-    #define MYSERIAL1 MSERIAL(SERIAL_PORT_2)
+    #define MYSERIAL2 MSERIAL(SERIAL_PORT_2)
   #else
-    #error "SERIAL_PORT_2 must be from -1 to 3. Please update your configuration."
+    #error "SERIAL_PORT_2 must be from 0 to 3, or -1 for USB Serial."
+  #endif
+#endif
+
+#ifdef SERIAL_PORT_3
+  #if SERIAL_PORT_3 == -1 || ENABLED(EMERGENCY_PARSER)
+    #define MYSERIAL3 customizedSerial3
+  #elif WITHIN(SERIAL_PORT_3, 0, 3)
+    #define MYSERIAL3 MSERIAL(SERIAL_PORT_3)
+  #else
+    #error "SERIAL_PORT_3 must be from 0 to 3, or -1 for USB Serial."
   #endif
 #endif
 
@@ -74,17 +82,15 @@ extern DefaultSerial3 MSerial3;
   #if WITHIN(MMU2_SERIAL_PORT, 0, 3)
     #define MMU2_SERIAL MSERIAL(MMU2_SERIAL_PORT)
   #else
-    #error "MMU2_SERIAL_PORT must be from 0 to 3. Please update your configuration."
+    #error "MMU2_SERIAL_PORT must be from 0 to 3."
   #endif
 #endif
 
 #ifdef LCD_SERIAL_PORT
-  #if LCD_SERIAL_PORT == -1
-    #define LCD_SERIAL lcdSerial
-  #elif WITHIN(LCD_SERIAL_PORT, 0, 3)
+  #if WITHIN(LCD_SERIAL_PORT, 0, 3)
     #define LCD_SERIAL MSERIAL(LCD_SERIAL_PORT)
   #else
-    #error "LCD_SERIAL_PORT must be from -1 to 3. Please update your configuration."
+    #error "LCD_SERIAL_PORT must be from 0 to 3."
   #endif
 #endif
 
@@ -114,7 +120,7 @@ void sei();                     // Enable interrupts
 void HAL_clear_reset_source();  // clear reset reason
 uint8_t HAL_get_reset_source(); // get reset reason
 
-inline void HAL_reboot() {}  // reboot the board or restart the bootloader
+void HAL_reboot();
 
 //
 // ADC

Marlin/src/HAL/DUE/HAL_MinSerial.cpp

@@ -0,0 +1,91 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2021 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/MarlinConfigPre.h"
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+
+#include "../shared/HAL_MinSerial.h"
+
+#include <stdarg.h>
+
+static void TXBegin() {
+  // Disable UART interrupt in NVIC
+  NVIC_DisableIRQ( UART_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();
+
+  // Disable clock
+  pmc_disable_periph_clk( ID_UART );
+
+  // Configure PMC
+  pmc_enable_periph_clk( ID_UART );
+
+  // Disable PDC channel
+  UART->UART_PTCR = UART_PTCR_RXTDIS | UART_PTCR_TXTDIS;
+
+  // Reset and disable receiver and transmitter
+  UART->UART_CR = UART_CR_RSTRX | UART_CR_RSTTX | UART_CR_RXDIS | UART_CR_TXDIS;
+
+  // Configure mode: 8bit, No parity, 1 bit stop
+  UART->UART_MR = UART_MR_CHMODE_NORMAL | US_MR_CHRL_8_BIT | US_MR_NBSTOP_1_BIT | UART_MR_PAR_NO;
+
+  // Configure baudrate (asynchronous, no oversampling) to BAUDRATE bauds
+  UART->UART_BRGR = (SystemCoreClock / (BAUDRATE << 4));
+
+  // Enable receiver and transmitter
+  UART->UART_CR = UART_CR_RXEN | UART_CR_TXEN;
+}
+
+// A SW memory barrier, to ensure GCC does not overoptimize loops
+#define sw_barrier() __asm__ volatile("": : :"memory");
+static void TX(char c) {
+  while (!(UART->UART_SR & UART_SR_TXRDY)) { WDT_Restart(WDT); sw_barrier(); };
+  UART->UART_THR = c;
+}
+
+void install_min_serial() {
+  HAL_min_serial_init = &TXBegin;
+  HAL_min_serial_out = &TX;
+}
+
+#if DISABLED(DYNAMIC_VECTORTABLE)
+extern "C" {
+  __attribute__((naked)) void JumpHandler_ASM() {
+    __asm__ __volatile__ (
+      "b CommonHandler_ASM\n"
+    );
+  }
+  void __attribute__((naked, alias("JumpHandler_ASM"))) HardFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) BusFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) UsageFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) MemManage_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) NMI_Handler();
+}
+#endif
+
+#endif // POSTMORTEM_DEBUGGING
+#endif // ARDUINO_ARCH_SAM

Marlin/src/HAL/DUE/HAL_SPI.cpp

@@ -56,8 +56,8 @@
   #pragma GCC optimize (3)
 
   typedef uint8_t (*pfnSpiTransfer)(uint8_t b);
-  typedef void    (*pfnSpiRxBlock)(uint8_t* buf, uint32_t nbyte);
-  typedef void    (*pfnSpiTxBlock)(const uint8_t* buf, uint32_t nbyte);
+  typedef void    (*pfnSpiRxBlock)(uint8_t *buf, uint32_t nbyte);
+  typedef void    (*pfnSpiTxBlock)(const uint8_t *buf, uint32_t nbyte);
 
   /* ---------------- Macros to be able to access definitions from asm */
   #define _PORT(IO) DIO ##  IO ## _WPORT
@@ -240,7 +240,7 @@
   }
 
   // all the others
-  static uint32_t spiDelayCyclesX4 = 4 * (F_CPU) / 1000000; // 4µs => 125khz
+  static uint16_t spiDelayNS = 4000; // 4000ns => 125khz
 
   static uint8_t spiTransferX(uint8_t b) { // using Mode 0
     int bits = 8;
@@ -249,12 +249,12 @@
       b <<= 1; // little setup time
 
       WRITE(SD_SCK_PIN, HIGH);
-      DELAY_CYCLES(spiDelayCyclesX4);
+      DELAY_NS(spiDelayNS);
 
       b |= (READ(SD_MISO_PIN) != 0);
 
       WRITE(SD_SCK_PIN, LOW);
-      DELAY_CYCLES(spiDelayCyclesX4);
+      DELAY_NS(spiDelayNS);
     } while (--bits);
     return b;
   }
@@ -270,7 +270,7 @@
   static pfnSpiTransfer spiTransferTx = (pfnSpiTransfer)spiTransferX;
 
   // Block transfers run at ~8 .. ~10Mhz - Tx version (Rx data discarded)
-  static void spiTxBlock0(const uint8_t* ptr, uint32_t todo) {
+  static void spiTxBlock0(const uint8_t *ptr, uint32_t todo) {
     uint32_t MOSI_PORT_PLUS30 = ((uint32_t) PORT(SD_MOSI_PIN)) + 0x30;  /* SODR of port */
     uint32_t MOSI_MASK = PIN_MASK(SD_MOSI_PIN);
     uint32_t SCK_PORT_PLUS30 = ((uint32_t) PORT(SD_SCK_PIN)) + 0x30;    /* SODR of port */
@@ -349,7 +349,7 @@
     );
   }
 
-  static void spiRxBlock0(uint8_t* ptr, uint32_t todo) {
+  static void spiRxBlock0(uint8_t *ptr, uint32_t todo) {
     uint32_t bin = 0;
     uint32_t work = 0;
     uint32_t BITBAND_MISO_PORT = BITBAND_ADDRESS( ((uint32_t)PORT(SD_MISO_PIN))+0x3C, PIN_SHIFT(SD_MISO_PIN));  /* PDSR of port in bitband area */
@@ -425,19 +425,19 @@
     );
   }
 
-  static void spiTxBlockX(const uint8_t* buf, uint32_t todo) {
+  static void spiTxBlockX(const uint8_t *buf, uint32_t todo) {
     do {
       (void)spiTransferTx(*buf++);
     } while (--todo);
   }
 
-  static void spiRxBlockX(uint8_t* buf, uint32_t todo) {
+  static void spiRxBlockX(uint8_t *buf, uint32_t todo) {
     do {
       *buf++ = spiTransferRx(0xFF);
     } while (--todo);
   }
 
-  // Pointers to generic functions for block tranfers
+  // Pointers to generic functions for block transfers
   static pfnSpiTxBlock spiTxBlock = (pfnSpiTxBlock)spiTxBlockX;
   static pfnSpiRxBlock spiRxBlock = (pfnSpiRxBlock)spiRxBlockX;
 
@@ -463,7 +463,7 @@
     return b;
   }
 
-  void spiRead(uint8_t* buf, uint16_t nbyte) {
+  void spiRead(uint8_t *buf, uint16_t nbyte) {
     if (nbyte) {
       _SS_WRITE(LOW);
       WRITE(SD_MOSI_PIN, HIGH); // Output 1s 1
@@ -478,7 +478,7 @@
     _SS_WRITE(HIGH);
   }
 
-  void spiSendBlock(uint8_t token, const uint8_t* buf) {
+  void spiSendBlock(uint8_t token, const uint8_t *buf) {
     _SS_WRITE(LOW);
     (void)spiTransferTx(token);
     spiTxBlock(buf, 512);
@@ -510,7 +510,7 @@
         spiRxBlock = (pfnSpiRxBlock)spiRxBlockX;
         break;
       default:
-        spiDelayCyclesX4 = ((F_CPU) / 1000000) >> (6 - spiRate) << 2; // spiRate of 2 gives the maximum error with current CPU
+        spiDelayNS = 4000 >> (6 - spiRate); // spiRate of 2 gives the maximum error with current CPU
         spiTransferTx = (pfnSpiTransfer)spiTransferX;
         spiTransferRx = (pfnSpiTransfer)spiTransferX;
         spiTxBlock = (pfnSpiTxBlock)spiTxBlockX;
@@ -645,7 +645,7 @@
     }
 
     // Read from SPI into buffer
-    void spiRead(uint8_t* buf, uint16_t nbyte) {
+    void spiRead(uint8_t *buf, uint16_t nbyte) {
       if (!nbyte) return;
       --nbyte;
       for (int i = 0; i < nbyte; i++) {
@@ -668,7 +668,7 @@
       //DELAY_US(1U);
     }
 
-    void spiSend(const uint8_t* buf, size_t nbyte) {
+    void spiSend(const uint8_t *buf, size_t nbyte) {
       if (!nbyte) return;
       --nbyte;
       for (size_t i = 0; i < nbyte; i++) {
@@ -689,7 +689,7 @@
       FLUSH_RX();
     }
 
-    void spiSend(uint32_t chan, const uint8_t* buf, size_t nbyte) {
+    void spiSend(uint32_t chan, const uint8_t *buf, size_t nbyte) {
       if (!nbyte) return;
       --nbyte;
       for (size_t i = 0; i < nbyte; i++) {
@@ -702,7 +702,7 @@
     }
 
     // Write from buffer to SPI
-    void spiSendBlock(uint8_t token, const uint8_t* buf) {
+    void spiSendBlock(uint8_t token, const uint8_t *buf) {
       SPI0->SPI_TDR = (uint32_t)token | SPI_PCS(SPI_CHAN);
       WHILE_TX(0);
       //WHILE_RX(0);
@@ -801,19 +801,19 @@
 
     uint8_t spiRec() { return (uint8_t)spiTransfer(0xFF); }
 
-    void spiRead(uint8_t* buf, uint16_t nbyte) {
+    void spiRead(uint8_t *buf, uint16_t nbyte) {
       for (int i = 0; i < nbyte; i++)
         buf[i] = spiTransfer(0xFF);
     }
 
     void spiSend(uint8_t data) { spiTransfer(data); }
 
-    void spiSend(const uint8_t* buf, size_t nbyte) {
+    void spiSend(const uint8_t *buf, size_t nbyte) {
       for (uint16_t i = 0; i < nbyte; i++)
         spiTransfer(buf[i]);
     }
 
-    void spiSendBlock(uint8_t token, const uint8_t* buf) {
+    void spiSendBlock(uint8_t token, const uint8_t *buf) {
       spiTransfer(token);
       for (uint16_t i = 0; i < 512; i++)
         spiTransfer(buf[i]);

Marlin/src/HAL/DUE/MarlinSerial.cpp

@@ -476,9 +476,9 @@ void MarlinSerial<Cfg>::flushTX() {
 
 
 // If not using the USB port as serial port
-#if SERIAL_PORT >= 0
+#if defined(SERIAL_PORT) && SERIAL_PORT >= 0
   template class MarlinSerial< MarlinSerialCfg<SERIAL_PORT> >;
-  MSerialT customizedSerial1(MarlinSerialCfg<SERIAL_PORT>::EMERGENCYPARSER);
+  MSerialT1 customizedSerial1(MarlinSerialCfg<SERIAL_PORT>::EMERGENCYPARSER);
 #endif
 
 #if defined(SERIAL_PORT_2) && SERIAL_PORT_2 >= 0
@@ -486,4 +486,9 @@ void MarlinSerial<Cfg>::flushTX() {
   MSerialT2 customizedSerial2(MarlinSerialCfg<SERIAL_PORT_2>::EMERGENCYPARSER);
 #endif
 
+#if defined(SERIAL_PORT_3) && SERIAL_PORT_3 >= 0
+  template class MarlinSerial< MarlinSerialCfg<SERIAL_PORT_3> >;
+  MSerialT3 customizedSerial3(MarlinSerialCfg<SERIAL_PORT_3>::EMERGENCYPARSER);
+#endif
+
 #endif // ARDUINO_ARCH_SAM

Marlin/src/HAL/DUE/MarlinSerial.h

@@ -140,12 +140,17 @@ struct MarlinSerialCfg {
   static constexpr bool MAX_RX_QUEUED     = ENABLED(SERIAL_STATS_MAX_RX_QUEUED);
 };
 
-#if SERIAL_PORT >= 0
-  typedef Serial0Type< MarlinSerial< MarlinSerialCfg<SERIAL_PORT> > > MSerialT;
-  extern MSerialT customizedSerial1;
+#if defined(SERIAL_PORT) && SERIAL_PORT >= 0
+  typedef Serial1Class< MarlinSerial< MarlinSerialCfg<SERIAL_PORT> > > MSerialT1;
+  extern MSerialT1 customizedSerial1;
 #endif
 
 #if defined(SERIAL_PORT_2) && SERIAL_PORT_2 >= 0
-  typedef Serial0Type< MarlinSerial< MarlinSerialCfg<SERIAL_PORT_2> > > MSerialT2;
+  typedef Serial1Class< MarlinSerial< MarlinSerialCfg<SERIAL_PORT_2> > > MSerialT2;
   extern MSerialT2 customizedSerial2;
 #endif
+
+#if defined(SERIAL_PORT_3) && SERIAL_PORT_3 >= 0
+  typedef Serial1Class< MarlinSerial< MarlinSerialCfg<SERIAL_PORT_3> > > MSerialT3;
+  extern MSerialT3 customizedSerial3;
+#endif

Marlin/src/HAL/DUE/MarlinSerialUSB.cpp

@@ -19,13 +19,13 @@
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  *
  */
+#ifdef ARDUINO_ARCH_SAM
 
 /**
  * MarlinSerial_Due.cpp - Hardware serial library for Arduino DUE
  * Copyright (c) 2017 Eduardo José Tagle. All right reserved
  * Based on MarlinSerial for AVR, copyright (c) 2006 Nicholas Zambetti.  All right reserved.
  */
-#ifdef ARDUINO_ARCH_SAM
 
 #include "../../inc/MarlinConfig.h"
 
@@ -65,7 +65,7 @@ int MarlinSerialUSB::peek() {
 
   pending_char = udi_cdc_getc();
 
-  TERN_(EMERGENCY_PARSER, emergency_parser.update(static_cast<MSerialT*>(this)->emergency_state, (char)pending_char));
+  TERN_(EMERGENCY_PARSER, emergency_parser.update(static_cast<MSerialT1*>(this)->emergency_state, (char)pending_char));
 
   return pending_char;
 }
@@ -87,17 +87,16 @@ int MarlinSerialUSB::read() {
 
   int c = udi_cdc_getc();
 
-  TERN_(EMERGENCY_PARSER, emergency_parser.update(static_cast<MSerialT*>(this)->emergency_state, (char)c));
+  TERN_(EMERGENCY_PARSER, emergency_parser.update(static_cast<MSerialT1*>(this)->emergency_state, (char)c));
 
   return c;
 }
 
-bool MarlinSerialUSB::available() {
-    /* If Pending chars */
-  return pending_char >= 0 ||
-    /* or USB CDC enumerated and configured on the PC side and some
-       bytes where sent to us */
-      (usb_task_cdc_isenabled() && udi_cdc_is_rx_ready());
+int MarlinSerialUSB::available() {
+  if (pending_char > 0) return pending_char;
+  return pending_char == 0 ||
+    // or USB CDC enumerated and configured on the PC side and some bytes where sent to us */
+    (usb_task_cdc_isenabled() && udi_cdc_is_rx_ready());
 }
 
 void MarlinSerialUSB::flush() { }
@@ -130,10 +129,13 @@ size_t MarlinSerialUSB::write(const uint8_t c) {
 
 // Preinstantiate
 #if SERIAL_PORT == -1
-  MSerialT customizedSerial1(TERN0(EMERGENCY_PARSER, true));
+  MSerialT1 customizedSerial1(TERN0(EMERGENCY_PARSER, true));
 #endif
 #if SERIAL_PORT_2 == -1
-  MSerialT customizedSerial2(TERN0(EMERGENCY_PARSER, true));
+  MSerialT2 customizedSerial2(TERN0(EMERGENCY_PARSER, true));
+#endif
+#if SERIAL_PORT_3 == -1
+  MSerialT3 customizedSerial3(TERN0(EMERGENCY_PARSER, true));
 #endif
 
 #endif // HAS_USB_SERIAL

Marlin/src/HAL/DUE/MarlinSerialUSB.h

@@ -27,11 +27,9 @@
  */
 
 #include "../../inc/MarlinConfig.h"
-#if HAS_USB_SERIAL
-
-#include <WString.h>
 #include "../../core/serial_hook.h"
 
+#include <WString.h>
 
 struct MarlinSerialUSB {
   void begin(const long);
@@ -39,7 +37,7 @@ struct MarlinSerialUSB {
   int peek();
   int read();
   void flush();
-  bool available();
+  int available();
   size_t write(const uint8_t c);
 
   #if ENABLED(SERIAL_STATS_DROPPED_RX)
@@ -50,14 +48,18 @@ struct MarlinSerialUSB {
     FORCE_INLINE int rxMaxEnqueued() { return 0; }
   #endif
 };
-typedef Serial0Type<MarlinSerialUSB> MSerialT;
 
 #if SERIAL_PORT == -1
-  extern MSerialT customizedSerial1;
+  typedef Serial1Class<MarlinSerialUSB> MSerialT1;
+  extern MSerialT1 customizedSerial1;
 #endif
 
 #if SERIAL_PORT_2 == -1
-  extern MSerialT customizedSerial2;
+  typedef Serial1Class<MarlinSerialUSB> MSerialT2;
+  extern MSerialT2 customizedSerial2;
 #endif
 
-#endif // HAS_USB_SERIAL
+#if SERIAL_PORT_3 == -1
+  typedef Serial1Class<MarlinSerialUSB> MSerialT3;
+  extern MSerialT3 customizedSerial3;
+#endif

Marlin/src/HAL/DUE/dogm/u8g_com_HAL_DUE_shared_hw_spi.cpp

@@ -60,7 +60,7 @@
 
 #if HAS_MARLINUI_U8GLIB
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 #include "../../../MarlinCore.h"
 

Marlin/src/HAL/DUE/dogm/u8g_com_HAL_DUE_st7920_sw_spi.cpp

@@ -62,7 +62,7 @@
 #include "../../../inc/MarlinConfig.h"
 #include "../../shared/Delay.h"
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 #include "u8g_com_HAL_DUE_sw_spi_shared.h"
 

Marlin/src/HAL/DUE/dogm/u8g_com_HAL_DUE_sw_spi.cpp

@@ -64,7 +64,7 @@
 #include "../../shared/Marduino.h"
 #include "../../shared/Delay.h"
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 #if ENABLED(FYSETC_MINI_12864)
   #define SPISEND_SW_DUE u8g_spiSend_sw_DUE_mode_3

Marlin/src/HAL/DUE/dogm/u8g_com_HAL_DUE_sw_spi_shared.cpp

@@ -62,7 +62,7 @@
 #include "../../../inc/MarlinConfig.h"
 #include "../../shared/Delay.h"
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 #include "u8g_com_HAL_DUE_sw_spi_shared.h"
 

Marlin/src/HAL/DUE/dogm/u8g_com_HAL_DUE_sw_spi_shared.h

@@ -23,7 +23,7 @@
 
 #include "../../../inc/MarlinConfigPre.h"
 #include "../../shared/Marduino.h"
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 void u8g_SetPIOutput_DUE(u8g_t *u8g, uint8_t pin_index);
 void u8g_SetPILevel_DUE(u8g_t *u8g, uint8_t pin_index, uint8_t level);

Marlin/src/HAL/DUE/eeprom_flash.cpp

@@ -135,11 +135,11 @@ static uint8_t buffer[256] = {0},   // The RAM buffer to accumulate writes
 #define DEBUG_OUT ENABLED(EE_EMU_DEBUG)
 #include "../../core/debug_out.h"
 
-static void ee_Dump(const int page, const void* data) {
+static void ee_Dump(const int page, const void *data) {
 
   #ifdef EE_EMU_DEBUG
 
-    const uint8_t* c = (const uint8_t*) data;
+    const uint8_t *c = (const uint8_t*) data;
     char buffer[80];
 
     sprintf_P(buffer, PSTR("Page: %d (0x%04x)\n"), page, page);
@@ -181,7 +181,7 @@ static void ee_Dump(const int page, const void* data) {
  * @param data    (pointer to the data buffer)
  */
 __attribute__ ((long_call, section (".ramfunc")))
-static bool ee_PageWrite(uint16_t page, const void* data) {
+static bool ee_PageWrite(uint16_t page, const void *data) {
 
   uint16_t i;
   uint32_t addrflash = uint32_t(getFlashStorage(page));
@@ -293,8 +293,8 @@ static bool ee_PageWrite(uint16_t page, const void* data) {
       ee_Dump(-page, data);
 
       // Calculate count of changed bits
-      uint32_t* p1 = (uint32_t*)addrflash;
-      uint32_t* p2 = (uint32_t*)data;
+      uint32_t *p1 = (uint32_t*)addrflash;
+      uint32_t *p2 = (uint32_t*)data;
       int count = 0;
       for (i =0; i<PageSize >> 2; i++) {
         if (p1[i] != p2[i]) {
@@ -470,7 +470,7 @@ static uint8_t ee_Read(uint32_t address, bool excludeRAMBuffer=false) {
   for (int page = curPage - 1; page >= 0; --page) {
 
     // Get a pointer to the flash page
-    uint8_t* pflash = (uint8_t*)getFlashStorage(page + curGroup * PagesPerGroup);
+    uint8_t *pflash = (uint8_t*)getFlashStorage(page + curGroup * PagesPerGroup);
 
     uint16_t i = 0;
     while (i <= (PageSize - 4)) { /* (PageSize - 4) because otherwise, there is not enough room for data and headers */
@@ -550,7 +550,7 @@ static uint32_t ee_GetAddrRange(uint32_t address, bool excludeRAMBuffer=false) {
   for (int page = curPage - 1; page >= 0; --page) {
 
     // Get a pointer to the flash page
-    uint8_t* pflash = (uint8_t*)getFlashStorage(page + curGroup * PagesPerGroup);
+    uint8_t *pflash = (uint8_t*)getFlashStorage(page + curGroup * PagesPerGroup);
 
     uint16_t i = 0;
     while (i <= (PageSize - 4)) { /* (PageSize - 4) because otherwise, there is not enough room for data and headers */
@@ -589,7 +589,7 @@ static uint32_t ee_GetAddrRange(uint32_t address, bool excludeRAMBuffer=false) {
 }
 
 static bool ee_IsPageClean(int page) {
-  uint32_t* pflash = (uint32_t*) getFlashStorage(page);
+  uint32_t *pflash = (uint32_t*) getFlashStorage(page);
   for (uint16_t i = 0; i < (PageSize >> 2); ++i)
     if (*pflash++ != 0xFFFFFFFF) return false;
   return true;
@@ -599,7 +599,7 @@ static bool ee_Flush(uint32_t overrideAddress = 0xFFFFFFFF, uint8_t overrideData
 
   // Check if RAM buffer has something to be written
   bool isEmpty = true;
-  uint32_t* p = (uint32_t*) &buffer[0];
+  uint32_t *p = (uint32_t*) &buffer[0];
   for (uint16_t j = 0; j < (PageSize >> 2); j++) {
     if (*p++ != 0xFFFFFFFF) {
       isEmpty = false;
@@ -976,14 +976,13 @@ bool PersistentStore::access_start()  { ee_Init();  return true; }
 bool PersistentStore::access_finish() { ee_Flush(); return true; }
 
 bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  uint16_t written = 0;
   while (size--) {
     uint8_t * const p = (uint8_t * const)pos;
     uint8_t v = *value;
-    // EEPROM has only ~100,000 write cycles,
-    // so only write bytes that have changed!
-    if (v != ee_Read(uint32_t(p))) {
+    if (v != ee_Read(uint32_t(p))) { // EEPROM has only ~100,000 write cycles, so only write bytes that have changed!
       ee_Write(uint32_t(p), v);
-      delay(2);
+      if (++written & 0x7F) delay(2); else safe_delay(2); // Avoid triggering watchdog during long EEPROM writes
       if (ee_Read(uint32_t(p)) != v) {
         SERIAL_ECHO_MSG(STR_ERR_EEPROM_WRITE);
         return true;

Marlin/src/HAL/DUE/eeprom_wired.cpp

@@ -42,14 +42,13 @@ bool PersistentStore::access_start()  { eeprom_init(); return true; }
 bool PersistentStore::access_finish() { return true; }
 
 bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  uint16_t written = 0;
   while (size--) {
     uint8_t * const p = (uint8_t * const)pos;
     uint8_t v = *value;
-    // EEPROM has only ~100,000 write cycles,
-    // so only write bytes that have changed!
-    if (v != eeprom_read_byte(p)) {
+    if (v != eeprom_read_byte(p)) { // EEPROM has only ~100,000 write cycles, so only write bytes that have changed!
       eeprom_write_byte(p, v);
-      delay(2);
+      if (++written & 0x7F) delay(2); else safe_delay(2); // Avoid triggering watchdog during long EEPROM writes
       if (eeprom_read_byte(p) != v) {
         SERIAL_ECHO_MSG(STR_ERR_EEPROM_WRITE);
         return true;

Marlin/src/HAL/DUE/endstop_interrupts.h

@@ -64,4 +64,10 @@ void setup_endstop_interrupts() {
   TERN_(HAS_Z4_MAX, _ATTACH(Z4_MAX_PIN));
   TERN_(HAS_Z4_MIN, _ATTACH(Z4_MIN_PIN));
   TERN_(HAS_Z_MIN_PROBE_PIN, _ATTACH(Z_MIN_PROBE_PIN));
+  TERN_(HAS_I_MAX, _ATTACH(I_MAX_PIN));
+  TERN_(HAS_I_MIN, _ATTACH(I_MIN_PIN));
+  TERN_(HAS_J_MAX, _ATTACH(J_MAX_PIN));
+  TERN_(HAS_J_MIN, _ATTACH(J_MIN_PIN));
+  TERN_(HAS_K_MAX, _ATTACH(K_MAX_PIN));
+  TERN_(HAS_K_MIN, _ATTACH(K_MIN_PIN));
 }

Marlin/src/HAL/DUE/fastio.h

@@ -33,7 +33,7 @@
  * For ARDUINO_ARCH_SAM
  * Note the code here was specifically crafted by disassembling what GCC produces
  * out of it, so GCC is able to optimize it out as much as possible to the least
- * amount of instructions. Be very carefull if you modify them, as "clean code"
+ * amount of instructions. Be very careful if you modify them, as "clean code"
  * leads to less efficient compiled code!!
  */
 

Marlin/src/HAL/DUE/inc/SanityCheck.h

@@ -57,5 +57,5 @@
 #endif
 
 #if HAS_TMC_SW_SERIAL
-  #error "TMC220x Software Serial is not supported on this platform."
+  #error "TMC220x Software Serial is not supported on the DUE platform."
 #endif

Marlin/src/HAL/DUE/usb/arduino_due_x.h

@@ -71,7 +71,7 @@
 /* ------------------------------------------------------------------------ */
 
 /**
- * \page arduino_due_x_board_info "Arduino Due/X - Board informations"
+ * \page arduino_due_x_board_info "Arduino Due/X - Board information"
  * This page lists several definition related to the board description.
  *
  */

Marlin/src/HAL/DUE/usb/sd_mmc_spi_mem.cpp

@@ -32,7 +32,7 @@ Ctrl_status sd_mmc_spi_test_unit_ready() {
 Ctrl_status sd_mmc_spi_read_capacity(uint32_t *nb_sector) {
   if (!IS_SD_INSERTED() || IS_SD_PRINTING() || IS_SD_FILE_OPEN() || !card.isMounted())
     return CTRL_NO_PRESENT;
-  *nb_sector = card.getSd2Card().cardSize() - 1;
+  *nb_sector = card.diskIODriver()->cardSize() - 1;
   return CTRL_GOOD;
 }
 
@@ -74,24 +74,24 @@ Ctrl_status sd_mmc_spi_usb_read_10(uint32_t addr, uint16_t nb_sector) {
   #endif
 
   // Start reading
-  if (!card.getSd2Card().readStart(addr))
+  if (!card.diskIODriver()->readStart(addr))
     return CTRL_FAIL;
 
   // For each specified sector
   while (nb_sector--) {
 
     // Read a sector
-    card.getSd2Card().readData(sector_buf);
+    card.diskIODriver()->readData(sector_buf);
 
     // RAM -> USB
     if (!udi_msc_trans_block(true, sector_buf, SD_MMC_BLOCK_SIZE, nullptr)) {
-      card.getSd2Card().readStop();
+      card.diskIODriver()->readStop();
       return CTRL_FAIL;
     }
   }
 
   // Stop reading
-  card.getSd2Card().readStop();
+  card.diskIODriver()->readStop();
 
   // Done
   return CTRL_GOOD;
@@ -113,7 +113,7 @@ Ctrl_status sd_mmc_spi_usb_write_10(uint32_t addr, uint16_t nb_sector) {
   }
   #endif
 
-  if (!card.getSd2Card().writeStart(addr, nb_sector))
+  if (!card.diskIODriver()->writeStart(addr, nb_sector))
     return CTRL_FAIL;
 
   // For each specified sector
@@ -121,16 +121,16 @@ Ctrl_status sd_mmc_spi_usb_write_10(uint32_t addr, uint16_t nb_sector) {
 
     // USB -> RAM
     if (!udi_msc_trans_block(false, sector_buf, SD_MMC_BLOCK_SIZE, nullptr)) {
-      card.getSd2Card().writeStop();
+      card.diskIODriver()->writeStop();
       return CTRL_FAIL;
     }
 
     // Write a sector
-    card.getSd2Card().writeData(sector_buf);
+    card.diskIODriver()->writeData(sector_buf);
   }
 
   // Stop writing
-  card.getSd2Card().writeStop();
+  card.diskIODriver()->writeStop();
 
   // Done
   return CTRL_GOOD;

Marlin/src/HAL/DUE/usb/sd_mmc_spi_mem.h

@@ -74,7 +74,7 @@
 #define   SD_MMC_REMOVING      2
 
 
-//---- CONTROL FONCTIONS ----
+//---- CONTROL FUNCTIONS ----
 //!
 //! @brief This function initializes the hw/sw resources required to drive the SD_MMC_SPI.
 //!/
@@ -134,7 +134,7 @@ extern bool           sd_mmc_spi_wr_protect(void);
 extern bool           sd_mmc_spi_removal(void);
 
 
-//---- ACCESS DATA FONCTIONS ----
+//---- ACCESS DATA FUNCTIONS ----
 
 #if ACCESS_USB == true
 // Standard functions for open in read/write mode the device

Marlin/src/HAL/DUE/usb/udd.h

@@ -90,7 +90,7 @@ typedef struct {
 	//! This buffer must be word align for DATA IN phase (use prefix COMPILER_WORD_ALIGNED for buffer)
 	uint8_t *payload;
 
-	//! Size of buffer to send or fill, and content the number of byte transfered
+	//! Size of buffer to send or fill, and content the number of byte transferred
 	uint16_t payload_size;
 
 	//! Callback called after reception of ZLP from setup request
@@ -132,10 +132,10 @@ typedef void (*udd_callback_halt_cleared_t)(void);
  *
  * \param status     UDD_EP_TRANSFER_OK, if transfer is complete
  * \param status     UDD_EP_TRANSFER_ABORT, if transfer is aborted
- * \param n          number of data transfered
+ * \param n          number of data transferred
  */
 typedef void (*udd_callback_trans_t) (udd_ep_status_t status,
-		iram_size_t nb_transfered, udd_ep_id_t ep);
+		iram_size_t nb_transferred, udd_ep_id_t ep);
 
 /**
  * \brief Authorizes the VBUS event
@@ -303,7 +303,7 @@ bool udd_ep_wait_stall_clear(udd_ep_id_t ep,
  * The driver uses a specific DMA USB to transfer data
  * from internal RAM to endpoint, if this one is available.
  * When the transfer is finished or aborted (stall, reset, ...), the \a callback is called.
- * The \a callback returns the transfer status and eventually the number of byte transfered.
+ * The \a callback returns the transfer status and eventually the number of byte transferred.
  * Note: The control endpoint is not authorized.
  *
  * \param ep            The ID of the endpoint to use

Marlin/src/HAL/DUE/usb/udi_cdc.c

@@ -162,7 +162,7 @@ static void udi_cdc_ctrl_state_notify(uint8_t port, udd_ep_id_t ep);
  *
  * \param status     UDD_EP_TRANSFER_OK, if transfer finished
  * \param status     UDD_EP_TRANSFER_ABORT, if transfer aborted
- * \param n          number of data transfered
+ * \param n          number of data transferred
  */
 static void udi_cdc_serial_state_msg_sent(udd_ep_status_t status, iram_size_t n, udd_ep_id_t ep);
 
@@ -200,7 +200,7 @@ static void udi_cdc_data_received(udd_ep_status_t status, iram_size_t n, udd_ep_
  *
  * \param status     UDD_EP_TRANSFER_OK, if transfer finished
  * \param status     UDD_EP_TRANSFER_ABORT, if transfer aborted
- * \param n          number of data transfered
+ * \param n          number of data transferred
  */
 static void udi_cdc_data_sent(udd_ep_status_t status, iram_size_t n, udd_ep_id_t ep);
 

Marlin/src/HAL/DUE/usb/udi_cdc.h

@@ -675,11 +675,11 @@ iram_size_t udi_cdc_multi_write_buf(uint8_t port, const void* buf, iram_size_t s
  *   - \code // Waits and gets a value on CDC line
 	int udi_cdc_getc(void);
 	// Reads a RAM buffer on CDC line
-	iram_size_t udi_cdc_read_buf(int* buf, iram_size_t size);
+	iram_size_t udi_cdc_read_buf(int *buf, iram_size_t size);
 	// Puts a byte on CDC line
 	int udi_cdc_putc(int value);
 	// Writes a RAM buffer on CDC line
-	iram_size_t udi_cdc_write_buf(const int* buf, iram_size_t size); \endcode
+	iram_size_t udi_cdc_write_buf(const int *buf, iram_size_t size); \endcode
  *
  * \section udi_cdc_use_cases Advanced use cases
  * For more advanced use of the UDI CDC module, see the following use cases:

Marlin/src/HAL/DUE/usb/udi_cdc_conf.h

@@ -106,7 +106,7 @@ extern "C" {
  */
 //@{
 #  if UDI_CDC_PORT_NB > 2
-#    error USBB, UDP, UDPHS and UOTGHS interfaces have not enought endpoints.
+#    error USBB, UDP, UDPHS and UOTGHS interfaces have not enough endpoints.
 #  endif
 #define  UDI_CDC_DATA_EP_IN_0          (1 | USB_EP_DIR_IN)  // TX
 #define  UDI_CDC_DATA_EP_OUT_0         (2 | USB_EP_DIR_OUT) // RX

Marlin/src/HAL/DUE/usb/udi_msc.c

@@ -173,7 +173,7 @@ static void udi_msc_cbw_wait(void);
  *
  * \param status       UDD_EP_TRANSFER_OK, if transfer is finished
  * \param status       UDD_EP_TRANSFER_ABORT, if transfer is aborted
- * \param nb_received  number of data transfered
+ * \param nb_received  number of data transferred
  */
 static void udi_msc_cbw_received(udd_ep_status_t status,
     iram_size_t nb_received, udd_ep_id_t ep);
@@ -211,7 +211,7 @@ static void udi_msc_data_send(uint8_t * buffer, uint8_t buf_size);
  *
  * \param status     UDD_EP_TRANSFER_OK, if transfer finish
  * \param status     UDD_EP_TRANSFER_ABORT, if transfer aborted
- * \param nb_sent    number of data transfered
+ * \param nb_sent    number of data transferred
  */
 static void udi_msc_data_sent(udd_ep_status_t status, iram_size_t nb_sent,
     udd_ep_id_t ep);
@@ -244,7 +244,7 @@ void udi_msc_csw_send(void);
  *
  * \param status     UDD_EP_TRANSFER_OK, if transfer is finished
  * \param status     UDD_EP_TRANSFER_ABORT, if transfer is aborted
- * \param nb_sent    number of data transfered
+ * \param nb_sent    number of data transferred
  */
 static void udi_msc_csw_sent(udd_ep_status_t status, iram_size_t nb_sent,
     udd_ep_id_t ep);
@@ -463,7 +463,7 @@ uint8_t udi_msc_getsetting(void)
 static void udi_msc_cbw_invalid(void)
 {
   if (!udi_msc_b_cbw_invalid)
-    return; // Don't re-stall endpoint if error reseted by setup
+    return; // Don't re-stall endpoint if error reset by setup
   udd_ep_set_halt(UDI_MSC_EP_OUT);
   // If stall cleared then re-stall it. Only Setup MSC Reset can clear it
   udd_ep_wait_stall_clear(UDI_MSC_EP_OUT, udi_msc_cbw_invalid);
@@ -472,7 +472,7 @@ static void udi_msc_cbw_invalid(void)
 static void udi_msc_csw_invalid(void)
 {
   if (!udi_msc_b_cbw_invalid)
-    return; // Don't re-stall endpoint if error reseted by setup
+    return; // Don't re-stall endpoint if error reset by setup
   udd_ep_set_halt(UDI_MSC_EP_IN);
   // If stall cleared then re-stall it. Only Setup MSC Reset can clear it
   udd_ep_wait_stall_clear(UDI_MSC_EP_IN, udi_msc_csw_invalid);

Marlin/src/HAL/DUE/usb/uotghs_device_due.c

@@ -325,7 +325,7 @@ static void udd_sleep_mode(bool b_idle)
 /**
  * \name Control endpoint low level management routine.
  *
- * This function performs control endpoint mangement.
+ * This function performs control endpoint management.
  * It handle the SETUP/DATA/HANDSHAKE phases of a control transaction.
  */
 //@{
@@ -397,9 +397,9 @@ static void udd_ctrl_endofrequest(void);
 /**
  * \brief Main interrupt routine for control endpoint
  *
- * This switchs control endpoint events to correct sub function.
+ * This switches control endpoint events to correct sub function.
  *
- * \return \c 1 if an event about control endpoint is occured, otherwise \c 0.
+ * \return \c 1 if an event about control endpoint is occurred, otherwise \c 0.
  */
 static bool udd_ctrl_interrupt(void);
 
@@ -410,7 +410,7 @@ static bool udd_ctrl_interrupt(void);
  * \name Management of bulk/interrupt/isochronous endpoints
  *
  * The UDD manages the data transfer on endpoints:
- * - Start data tranfer on endpoint with USB Device DMA
+ * - Start data transfer on endpoint with USB Device DMA
  * - Send a ZLP packet if requested
  * - Call callback registered to signal end of transfer
  * The transfer abort and stall feature are supported.
@@ -431,7 +431,7 @@ typedef struct {
 	uint8_t *buf;
 	//! Size of buffer to send or fill
 	iram_size_t buf_size;
-	//!< Size of data transfered
+	//!< Size of data transferred
 	iram_size_t buf_cnt;
 	//!< Size of data loaded (or prepared for DMA) last time
 	iram_size_t buf_load;
@@ -486,7 +486,7 @@ static void udd_ep_finish_job(udd_ep_job_t * ptr_job, bool b_abort, uint8_t ep_n
 
 #ifdef UDD_EP_DMA_SUPPORTED
 	/**
-	 * \brief Start the next transfer if necessary or complet the job associated.
+	 * \brief Start the next transfer if necessary or complete the job associated.
 	 *
 	 * \param ep endpoint number without direction flag
 	 */
@@ -496,9 +496,9 @@ static void udd_ep_finish_job(udd_ep_job_t * ptr_job, bool b_abort, uint8_t ep_n
 /**
  * \brief Main interrupt routine for bulk/interrupt/isochronous endpoints
  *
- * This switchs endpoint events to correct sub function.
+ * This switches endpoint events to correct sub function.
  *
- * \return \c 1 if an event about bulk/interrupt/isochronous endpoints has occured, otherwise \c 0.
+ * \return \c 1 if an event about bulk/interrupt/isochronous endpoints has occurred, otherwise \c 0.
  */
 static bool udd_ep_interrupt(void);
 
@@ -520,7 +520,7 @@ static bool udd_ep_interrupt(void);
  *
  * Note:
  * Here, the global interrupt mask is not clear when an USB interrupt is enabled
- * because this one can not be occured during the USB ISR (=during INTX is masked).
+ * because this one can not be occurred during the USB ISR (=during INTX is masked).
  * See Technical reference $3.8.3 Masking interrupt requests in peripheral modules.
  */
 #ifdef UHD_ENABLE
@@ -787,7 +787,7 @@ void udd_attach(void)
 	udd_sleep_mode(true);
 	otg_unfreeze_clock();
 
-	// This section of clock check can be improved with a chek of
+	// This section of clock check can be improved with a check of
 	// USB clock source via sysclk()
 	// Check USB clock because the source can be a PLL
 	while (!Is_otg_clock_usable());
@@ -803,7 +803,7 @@ void udd_attach(void)
 #ifdef USB_DEVICE_HS_SUPPORT
 	udd_enable_msof_interrupt();
 #endif
-	// Reset following interupts flag
+	// Reset following interrupts flag
 	udd_ack_reset();
 	udd_ack_sof();
 	udd_ack_msof();
@@ -902,7 +902,7 @@ bool udd_ep_alloc(udd_ep_id_t ep, uint8_t bmAttributes,
 	}
 	dbg_print("alloc(%x, %d) ", ep, MaxEndpointSize);
 
-	// Bank choise
+	// Bank choice
 	switch (bmAttributes & USB_EP_TYPE_MASK) {
 	case USB_EP_TYPE_ISOCHRONOUS:
 		nb_bank = UDD_ISOCHRONOUS_NB_BANK(ep);
@@ -1228,7 +1228,7 @@ bool udd_ep_wait_stall_clear(udd_ep_id_t ep,
 
 	if (Is_udd_endpoint_stall_requested(ep)
 			|| ptr_job->stall_requested) {
-		// Endpoint halted then registes the callback
+		// Endpoint halted then registers the callback
 		ptr_job->busy = true;
 		ptr_job->call_nohalt = callback;
 	} else {
@@ -1386,7 +1386,7 @@ static void udd_ctrl_setup_received(void)
 
 	// Decode setup request
 	if (udc_process_setup() == false) {
-		// Setup request unknow then stall it
+		// Setup request unknown then stall it
 		udd_ctrl_stall_data();
 		udd_ack_setup_received(0);
 		return;
@@ -1447,7 +1447,7 @@ static void udd_ctrl_in_sent(void)
 		udd_ctrl_prev_payload_buf_cnt += udd_ctrl_payload_buf_cnt;
 		if ((udd_g_ctrlreq.req.wLength == udd_ctrl_prev_payload_buf_cnt)
 					|| b_shortpacket) {
-			// All data requested are transfered or a short packet has been sent
+			// All data requested are transferred or a short packet has been sent
 			// then it is the end of data phase.
 			// Generate an OUT ZLP for handshake phase.
 			udd_ctrl_send_zlp_out();
@@ -1516,7 +1516,7 @@ static void udd_ctrl_out_received(void)
 			// End of SETUP request:
 			// - Data IN Phase aborted,
 			// - or last Data IN Phase hidden by ZLP OUT sending quiclky,
-			// - or ZLP OUT received normaly.
+			// - or ZLP OUT received normally.
 			udd_ctrl_endofrequest();
 		} else {
 			// Protocol error during SETUP request
@@ -1544,7 +1544,7 @@ static void udd_ctrl_out_received(void)
 					(udd_ctrl_prev_payload_buf_cnt +
 							udd_ctrl_payload_buf_cnt))) {
 		// End of reception because it is a short packet
-		// Before send ZLP, call intermediat calback
+		// Before send ZLP, call intermediate callback
 		// in case of data receiv generate a stall
 		udd_g_ctrlreq.payload_size = udd_ctrl_payload_buf_cnt;
 		if (NULL != udd_g_ctrlreq.over_under_run) {
@@ -1565,7 +1565,7 @@ static void udd_ctrl_out_received(void)
 	if (udd_g_ctrlreq.payload_size == udd_ctrl_payload_buf_cnt) {
 		// Overrun then request a new payload buffer
 		if (!udd_g_ctrlreq.over_under_run) {
-			// No callback availabled to request a new payload buffer
+			// No callback available to request a new payload buffer
 			udd_ctrl_stall_data();
 			// Ack reception of OUT to replace NAK by a STALL
 			udd_ack_out_received(0);
@@ -1805,7 +1805,7 @@ static void udd_ep_trans_done(udd_ep_id_t ep)
 			// transfer size of UDD_ENDPOINT_MAX_TRANS Bytes
 			next_trans = UDD_ENDPOINT_MAX_TRANS;
 
-			// Set 0 to tranfer the maximum
+			// Set 0 to transfer the maximum
 			udd_dma_ctrl = UOTGHS_DEVDMACONTROL_BUFF_LENGTH(0);
 		} else {
 			udd_dma_ctrl = UOTGHS_DEVDMACONTROL_BUFF_LENGTH(next_trans);
@@ -1850,7 +1850,7 @@ static void udd_ep_trans_done(udd_ep_id_t ep)
 		}
 		cpu_irq_restore(flags);
 
-		// Here a ZLP has been recieved
+		// Here a ZLP has been received
 		// and the DMA transfer must be not started.
 		// It is the end of transfer
 		ptr_job->buf_size = ptr_job->buf_cnt;
@@ -1991,13 +1991,13 @@ static bool udd_ep_interrupt(void)
 			}
 			dbg_print("dma%x: ", ep);
 			udd_disable_endpoint_dma_interrupt(ep);
-			// Save number of data no transfered
+			// Save number of data no transferred
 			nb_remaining = (udd_endpoint_dma_get_status(ep) &
 					UOTGHS_DEVDMASTATUS_BUFF_COUNT_Msk)
 					>> UOTGHS_DEVDMASTATUS_BUFF_COUNT_Pos;
 			if (nb_remaining) {
 				// Transfer no complete (short packet or ZLP) then:
-				// Update number of data transfered
+				// Update number of data transferred
 				ptr_job->buf_cnt -= nb_remaining;
 				// Set transfer complete to stop the transfer
 				ptr_job->buf_size = ptr_job->buf_cnt;
@@ -2056,7 +2056,7 @@ static bool udd_ep_interrupt(void)
 				udd_disable_endpoint_interrupt(ep);
 
 				Assert(ptr_job->stall_requested);
-				// A stall has been requested during backgound transfer
+				// A stall has been requested during background transfer
 				ptr_job->stall_requested = false;
 				udd_disable_endpoint_bank_autoswitch(ep);
 				udd_enable_stall_handshake(ep);

Marlin/src/HAL/DUE/usb/usb_protocol_msc.h

@@ -130,7 +130,7 @@ struct usb_msc_cbw {
 struct usb_msc_csw {
 	le32_t dCSWSignature;	//!< Must contain 'USBS'
 	le32_t dCSWTag;	//!< Same as dCBWTag
-	le32_t dCSWDataResidue;	//!< Number of bytes not transfered
+	le32_t dCSWDataResidue;	//!< Number of bytes not transferred
 	uint8_t bCSWStatus;	//!< Status code
 };
 

Marlin/src/HAL/DUE/usb/usb_task.c

@@ -264,7 +264,7 @@ bool usb_task_extra_string(void) {
 ** Handle device requests that the ASF stack doesn't
 */
 bool usb_task_other_requests(void) {
-  uint8_t* ptr = 0;
+  uint8_t *ptr = 0;
   uint16_t size = 0;
 
   if (Udd_setup_type() == USB_REQ_TYPE_VENDOR) {
@@ -322,7 +322,7 @@ void usb_task_init(void) {
       char *sptr;
 
       // Patch in the filament diameter
-      sprintf_P(diam, PSTR("%d"), (int)((DEFAULT_NOMINAL_FILAMENT_DIA) * 1000.0));
+      itoa((int)((DEFAULT_NOMINAL_FILAMENT_DIA) * 1000), diam, 10);
 
       // And copy it to the proper place, expanding it to unicode
       sptr = &diam[0];

Marlin/src/HAL/ESP32/FlushableHardwareSerial.cpp

@@ -20,11 +20,10 @@
  *
  */
 
-#include "FlushableHardwareSerial.h"
-
 #ifdef ARDUINO_ARCH_ESP32
 
+#include "FlushableHardwareSerial.h"
 
-Serial0Type<FlushableHardwareSerial> flushableSerial(false, 0);
+Serial1Class<FlushableHardwareSerial> flushableSerial(false, 0);
 
-#endif // ARDUINO_ARCH_ESP32
+#endif

Marlin/src/HAL/ESP32/FlushableHardwareSerial.h

@@ -21,9 +21,9 @@
  */
 #pragma once
 
-#ifdef ARDUINO_ARCH_ESP32
-
 #include <HardwareSerial.h>
+
+#include "../shared/Marduino.h"
 #include "../../core/serial_hook.h"
 
 class FlushableHardwareSerial : public HardwareSerial {
@@ -31,6 +31,4 @@ public:
   FlushableHardwareSerial(int uart_nr) : HardwareSerial(uart_nr) {}
 };
 
-extern Serial0Type<FlushableHardwareSerial> flushableSerial;
-
-#endif // ARDUINO_ARCH_ESP32
+extern Serial1Class<FlushableHardwareSerial> flushableSerial;

Marlin/src/HAL/ESP32/HAL.cpp

@@ -41,7 +41,7 @@
 #endif
 
 #if ENABLED(ESP3D_WIFISUPPORT)
-  DefaultSerial MSerial(false, Serial2Socket);
+  DefaultSerial1 MSerial0(false, Serial2Socket);
 #endif
 
 // ------------------------
@@ -141,6 +141,8 @@ void HAL_clear_reset_source() { }
 
 uint8_t HAL_get_reset_source() { return rtc_get_reset_reason(1); }
 
+void HAL_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
@@ -185,6 +187,7 @@ void HAL_adc_init() {
   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_(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.

Marlin/src/HAL/ESP32/HAL.h

@@ -51,15 +51,15 @@
 
 extern portMUX_TYPE spinlock;
 
-#define MYSERIAL0 flushableSerial
+#define MYSERIAL1 flushableSerial
 
 #if EITHER(WIFISUPPORT, ESP3D_WIFISUPPORT)
   #if ENABLED(ESP3D_WIFISUPPORT)
-    typedef ForwardSerial0Type< decltype(Serial2Socket) > DefaultSerial;
-    extern DefaultSerial MSerial;
-    #define MYSERIAL1 MSerial
+    typedef ForwardSerial1Class< decltype(Serial2Socket) > DefaultSerial1;
+    extern DefaultSerial1 MSerial0;
+    #define MYSERIAL2 MSerial0
   #else
-    #define MYSERIAL1 webSocketSerial
+    #define MYSERIAL2 webSocketSerial
   #endif
 #endif
 
@@ -101,7 +101,7 @@ void HAL_clear_reset_source();
 // reset reason
 uint8_t HAL_get_reset_source();
 
-inline void HAL_reboot() {}  // reboot the board or restart the bootloader
+void HAL_reboot();
 
 void _delay_ms(int delay);
 

Marlin/src/HAL/ESP32/HAL_SPI.cpp

@@ -85,7 +85,7 @@ uint8_t spiRec() {
   return returnByte;
 }
 
-void spiRead(uint8_t* buf, uint16_t nbyte) {
+void spiRead(uint8_t *buf, uint16_t nbyte) {
   SPI.beginTransaction(spiConfig);
   SPI.transferBytes(0, buf, nbyte);
   SPI.endTransaction();
@@ -97,7 +97,7 @@ void spiSend(uint8_t b) {
   SPI.endTransaction();
 }
 
-void spiSendBlock(uint8_t token, const uint8_t* buf) {
+void spiSendBlock(uint8_t token, const uint8_t *buf) {
   SPI.beginTransaction(spiConfig);
   SPI.transfer(token);
   SPI.writeBytes(const_cast<uint8_t*>(buf), 512);

Marlin/src/HAL/ESP32/WebSocketSerial.cpp

@@ -29,7 +29,7 @@
 #include "wifi.h"
 #include <ESPAsyncWebServer.h>
 
-MSerialT webSocketSerial(false);
+MSerialWebSocketT webSocketSerial(false);
 AsyncWebSocket ws("/ws"); // TODO Move inside the class.
 
 // RingBuffer impl
@@ -137,7 +137,7 @@ size_t WebSocketSerial::write(const uint8_t c) {
   return ret;
 }
 
-size_t WebSocketSerial::write(const uint8_t* buffer, size_t size) {
+size_t WebSocketSerial::write(const uint8_t *buffer, size_t size) {
   size_t written = 0;
   for (size_t i = 0; i < size; i++)
     written += write(buffer[i]);

Marlin/src/HAL/ESP32/WebSocketSerial.h

@@ -54,7 +54,7 @@ public:
   ring_buffer_pos_t read(uint8_t *buffer);
   void flush();
   ring_buffer_pos_t write(const uint8_t c);
-  ring_buffer_pos_t write(const uint8_t* buffer, ring_buffer_pos_t size);
+  ring_buffer_pos_t write(const uint8_t *buffer, ring_buffer_pos_t size);
 };
 
 class WebSocketSerial: public Stream {
@@ -70,7 +70,7 @@ public:
   int read();
   void flush();
   size_t write(const uint8_t c);
-  size_t write(const uint8_t* buffer, size_t size);
+  size_t write(const uint8_t *buffer, size_t size);
 
   #if ENABLED(SERIAL_STATS_DROPPED_RX)
     FORCE_INLINE uint32_t dropped() { return 0; }
@@ -81,5 +81,5 @@ public:
   #endif
 };
 
-typedef Serial0Type<WebSocketSerial> MSerialT;
-extern MSerialT webSocketSerial;
+typedef Serial1Class<WebSocketSerial> MSerialWebSocketT;
+extern MSerialWebSocketT webSocketSerial;

Marlin/src/HAL/ESP32/endstop_interrupts.h

@@ -59,4 +59,10 @@ void setup_endstop_interrupts() {
   TERN_(HAS_Z4_MAX, _ATTACH(Z4_MAX_PIN));
   TERN_(HAS_Z4_MIN, _ATTACH(Z4_MIN_PIN));
   TERN_(HAS_Z_MIN_PROBE_PIN, _ATTACH(Z_MIN_PROBE_PIN));
+  TERN_(HAS_I_MAX, _ATTACH(I_MAX_PIN));
+  TERN_(HAS_I_MIN, _ATTACH(I_MIN_PIN));
+  TERN_(HAS_J_MAX, _ATTACH(J_MAX_PIN));
+  TERN_(HAS_J_MIN, _ATTACH(J_MIN_PIN));
+  TERN_(HAS_K_MAX, _ATTACH(K_MAX_PIN));
+  TERN_(HAS_K_MIN, _ATTACH(K_MIN_PIN));
 }

Marlin/src/HAL/ESP32/i2s.cpp

@@ -139,7 +139,7 @@ static void IRAM_ATTR i2s_intr_handler_default(void *arg) {
   I2S0.int_clr.val = I2S0.int_st.val; //clear pending interrupt
 }
 
-void stepperTask(void* parameter) {
+void stepperTask(void *parameter) {
   uint32_t remaining = 0;
 
   while (1) {

Marlin/src/HAL/ESP32/inc/SanityCheck.h

@@ -30,9 +30,13 @@
 #endif
 
 #if HAS_TMC_SW_SERIAL
-  #error "TMC220x Software Serial is not supported on this platform."
+  #error "TMC220x Software Serial is not supported on ESP32."
 #endif
 
 #if BOTH(WIFISUPPORT, ESP3D_WIFISUPPORT)
   #error "Only enable one WiFi option, either WIFISUPPORT or ESP3D_WIFISUPPORT."
 #endif
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+  #error "POSTMORTEM_DEBUGGING is not yet supported on ESP32."
+#endif

Marlin/src/HAL/HAL.h

@@ -29,12 +29,6 @@
 
 #include HAL_PATH(.,HAL.h)
 
-#ifdef SERIAL_PORT_2
-  #define NUM_SERIAL 2
-#else
-  #define NUM_SERIAL 1
-#endif
-
 #define HAL_ADC_RANGE _BV(HAL_ADC_RESOLUTION)
 
 #ifndef I2C_ADDRESS

Marlin/src/HAL/LINUX/HAL.cpp

@@ -73,4 +73,6 @@ void HAL_pwm_init() {
 
 }
 
+void HAL_reboot() { /* Reset the application state and GPIO */ }
+
 #endif // __PLAT_LINUX__

Marlin/src/HAL/LINUX/HAL.h

@@ -61,7 +61,7 @@ uint8_t _getc();
 #define SHARED_SERVOS HAS_SERVOS
 
 extern MSerialT usb_serial;
-#define MYSERIAL0 usb_serial
+#define MYSERIAL1 usb_serial
 
 #define ST7920_DELAY_1 DELAY_NS(600)
 #define ST7920_DELAY_2 DELAY_NS(750)
@@ -107,7 +107,7 @@ uint16_t HAL_adc_get_result();
 inline void HAL_clear_reset_source(void) {}
 inline uint8_t HAL_get_reset_source(void) { return RST_POWER_ON; }
 
-inline void HAL_reboot() {}  // reboot the board or restart the bootloader
+void HAL_reboot(); // Reset the application state and GPIO
 
 /* ---------------- Delay in cycles */
 FORCE_INLINE static void DELAY_CYCLES(uint64_t x) {

Marlin/src/HAL/LINUX/hardware/Gpio.h

@@ -40,7 +40,7 @@ struct GpioEvent {
   pin_type pin_id;
   GpioEvent::Type event;
 
-  GpioEvent(uint64_t timestamp, pin_type pin_id, GpioEvent::Type event){
+  GpioEvent(uint64_t timestamp, pin_type pin_id, GpioEvent::Type event) {
     this->timestamp = timestamp;
     this->pin_id = pin_id;
     this->event = event;

Marlin/src/HAL/LINUX/hardware/Heater.cpp

@@ -54,7 +54,7 @@ void Heater::update() {
 }
 
 void Heater::interrupt(GpioEvent ev) {
-  // ununsed
+  // unused
 }
 
 #endif // __PLAT_LINUX__

Marlin/src/HAL/LINUX/hardware/LinearAxis.cpp

@@ -51,7 +51,7 @@ void LinearAxis::update() {
 }
 
 void LinearAxis::interrupt(GpioEvent ev) {
-  if (ev.pin_id == step_pin && !Gpio::pin_map[enable_pin].value){
+  if (ev.pin_id == step_pin && !Gpio::pin_map[enable_pin].value) {
     if (ev.event == GpioEvent::RISE) {
       last_update = ev.timestamp;
       position += -1 + 2 * Gpio::pin_map[dir_pin].value;

Marlin/src/HAL/LINUX/hardware/Timer.h

@@ -52,7 +52,7 @@ public:
     return (*(intptr_t*)timerid);
   }
 
-  static void handler(int sig, siginfo_t *si, void *uc){
+  static void handler(int sig, siginfo_t *si, void *uc) {
     Timer* _this = (Timer*)si->si_value.sival_ptr;
     _this->avg_error += (Clock::nanos() - _this->start_time) - _this->period; //high_resolution_clock is also limited in precision, but best we have
     _this->avg_error /= 2; //very crude precision analysis (actually within +-500ns usually)

Marlin/src/HAL/LINUX/inc/SanityCheck.h

@@ -35,5 +35,9 @@
 #endif
 
 #if HAS_TMC_SW_SERIAL
-  #error "TMC220x Software Serial is not supported on this platform."
+  #error "TMC220x Software Serial is not supported on LINUX."
+#endif
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+  #error "POSTMORTEM_DEBUGGING is not yet supported on LINUX."
 #endif

Marlin/src/HAL/LINUX/include/pinmapping.cpp

@@ -25,43 +25,6 @@
 
 #include "../../../gcode/parser.h"
 
-uint8_t analog_offset = NUM_DIGITAL_PINS - NUM_ANALOG_INPUTS;
-
-// Get the digital pin for an analog index
-pin_t analogInputToDigitalPin(const int8_t p) {
-  return (WITHIN(p, 0, NUM_ANALOG_INPUTS) ? analog_offset + p : P_NC);
-}
-
-// Return the index of a pin number
-int16_t GET_PIN_MAP_INDEX(const pin_t pin) {
-  return pin;
-}
-
-// Test whether the pin is valid
-bool VALID_PIN(const pin_t p) {
-  return WITHIN(p, 0, NUM_DIGITAL_PINS);
-}
-
-// Get the analog index for a digital pin
-int8_t DIGITAL_PIN_TO_ANALOG_PIN(const pin_t p) {
-  return (WITHIN(p, analog_offset, NUM_DIGITAL_PINS) ? p - analog_offset : P_NC);
-}
-
-// Test whether the pin is PWM
-bool PWM_PIN(const pin_t p) {
-  return false;
-}
-
-// Test whether the pin is interruptable
-bool INTERRUPT_PIN(const pin_t p) {
-  return false;
-}
-
-// Get the pin number at the given index
-pin_t GET_PIN_MAP_PIN(const int16_t ind) {
-  return ind;
-}
-
 int16_t PARSED_PIN_INDEX(const char code, const int16_t dval) {
   return parser.intval(code, dval);
 }

Marlin/src/HAL/LINUX/include/pinmapping.h

@@ -34,26 +34,32 @@ constexpr uint8_t NUM_ANALOG_INPUTS = 16;
 
 #define HAL_SENSITIVE_PINS
 
+constexpr uint8_t analog_offset = NUM_DIGITAL_PINS - NUM_ANALOG_INPUTS;
+
 // Get the digital pin for an analog index
-pin_t analogInputToDigitalPin(const int8_t p);
-
-// Return the index of a pin number
-int16_t GET_PIN_MAP_INDEX(const pin_t pin);
-
-// Test whether the pin is valid
-bool VALID_PIN(const pin_t p);
+constexpr pin_t analogInputToDigitalPin(const int8_t p) {
+  return (WITHIN(p, 0, NUM_ANALOG_INPUTS) ? analog_offset + p : P_NC);
+}
 
 // Get the analog index for a digital pin
-int8_t DIGITAL_PIN_TO_ANALOG_PIN(const pin_t p);
+constexpr int8_t DIGITAL_PIN_TO_ANALOG_PIN(const pin_t p) {
+  return (WITHIN(p, analog_offset, NUM_DIGITAL_PINS) ? p - analog_offset : P_NC);
+}
+
+// Return the index of a pin number
+constexpr int16_t GET_PIN_MAP_INDEX(const pin_t pin) { return pin; }
+
+// Test whether the pin is valid
+constexpr bool VALID_PIN(const pin_t p) { return WITHIN(p, 0, NUM_DIGITAL_PINS); }
 
 // Test whether the pin is PWM
-bool PWM_PIN(const pin_t p);
+constexpr bool PWM_PIN(const pin_t p) { return false; }
 
-// Test whether the pin is interruptable
-bool INTERRUPT_PIN(const pin_t p);
+// Test whether the pin is interruptible
+constexpr bool INTERRUPT_PIN(const pin_t p) { return false; }
 
 // Get the pin number at the given index
-pin_t GET_PIN_MAP_PIN(const int16_t ind);
+constexpr pin_t GET_PIN_MAP_PIN(const int16_t ind) { return ind; }
 
 // Parse a G-code word into a pin index
 int16_t PARSED_PIN_INDEX(const char code, const int16_t dval);

Marlin/src/HAL/LINUX/include/serial.h

@@ -115,4 +115,4 @@ struct HalSerial {
   volatile bool host_connected;
 };
 
-typedef Serial0Type<HalSerial> MSerialT;
+typedef Serial1Class<HalSerial> MSerialT;

Marlin/src/HAL/LINUX/main.cpp

@@ -105,8 +105,8 @@ int main() {
   std::thread write_serial (write_serial_thread);
   std::thread read_serial (read_serial_thread);
 
-  #ifdef MYSERIAL0
-    MYSERIAL0.begin(BAUDRATE);
+  #ifdef MYSERIAL1
+    MYSERIAL1.begin(BAUDRATE);
     SERIAL_ECHOLNPGM("x86_64 Initialized");
     SERIAL_FLUSHTX();
   #endif

Marlin/src/HAL/LPC1768/DebugMonitor.cpp

@@ -1,322 +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 TARGET_LPC1768
-
-#include "../../core/macros.h"
-#include "../../core/serial.h"
-#include <stdarg.h>
-
-#include "../shared/backtrace/unwinder.h"
-#include "../shared/backtrace/unwmemaccess.h"
-#include "watchdog.h"
-#include <debug_frmwrk.h>
-
-
-// Debug monitor that dumps to the Programming port all status when
-// an exception or WDT timeout happens - And then resets the board
-
-// All the Monitor routines must run with interrupts disabled and
-// under an ISR execution context. That is why we cannot reuse the
-// Serial interrupt routines or any C runtime, as we don't know the
-// state we are when running them
-
-// A SW memory barrier, to ensure GCC does not overoptimize loops
-#define sw_barrier() __asm__ volatile("": : :"memory");
-
-// (re)initialize UART0 as a monitor output to 250000,n,8,1
-static void TXBegin() {
-}
-
-// Send character through UART with no interrupts
-static void TX(char c) {
-  _DBC(c);
-}
-
-// Send String through UART
-static void TX(const char* s) {
-  while (*s) TX(*s++);
-}
-
-static void TXDigit(uint32_t d) {
-  if (d < 10) TX((char)(d+'0'));
-  else if (d < 16) TX((char)(d+'A'-10));
-  else TX('?');
-}
-
-// Send Hex number thru UART
-static void TXHex(uint32_t v) {
-  TX("0x");
-  for (uint8_t i = 0; i < 8; i++, v <<= 4)
-    TXDigit((v >> 28) & 0xF);
-}
-
-// Send Decimal number thru UART
-static void TXDec(uint32_t v) {
-  if (!v) {
-    TX('0');
-    return;
-  }
-
-  char nbrs[14];
-  char *p = &nbrs[0];
-  while (v != 0) {
-    *p++ = '0' + (v % 10);
-    v /= 10;
-  }
-  do {
-    p--;
-    TX(*p);
-  } while (p != &nbrs[0]);
-}
-
-// Dump a backtrace entry
-static bool UnwReportOut(void* ctx, const UnwReport* bte) {
-  int* p = (int*)ctx;
-
-  (*p)++;
-  TX('#'); TXDec(*p); TX(" : ");
-  TX(bte->name?bte->name:"unknown"); TX('@'); TXHex(bte->function);
-  TX('+'); TXDec(bte->address - bte->function);
-  TX(" PC:");TXHex(bte->address); TX('\n');
-  return true;
-}
-
-#ifdef UNW_DEBUG
-  void UnwPrintf(const char* format, ...) {
-    char dest[256];
-    va_list argptr;
-    va_start(argptr, format);
-    vsprintf(dest, format, argptr);
-    va_end(argptr);
-    TX(&dest[0]);
-  }
-#endif
-
-/* Table of function pointers for passing to the unwinder */
-static const UnwindCallbacks UnwCallbacks = {
-  UnwReportOut,
-  UnwReadW,
-  UnwReadH,
-  UnwReadB
-  #ifdef UNW_DEBUG
-   ,UnwPrintf
-  #endif
-};
-
-
-/**
- * HardFaultHandler_C:
- * This is called from the HardFault_HandlerAsm with a pointer the Fault stack
- * as the parameter. We can then read the values from the stack and place them
- * into local variables for ease of reading.
- * We then read the various Fault Status and Address Registers to help decode
- * cause of the fault.
- * The function ends with a BKPT instruction to force control back into the debugger
- */
-extern "C"
-void HardFault_HandlerC(unsigned long *sp, unsigned long lr, unsigned long cause) {
-
-  static const char* causestr[] = {
-    "NMI","Hard","Mem","Bus","Usage","Debug","WDT","RSTC"
-  };
-
-  UnwindFrame btf;
-
-  // Dump report to the Programming port (interrupts are DISABLED)
-  TXBegin();
-  TX("\n\n## Software Fault detected ##\n");
-  TX("Cause: "); TX(causestr[cause]); TX('\n');
-
-  TX("R0   : "); TXHex(((unsigned long)sp[0])); TX('\n');
-  TX("R1   : "); TXHex(((unsigned long)sp[1])); TX('\n');
-  TX("R2   : "); TXHex(((unsigned long)sp[2])); TX('\n');
-  TX("R3   : "); TXHex(((unsigned long)sp[3])); TX('\n');
-  TX("R12  : "); TXHex(((unsigned long)sp[4])); TX('\n');
-  TX("LR   : "); TXHex(((unsigned long)sp[5])); TX('\n');
-  TX("PC   : "); TXHex(((unsigned long)sp[6])); TX('\n');
-  TX("PSR  : "); TXHex(((unsigned long)sp[7])); TX('\n');
-
-  // Configurable Fault Status Register
-  // Consists of MMSR, BFSR and UFSR
-  TX("CFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED28)))); TX('\n');
-
-  // Hard Fault Status Register
-  TX("HFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED2C)))); TX('\n');
-
-  // Debug Fault Status Register
-  TX("DFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED30)))); TX('\n');
-
-  // Auxiliary Fault Status Register
-  TX("AFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED3C)))); TX('\n');
-
-  // Read the Fault Address Registers. These may not contain valid values.
-  // Check BFARVALID/MMARVALID to see if they are valid values
-  // MemManage Fault Address Register
-  TX("MMAR : "); TXHex((*((volatile unsigned long *)(0xE000ED34)))); TX('\n');
-
-  // Bus Fault Address Register
-  TX("BFAR : "); TXHex((*((volatile unsigned long *)(0xE000ED38)))); TX('\n');
-
-  TX("ExcLR: "); TXHex(lr); TX('\n');
-  TX("ExcSP: "); TXHex((unsigned long)sp); TX('\n');
-
-  btf.sp = ((unsigned long)sp) + 8*4; // The original stack pointer
-  btf.fp = btf.sp;
-  btf.lr = ((unsigned long)sp[5]);
-  btf.pc = ((unsigned long)sp[6]) | 1; // Force Thumb, as CORTEX only support it
-
-  // Perform a backtrace
-  TX("\nBacktrace:\n\n");
-  int ctr = 0;
-  UnwindStart(&btf, &UnwCallbacks, &ctr);
-
-  // Disable all NVIC interrupts
-  NVIC->ICER[0] = 0xFFFFFFFF;
-  NVIC->ICER[1] = 0xFFFFFFFF;
-
-  // Relocate VTOR table to default position
-  SCB->VTOR = 0;
-
-  // Clear cause of reset to prevent entering smoothie bootstrap
-  HAL_clear_reset_source();
-
-  // Restart watchdog
-  #if ENABLED(USE_WATCHDOG)
-    //WDT_Restart(WDT);
-    watchdog_init();
-  #endif
-
-  // Reset controller
-  NVIC_SystemReset();
-
-  // Nothing below here is compiled because NVIC_SystemReset loops forever
-
-  for (;;) { TERN_(USE_WATCHDOG, watchdog_init()); }
-}
-
-extern "C" {
-__attribute__((naked)) void NMI_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#0")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void HardFault_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#1")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void MemManage_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#2")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void BusFault_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#3")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void UsageFault_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#4")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void DebugMon_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#5")
-    A("b HardFault_HandlerC")
-  );
-}
-
-/* This is NOT an exception, it is an interrupt handler - Nevertheless, the framing is the same */
-__attribute__((naked)) void WDT_IRQHandler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#6")
-    A("b HardFault_HandlerC")
-  );
-}
-
-__attribute__((naked)) void RSTC_Handler() {
-  __asm__ __volatile__ (
-    ".syntax unified" "\n\t"
-    A("tst lr, #4")
-    A("ite eq")
-    A("mrseq r0, msp")
-    A("mrsne r0, psp")
-    A("mov r1,lr")
-    A("mov r2,#7")
-    A("b HardFault_HandlerC")
-  );
-}
-}
-#endif // TARGET_LPC1768

Marlin/src/HAL/LPC1768/HAL.cpp

@@ -29,7 +29,7 @@
   #include "watchdog.h"
 #endif
 
-DefaultSerial USBSerial(false, UsbSerial);
+DefaultSerial1 USBSerial(false, UsbSerial);
 
 uint32_t HAL_adc_reading = 0;
 
@@ -67,7 +67,7 @@ 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
-  NVIC_SystemReset();
+  HAL_reboot();
 }
 
 void HAL_clear_reset_source(void) {
@@ -81,4 +81,6 @@ uint8_t HAL_get_reset_source(void) {
   return RST_POWER_ON;
 }
 
+void HAL_reboot() { NVIC_SystemReset(); }
+
 #endif // TARGET_LPC1768

Marlin/src/HAL/LPC1768/HAL.h

@@ -60,28 +60,37 @@ extern "C" volatile uint32_t _millis;
   #define ST7920_DELAY_3 DELAY_NS(750)
 #endif
 
-typedef ForwardSerial0Type< decltype(UsbSerial) > DefaultSerial;
-extern DefaultSerial USBSerial;
+typedef ForwardSerial1Class< decltype(UsbSerial) > DefaultSerial1;
+extern DefaultSerial1 USBSerial;
 
 #define _MSERIAL(X) MSerial##X
 #define MSERIAL(X) _MSERIAL(X)
-#define MSerial0 MSerial
 
 #if SERIAL_PORT == -1
-  #define MYSERIAL0 USBSerial
+  #define MYSERIAL1 USBSerial
 #elif WITHIN(SERIAL_PORT, 0, 3)
-  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
+  #define MYSERIAL1 MSERIAL(SERIAL_PORT)
 #else
-  #error "SERIAL_PORT must be from -1 to 3. Please update your configuration."
+  #error "SERIAL_PORT must be from 0 to 3. You can also use -1 if the board supports Native USB."
 #endif
 
 #ifdef SERIAL_PORT_2
   #if SERIAL_PORT_2 == -1
-    #define MYSERIAL1 USBSerial
+    #define MYSERIAL2 USBSerial
   #elif WITHIN(SERIAL_PORT_2, 0, 3)
-    #define MYSERIAL1 MSERIAL(SERIAL_PORT_2)
+    #define MYSERIAL2 MSERIAL(SERIAL_PORT_2)
   #else
-    #error "SERIAL_PORT_2 must be from -1 to 3. Please update your configuration."
+    #error "SERIAL_PORT_2 must be from 0 to 3. You can also use -1 if the board supports Native USB."
+  #endif
+#endif
+
+#ifdef SERIAL_PORT_3
+  #if SERIAL_PORT_3 == -1
+    #define MYSERIAL3 USBSerial
+  #elif WITHIN(SERIAL_PORT_3, 0, 3)
+    #define MYSERIAL3 MSERIAL(SERIAL_PORT_3)
+  #else
+    #error "SERIAL_PORT_3 must be from 0 to 3. You can also use -1 if the board supports Native USB."
   #endif
 #endif
 
@@ -91,7 +100,7 @@ extern DefaultSerial USBSerial;
   #elif WITHIN(MMU2_SERIAL_PORT, 0, 3)
     #define MMU2_SERIAL MSERIAL(MMU2_SERIAL_PORT)
   #else
-    #error "MMU2_SERIAL_PORT must be from -1 to 3. Please update your configuration."
+    #error "MMU2_SERIAL_PORT must be from 0 to 3. You can also use -1 if the board supports Native USB."
   #endif
 #endif
 
@@ -101,7 +110,10 @@ extern DefaultSerial USBSerial;
   #elif WITHIN(LCD_SERIAL_PORT, 0, 3)
     #define LCD_SERIAL MSERIAL(LCD_SERIAL_PORT)
   #else
-    #error "LCD_SERIAL_PORT must be from -1 to 3. Please update your configuration."
+    #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()
   #endif
 #endif
 
@@ -186,7 +198,7 @@ constexpr pin_t GET_PIN_MAP_PIN(const int16_t index) {
 // Parse a G-code word into a pin index
 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_SENSITIVE_PINS P0_06, P0_07, P0_08, P0_09,
 
 #define HAL_IDLETASK 1
 void HAL_idletask();
@@ -216,4 +228,4 @@ void set_pwm_duty(const pin_t pin, const uint16_t v, const uint16_t v_size=255,
 void HAL_clear_reset_source(void);
 uint8_t HAL_get_reset_source(void);
 
-inline void HAL_reboot() {}  // reboot the board or restart the bootloader
+void HAL_reboot();

Marlin/src/HAL/LPC1768/HAL_MinSerial.cpp

@@ -0,0 +1,51 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2021 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 TARGET_LPC1768
+
+#include "../../inc/MarlinConfig.h"
+#include "HAL.h"
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+
+#include "../shared/HAL_MinSerial.h"
+#include <debug_frmwrk.h>
+
+static void TX(char c) { _DBC(c); }
+void install_min_serial() { HAL_min_serial_out = &TX; }
+
+#if DISABLED(DYNAMIC_VECTORTABLE)
+extern "C" {
+  __attribute__((naked)) void JumpHandler_ASM() {
+    __asm__ __volatile__ (
+      "b CommonHandler_ASM\n"
+    );
+  }
+  void __attribute__((naked, alias("JumpHandler_ASM"))) HardFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) BusFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) UsageFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) MemManage_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"))) NMI_Handler();
+}
+#endif
+
+#endif // POSTMORTEM_DEBUGGING
+#endif // TARGET_LPC1768

Marlin/src/HAL/LPC1768/HAL_SPI.cpp

@@ -66,11 +66,7 @@
 
   #include <SoftwareSPI.h>
 
-  #ifndef HAL_SPI_SPEED
-    #define HAL_SPI_SPEED SPI_FULL_SPEED
-  #endif
-
-  static uint8_t SPI_speed = HAL_SPI_SPEED;
+  static uint8_t SPI_speed = SPI_FULL_SPEED;
 
   static uint8_t spiTransfer(uint8_t b) {
     return swSpiTransfer(b, SPI_speed, SD_SCK_PIN, SD_MISO_PIN, SD_MOSI_PIN);
@@ -93,12 +89,12 @@
 
   void spiSend(uint8_t b) { (void)spiTransfer(b); }
 
-  void spiSend(const uint8_t* buf, size_t nbyte) {
+  void spiSend(const uint8_t *buf, size_t nbyte) {
     for (uint16_t i = 0; i < nbyte; i++)
       (void)spiTransfer(buf[i]);
   }
 
-  void spiSendBlock(uint8_t token, const uint8_t* buf) {
+  void spiSendBlock(uint8_t token, const uint8_t *buf) {
     (void)spiTransfer(token);
     for (uint16_t i = 0; i < 512; i++)
       (void)spiTransfer(buf[i]);
@@ -106,15 +102,13 @@
 
 #else
 
-  #ifndef HAL_SPI_SPEED
-    #ifdef SD_SPI_SPEED
-      #define HAL_SPI_SPEED SD_SPI_SPEED
-    #else
-      #define HAL_SPI_SPEED SPI_FULL_SPEED
-    #endif
+  #ifdef SD_SPI_SPEED
+    #define INIT_SPI_SPEED SD_SPI_SPEED
+  #else
+    #define INIT_SPI_SPEED SPI_FULL_SPEED
   #endif
 
-  void spiBegin() { spiInit(HAL_SPI_SPEED); } // Set up SCK, MOSI & MISO pins for SSP0
+  void spiBegin() { spiInit(INIT_SPI_SPEED); } // Set up SCK, MOSI & MISO pins for SSP0
 
   void spiInit(uint8_t spiRate) {
     #if SD_MISO_PIN == BOARD_SPI1_MISO_PIN
@@ -135,13 +129,13 @@
 
   void spiSend(uint8_t b) { doio(b); }
 
-  void spiSend(const uint8_t* buf, size_t nbyte) {
+  void spiSend(const uint8_t *buf, size_t nbyte) {
     for (uint16_t i = 0; i < nbyte; i++) doio(buf[i]);
   }
 
   void spiSend(uint32_t chan, byte b) {}
 
-  void spiSend(uint32_t chan, const uint8_t* buf, size_t nbyte) {}
+  void spiSend(uint32_t chan, const uint8_t *buf, size_t nbyte) {}
 
   // Read single byte from SPI
   uint8_t spiRec() { return doio(0xFF); }
@@ -156,7 +150,7 @@
   uint8_t spiTransfer(uint8_t b) { return doio(b); }
 
   // Write from buffer to SPI
-  void spiSendBlock(uint8_t token, const uint8_t* buf) {
+  void spiSendBlock(uint8_t token, const uint8_t *buf) {
    (void)spiTransfer(token);
     for (uint16_t i = 0; i < 512; i++)
       (void)spiTransfer(buf[i]);

Marlin/src/HAL/LPC1768/MarlinSerial.cpp

@@ -21,24 +21,51 @@
  */
 #ifdef TARGET_LPC1768
 
-#include "../../inc/MarlinConfigPre.h"
 #include "MarlinSerial.h"
 
-#if ANY_SERIAL_IS(0)
-  MSerialT MSerial(true, LPC_UART0);
-  extern "C" void UART0_IRQHandler() { MSerial.IRQHandler(); }
+#include "../../inc/MarlinConfig.h"
+
+#if USING_HW_SERIAL0
+  MarlinSerial _MSerial0(LPC_UART0);
+  MSerialT MSerial0(true, _MSerial0);
+  extern "C" void UART0_IRQHandler() { _MSerial0.IRQHandler(); }
 #endif
-#if ANY_SERIAL_IS(1)
-  MSerialT MSerial1(true, (LPC_UART_TypeDef *) LPC_UART1);
-  extern "C" void UART1_IRQHandler() { MSerial1.IRQHandler(); }
+#if USING_HW_SERIAL1
+  MarlinSerial _MSerial1((LPC_UART_TypeDef *) LPC_UART1);
+  MSerialT MSerial1(true, _MSerial1);
+  extern "C" void UART1_IRQHandler() { _MSerial1.IRQHandler(); }
 #endif
-#if ANY_SERIAL_IS(2)
-  MSerialT MSerial2(true, LPC_UART2);
-  extern "C" void UART2_IRQHandler() { MSerial2.IRQHandler(); }
+#if USING_HW_SERIAL2
+  MarlinSerial _MSerial2(LPC_UART2);
+  MSerialT MSerial2(true, _MSerial2);
+  extern "C" void UART2_IRQHandler() { _MSerial2.IRQHandler(); }
 #endif
-#if ANY_SERIAL_IS(3)
-  MSerialT MSerial3(true, LPC_UART3);
-  extern "C" void UART3_IRQHandler() { MSerial3.IRQHandler(); }
+#if USING_HW_SERIAL3
+  MarlinSerial _MSerial3(LPC_UART3);
+  MSerialT MSerial3(true, _MSerial3);
+  extern "C" void UART3_IRQHandler() { _MSerial3.IRQHandler(); }
+#endif
+
+#if ENABLED(EMERGENCY_PARSER)
+
+  bool MarlinSerial::recv_callback(const char c) {
+    // Need to figure out which serial port we are and react in consequence (Marlin does not have CONTAINER_OF macro)
+    if (false) {}
+    #if USING_HW_SERIAL0
+      else if (this == &_MSerial0) emergency_parser.update(MSerial0.emergency_state, c);
+    #endif
+    #if USING_HW_SERIAL1
+      else if (this == &_MSerial1) emergency_parser.update(MSerial1.emergency_state, c);
+    #endif
+    #if USING_HW_SERIAL2
+      else if (this == &_MSerial2) emergency_parser.update(MSerial2.emergency_state, c);
+    #endif
+    #if USING_HW_SERIAL3
+      else if (this == &_MSerial3) emergency_parser.update(MSerial3.emergency_state, c);
+    #endif
+    return true;
+  }
+
 #endif
 
 #endif // TARGET_LPC1768

Marlin/src/HAL/LPC1768/MarlinSerial.h

@@ -47,15 +47,21 @@ public:
   void end() {}
 
   #if ENABLED(EMERGENCY_PARSER)
-    bool recv_callback(const char c) override {
-      emergency_parser.update(static_cast<Serial0Type<MarlinSerial> *>(this)->emergency_state, c);
-      return true; // do not discard character
-    }
+    bool recv_callback(const char c) override;
   #endif
 };
 
-typedef Serial0Type<MarlinSerial> MSerialT;
-extern MSerialT MSerial;
+// On LPC176x framework, HardwareSerial does not implement the same interface as Arduino's Serial, so overloads
+// of 'available' and 'read' method are not used in this multiple inheritance scenario.
+// Instead, use a ForwardSerial here that adapts the interface.
+typedef ForwardSerial1Class<MarlinSerial> MSerialT;
+extern MSerialT MSerial0;
 extern MSerialT MSerial1;
 extern MSerialT MSerial2;
 extern MSerialT MSerial3;
+
+// Consequently, we can't use a RuntimeSerial either. The workaround would be to use
+// a RuntimeSerial<ForwardSerial<MarlinSerial>> type here. Ignore for now until it's actually required.
+#if ENABLED(SERIAL_RUNTIME_HOOK)
+  #error "SERIAL_RUNTIME_HOOK is not yet supported for LPC176x."
+#endif

Marlin/src/HAL/LPC1768/eeprom_sdcard.cpp

@@ -83,14 +83,13 @@ bool PersistentStore::access_finish() {
 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(' ');
-  serialprintPGM(rw_str);
+  SERIAL_ECHOPGM_P(rw_str);
   SERIAL_ECHOLNPAIR("_data(", pos, ",", value, ",", size, ", ...)");
   if (total) {
     SERIAL_ECHOPGM(" f_");
-    serialprintPGM(rw_str);
+    SERIAL_ECHOPGM_P(rw_str);
     SERIAL_ECHOPAIR("()=", s, "\n size=", size, "\n bytes_");
-    serialprintPGM(write ? PSTR("written=") : PSTR("read="));
-    SERIAL_ECHOLN(total);
+    SERIAL_ECHOLNPAIR_P(write ? PSTR("written=") : PSTR("read="), total);
   }
   else
     SERIAL_ECHOLNPAIR(" f_lseek()=", s);

Marlin/src/HAL/LPC1768/eeprom_wired.cpp

@@ -42,25 +42,22 @@ bool PersistentStore::access_start()  { eeprom_init(); return true; }
 bool PersistentStore::access_finish() { return true; }
 
 bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  uint16_t written = 0;
   while (size--) {
     uint8_t v = *value;
-
-    // EEPROM has only ~100,000 write cycles,
-    // so only write bytes that have changed!
     uint8_t * const p = (uint8_t * const)pos;
-    if (v != eeprom_read_byte(p)) {
+    if (v != eeprom_read_byte(p)) { // EEPROM has only ~100,000 write cycles, so only write bytes that have changed!
       eeprom_write_byte(p, v);
+      if (++written & 0x7F) delay(2); else safe_delay(2); // Avoid triggering watchdog during long EEPROM writes
       if (eeprom_read_byte(p) != v) {
         SERIAL_ECHO_MSG(STR_ERR_EEPROM_WRITE);
         return true;
       }
     }
-
     crc16(crc, &v, 1);
     pos++;
     value++;
-  };
-
+  }
   return false;
 }
 
@@ -68,7 +65,6 @@ bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t
   do {
     // Read from external EEPROM
     const uint8_t c = eeprom_read_byte((uint8_t*)pos);
-
     if (writing) *value = c;
     crc16(crc, &c, 1);
     pos++;

Marlin/src/HAL/LPC1768/endstop_interrupts.h

@@ -122,4 +122,37 @@ void setup_endstop_interrupts() {
     #endif
     _ATTACH(Z_MIN_PROBE_PIN);
   #endif
+  #if HAS_I_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(I_MAX_PIN)
+      #error "I_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(I_MAX_PIN);
+  #elif HAS_I_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(I_MIN_PIN)
+      #error "I_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(I_MIN_PIN);
+  #endif
+  #if HAS_J_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(J_MAX_PIN)
+      #error "J_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(J_MAX_PIN);
+  #elif HAS_J_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(J_MIN_PIN)
+      #error "J_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(J_MIN_PIN);
+  #endif
+  #if HAS_K_MAX
+    #if !LPC1768_PIN_INTERRUPT_M(K_MAX_PIN)
+      #error "K_MAX_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(K_MAX_PIN);
+  #elif HAS_K_MIN
+    #if !LPC1768_PIN_INTERRUPT_M(K_MIN_PIN)
+      #error "K_MIN_PIN is not INTERRUPT-capable."
+    #endif
+    _ATTACH(K_MIN_PIN);
+  #endif
 }

Marlin/src/HAL/LPC1768/inc/Conditionals_post.h

@@ -30,6 +30,5 @@
 // LPC1768 boards seem to lose steps when saving to EEPROM during print (issue #20785)
 // TODO: Which other boards are incompatible?
 #if defined(MCU_LPC1768) && PRINTCOUNTER_SAVE_INTERVAL > 0
-  #warning "To prevent step loss, motion will pause for PRINTCOUNTER auto-save."
   #define PRINTCOUNTER_SYNC 1
 #endif

Marlin/src/HAL/LPC1768/inc/SanityCheck.h

@@ -92,7 +92,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
 #define ANY_TX(N,V...) DO(IS_TX##N,||,V)
 #define ANY_RX(N,V...) DO(IS_RX##N,||,V)
 
-#if ANY_SERIAL_IS(0)
+#if USING_HW_SERIAL0
   #define IS_TX0(P) (P == P0_02)
   #define IS_RX0(P) (P == P0_03)
   #if IS_TX0(TMC_SW_MISO) || IS_RX0(TMC_SW_MOSI)
@@ -106,7 +106,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
   #undef IS_RX0
 #endif
 
-#if ANY_SERIAL_IS(1)
+#if USING_HW_SERIAL1
   #define IS_TX1(P) (P == P0_15)
   #define IS_RX1(P) (P == P0_16)
   #define _IS_TX1_1 IS_TX1
@@ -127,7 +127,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
   #undef _IS_RX1_1
 #endif
 
-#if ANY_SERIAL_IS(2)
+#if USING_HW_SERIAL2
   #define IS_TX2(P) (P == P0_10)
   #define IS_RX2(P) (P == P0_11)
   #define _IS_TX2_1 IS_TX2
@@ -144,9 +144,9 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
     #error "Serial port pins (2) conflict with Z4 pins!"
   #elif ANY_RX(2, X_DIR_PIN, Y_DIR_PIN)
     #error "Serial port pins (2) conflict with other pins!"
-  #elif Y_HOME_DIR < 0 && IS_TX2(Y_STOP_PIN)
+  #elif Y_HOME_TO_MIN && IS_TX2(Y_STOP_PIN)
     #error "Serial port pins (2) conflict with Y endstop pin!"
-  #elif HAS_CUSTOM_PROBE_PIN && IS_TX2(Z_MIN_PROBE_PIN)
+  #elif USES_Z_MIN_PROBE_PIN && IS_TX2(Z_MIN_PROBE_PIN)
     #error "Serial port pins (2) conflict with probe pin!"
   #elif ANY_TX(2, X_ENABLE_PIN, Y_ENABLE_PIN) || ANY_RX(2, X_DIR_PIN, Y_DIR_PIN)
     #error "Serial port pins (2) conflict with X/Y stepper pins!"
@@ -161,7 +161,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
   #undef _IS_RX2_1
 #endif
 
-#if ANY_SERIAL_IS(3)
+#if USING_HW_SERIAL3
   #define PIN_IS_TX3(P) (PIN_EXISTS(P) && P##_PIN == P0_00)
   #define PIN_IS_RX3(P) (P##_PIN == P0_01)
   #if PIN_IS_TX3(X_MIN) || PIN_IS_RX3(X_MAX)
@@ -237,7 +237,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
     #define PIN_IS_SCL2(P) (P##_PIN == P0_11)
     #if PIN_IS_SDA2(Y_STOP)
       #error "i2c SDA2 overlaps with Y endstop pin!"
-    #elif HAS_CUSTOM_PROBE_PIN && PIN_IS_SDA2(Z_MIN_PROBE)
+    #elif USES_Z_MIN_PROBE_PIN && PIN_IS_SDA2(Z_MIN_PROBE)
       #error "i2c SDA2 overlaps with Z probe pin!"
     #elif PIN_IS_SDA2(X_ENABLE) || PIN_IS_SDA2(Y_ENABLE)
       #error "i2c SDA2 overlaps with X/Y ENABLE pin!"
@@ -270,7 +270,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
 #endif
 
 #if ENABLED(SERIAL_STATS_MAX_RX_QUEUED)
-  #error "SERIAL_STATS_MAX_RX_QUEUED is not supported on this platform."
+  #error "SERIAL_STATS_MAX_RX_QUEUED is not supported on LPC176x."
 #elif ENABLED(SERIAL_STATS_DROPPED_RX)
-  #error "SERIAL_STATS_DROPPED_RX is not supported on this platform."
+  #error "SERIAL_STATS_DROPPED_RX is not supported on LPX176x."
 #endif

Marlin/src/HAL/LPC1768/main.cpp

@@ -46,6 +46,8 @@ extern "C" {
 
 void SysTick_Callback() { disk_timerproc(); }
 
+TERN_(POSTMORTEM_DEBUGGING, extern void install_min_serial());
+
 void HAL_init() {
 
   // Init LEDs
@@ -115,7 +117,7 @@ void HAL_init() {
     PinCfg.Pinmode = 2;    // no pull-up/pull-down
     PINSEL_ConfigPin(&PinCfg);
     // now set CLKOUT_EN bit
-    LPC_SC->CLKOUTCFG |= (1<<8);
+    SBI(LPC_SC->CLKOUTCFG, 8);
   #endif
 
   USB_Init();                               // USB Initialization
@@ -123,9 +125,7 @@ void HAL_init() {
   delay(1000);                              // Give OS time to notice
   USB_Connect(true);
 
-  #if HAS_SD_HOST_DRIVE
-    MSC_SD_Init(0);                         // Enable USB SD card access
-  #endif
+  TERN_(HAS_SD_HOST_DRIVE, MSC_SD_Init(0)); // Enable USB SD card access
 
   const millis_t usb_timeout = millis() + 2000;
   while (!USB_Configuration && PENDING(millis(), usb_timeout)) {
@@ -137,6 +137,8 @@ void HAL_init() {
   }
 
   HAL_timer_init();
+
+  TERN_(POSTMORTEM_DEBUGGING, install_min_serial()); // Install the min serial handler
 }
 
 // HAL idle task

Marlin/src/HAL/LPC1768/tft/xpt2046.cpp

@@ -22,7 +22,7 @@
 
 #include "../../../inc/MarlinConfig.h"
 
-#if HAS_TFT_XPT2046 || HAS_TOUCH_BUTTONS
+#if HAS_TFT_XPT2046 || HAS_RES_TOUCH_BUTTONS
 
 #include "xpt2046.h"
 #include <SPI.h>

Marlin/src/HAL/LPC1768/tft/xpt2046.h

@@ -54,7 +54,7 @@ enum XPTCoordinate : uint8_t {
   XPT2046_Z2 = 0x40 | XPT2046_CONTROL | XPT2046_DFR_MODE,
 };
 
-#if !defined(XPT2046_Z1_THRESHOLD)
+#ifndef XPT2046_Z1_THRESHOLD
   #define XPT2046_Z1_THRESHOLD 10
 #endif
 

Marlin/src/HAL/LPC1768/u8g/u8g_com_HAL_LPC1768_hw_spi.cpp

@@ -59,7 +59,7 @@
 
 #if HAS_MARLINUI_U8GLIB
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 #include "../../shared/HAL_SPI.h"
 
 #ifndef LCD_SPI_SPEED

Marlin/src/HAL/LPC1768/u8g/u8g_com_HAL_LPC1768_ssd_hw_i2c.cpp

@@ -79,7 +79,7 @@
 
 #if HAS_MARLINUI_U8GLIB
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 #define I2C_SLA         (0x3C*2)
 //#define I2C_CMD_MODE  0x080

Marlin/src/HAL/LPC1768/u8g/u8g_com_HAL_LPC1768_st7920_hw_spi.cpp

@@ -59,14 +59,14 @@
 
 #if HAS_MARLINUI_U8GLIB
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 #include "../../shared/HAL_SPI.h"
 #include "../../shared/Delay.h"
 
 void spiBegin();
 void spiInit(uint8_t spiRate);
 void spiSend(uint8_t b);
-void spiSend(const uint8_t* buf, size_t n);
+void spiSend(const uint8_t *buf, size_t n);
 
 static uint8_t rs_last_state = 255;
 

Marlin/src/HAL/LPC1768/u8g/u8g_com_HAL_LPC1768_st7920_sw_spi.cpp

@@ -59,7 +59,7 @@
 
 #if ENABLED(U8GLIB_ST7920)
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 #include <SoftwareSPI.h>
 #include "../../shared/Delay.h"
 #include "../../shared/HAL_SPI.h"

Marlin/src/HAL/LPC1768/u8g/u8g_com_HAL_LPC1768_sw_spi.cpp

@@ -71,7 +71,7 @@
 #include <LPC17xx.h>
 #include <gpio.h>
 
-#include <U8glib.h>
+#include <U8glib-HAL.h>
 
 uint8_t swSpiTransfer_mode_0(uint8_t b, const uint8_t spi_speed, const pin_t sck_pin, const pin_t miso_pin, const pin_t mosi_pin ) {
 

Marlin/src/HAL/LPC1768/upload_extra_script.py

@@ -8,9 +8,7 @@ from __future__ import print_function
 target_filename = "FIRMWARE.CUR"
 target_drive = "REARM"
 
-import os
-import getpass
-import platform
+import os,getpass,platform
 
 current_OS = platform.system()
 Import("env")
@@ -22,102 +20,104 @@ def print_error(e):
 		  'or copy the firmware (.pio/build/%s/firmware.bin) manually to the appropriate disk\n' \
 		  %(e, env.get('PIOENV')))
 
-try:
-	#
-	# Find a disk for upload
-	#
-	upload_disk = 'Disk not found'
-	target_file_found = False
-	target_drive_found = False
-	if current_OS == 'Windows':
+def before_upload(source, target, env):
+	try:
 		#
-		# platformio.ini will accept this for a Windows upload port designation: 'upload_port = L:'
-		#   Windows - doesn't care about the disk's name, only cares about the drive letter
-		import subprocess
-		from ctypes import windll
-		import string
+		# Find a disk for upload
+		#
+		upload_disk = 'Disk not found'
+		target_file_found = False
+		target_drive_found = False
+		if current_OS == 'Windows':
+			#
+			# platformio.ini will accept this for a Windows upload port designation: 'upload_port = L:'
+			#   Windows - doesn't care about the disk's name, only cares about the drive letter
+			import subprocess,string
+			from ctypes import windll
 
-		# getting list of drives
-		# https://stackoverflow.com/questions/827371/is-there-a-way-to-list-all-the-available-drive-letters-in-python
-		drives = []
-		bitmask = windll.kernel32.GetLogicalDrives()
-		for letter in string.ascii_uppercase:
-			if bitmask & 1:
-				drives.append(letter)
-			bitmask >>= 1
+			# getting list of drives
+			# https://stackoverflow.com/questions/827371/is-there-a-way-to-list-all-the-available-drive-letters-in-python
+			drives = []
+			bitmask = windll.kernel32.GetLogicalDrives()
+			for letter in string.ascii_uppercase:
+				if bitmask & 1:
+					drives.append(letter)
+				bitmask >>= 1
 
-		for drive in drives:
-			final_drive_name = drive + ':\\'
-			# print ('disc check: {}'.format(final_drive_name))
-			try:
-				volume_info = str(subprocess.check_output('cmd /C dir ' + final_drive_name, stderr=subprocess.STDOUT))
-			except Exception as e:
-				print ('error:{}'.format(e))
-				continue
-			else:
-				if target_drive in volume_info and not target_file_found:  # set upload if not found target file yet
-					target_drive_found = True
-					upload_disk = final_drive_name
-				if target_filename in volume_info:
-					if not target_file_found:
+			for drive in drives:
+				final_drive_name = drive + ':\\'
+				# print ('disc check: {}'.format(final_drive_name))
+				try:
+					volume_info = str(subprocess.check_output('cmd /C dir ' + final_drive_name, stderr=subprocess.STDOUT))
+				except Exception as e:
+					print ('error:{}'.format(e))
+					continue
+				else:
+					if target_drive in volume_info and not target_file_found:  # set upload if not found target file yet
+						target_drive_found = True
 						upload_disk = final_drive_name
-					target_file_found = True
+					if target_filename in volume_info:
+						if not target_file_found:
+							upload_disk = final_drive_name
+						target_file_found = True
 
-	elif current_OS == 'Linux':
-		#
-		# platformio.ini will accept this for a Linux upload port designation: 'upload_port = /media/media_name/drive'
-		#
-		drives = os.listdir(os.path.join(os.sep, 'media', getpass.getuser()))
-		if target_drive in drives:  # If target drive is found, use it.
-			target_drive_found = True
-			upload_disk = os.path.join(os.sep, 'media', getpass.getuser(), target_drive) + os.sep
-		else:
+		elif current_OS == 'Linux':
+			#
+			# platformio.ini will accept this for a Linux upload port designation: 'upload_port = /media/media_name/drive'
+			#
+			drives = os.listdir(os.path.join(os.sep, 'media', getpass.getuser()))
+			if target_drive in drives:  # If target drive is found, use it.
+				target_drive_found = True
+				upload_disk = os.path.join(os.sep, 'media', getpass.getuser(), target_drive) + os.sep
+			else:
+				for drive in drives:
+					try:
+						files = os.listdir(os.path.join(os.sep, 'media', getpass.getuser(), drive))
+					except:
+						continue
+					else:
+						if target_filename in files:
+							upload_disk = os.path.join(os.sep, 'media', getpass.getuser(), drive) + os.sep
+							target_file_found = True
+							break
+			#
+			# set upload_port to drive if found
+			#
+
+			if target_file_found or target_drive_found:
+				env.Replace(
+					UPLOAD_FLAGS="-P$UPLOAD_PORT"
+				)
+
+		elif current_OS == 'Darwin':  # MAC
+			#
+			# platformio.ini will accept this for a OSX upload port designation: 'upload_port = /media/media_name/drive'
+			#
+			drives = os.listdir('/Volumes')  # human readable names
+			if target_drive in drives and not target_file_found:  # set upload if not found target file yet
+				target_drive_found = True
+				upload_disk = '/Volumes/' + target_drive + '/'
 			for drive in drives:
 				try:
-					files = os.listdir(os.path.join(os.sep, 'media', getpass.getuser(), drive))
+					filenames = os.listdir('/Volumes/' + drive + '/')   # will get an error if the drive is protected
 				except:
 					continue
 				else:
-					if target_filename in files:
-						upload_disk = os.path.join(os.sep, 'media', getpass.getuser(), drive) + os.sep
+					if target_filename in filenames:
+						if not target_file_found:
+							upload_disk = '/Volumes/' + drive + '/'
 						target_file_found = True
-						break
-		#
-		# set upload_port to drive if found
-		#
 
+		#
+		# Set upload_port to drive if found
+		#
 		if target_file_found or target_drive_found:
-			env.Replace(
-				UPLOAD_FLAGS="-P$UPLOAD_PORT"
-			)
+			env.Replace(UPLOAD_PORT=upload_disk)
+			print('\nUpload disk: ', upload_disk, '\n')
+		else:
+			print_error('Autodetect Error')
 
-	elif current_OS == 'Darwin':  # MAC
-		#
-		# platformio.ini will accept this for a OSX upload port designation: 'upload_port = /media/media_name/drive'
-		#
-		drives = os.listdir('/Volumes')  # human readable names
-		if target_drive in drives and not target_file_found:  # set upload if not found target file yet
-			target_drive_found = True
-			upload_disk = '/Volumes/' + target_drive + '/'
-		for drive in drives:
-			try:
-				filenames = os.listdir('/Volumes/' + drive + '/')   # will get an error if the drive is protected
-			except:
-				continue
-			else:
-				if target_filename in filenames:
-					if not target_file_found:
-						upload_disk = '/Volumes/' + drive + '/'
-					target_file_found = True
+	except Exception as e:
+		print_error(str(e))
 
-	#
-	# Set upload_port to drive if found
-	#
-	if target_file_found or target_drive_found:
-		env.Replace(UPLOAD_PORT=upload_disk)
-		print('\nUpload disk: ', upload_disk, '\n')
-	else:
-		print_error('Autodetect Error')
-
-except Exception as e:
-	print_error(str(e))
+env.AddPreAction("upload", before_upload)

Marlin/src/HAL/LPC1768/usb_serial.cpp

@@ -29,8 +29,8 @@
 
 EmergencyParser::State emergency_state;
 
-bool CDC_RecvCallback(const char buffer) {
-  emergency_parser.update(emergency_state, buffer);
+bool CDC_RecvCallback(const char c) {
+  emergency_parser.update(emergency_state, c);
   return true;
 }
 

Marlin/src/HAL/NATIVE_SIM/HAL.h

@@ -0,0 +1,217 @@
+/**
+ * Marlin 3D Printer Firmware
+ *
+ * Copyright (c) 2021 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ * Copyright (c) 2016 Bob Cousins bobcousins42@googlemail.com
+ * Copyright (c) 2015-2016 Nico Tonnhofer wurstnase.reprap@gmail.com
+ *
+ * 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/>.
+ *
+ */
+#pragma once
+
+#define CPU_32_BIT
+#define HAL_IDLETASK
+void HAL_idletask();
+
+#define F_CPU 100000000
+#define SystemCoreClock F_CPU
+#include <stdint.h>
+#include <stdarg.h>
+
+#undef min
+#undef max
+
+#include <algorithm>
+#include "pinmapping.h"
+
+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
+#define OCT  8
+#define BIN  2
+//arduino: binary.h (weird defines)
+#define B01 1
+#define B10 2
+
+#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
+
+extern MSerialT serial_stream_0;
+extern MSerialT serial_stream_1;
+extern MSerialT serial_stream_2;
+extern MSerialT serial_stream_3;
+
+#define _MSERIAL(X) serial_stream_##X
+#define MSERIAL(X) _MSERIAL(X)
+
+#if WITHIN(SERIAL_PORT, 0, 3)
+  #define MYSERIAL1 MSERIAL(SERIAL_PORT)
+#else
+  #error "SERIAL_PORT must be from 0 to 3. Please update your configuration."
+#endif
+
+#ifdef SERIAL_PORT_2
+  #if WITHIN(SERIAL_PORT_2, 0, 3)
+    #define MYSERIAL2 MSERIAL(SERIAL_PORT_2)
+  #else
+    #error "SERIAL_PORT_2 must be from 0 to 3. Please update your configuration."
+  #endif
+#endif
+
+#ifdef MMU2_SERIAL_PORT
+  #if WITHIN(MMU2_SERIAL_PORT, 0, 3)
+    #define MMU2_SERIAL MSERIAL(MMU2_SERIAL_PORT)
+  #else
+    #error "MMU2_SERIAL_PORT must be from 0 to 3. Please update your configuration."
+  #endif
+#endif
+
+#ifdef LCD_SERIAL_PORT
+  #if WITHIN(LCD_SERIAL_PORT, 0, 3)
+    #define LCD_SERIAL MSERIAL(LCD_SERIAL_PORT)
+  #else
+    #error "LCD_SERIAL_PORT must be from 0 to 3. Please update your configuration."
+  #endif
+#endif
+
+
+#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() {}
+
+// Utility functions
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-function"
+int freeMemory();
+#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
+
+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();
+
+// Reset source
+inline void HAL_clear_reset_source(void) {}
+inline uint8_t HAL_get_reset_source(void) { return RST_POWER_ON; }
+
+/* ---------------- Delay in cycles */
+
+#define DELAY_CYCLES(x) Kernel::delayCycles(x)
+#define SYSTEM_YIELD() Kernel::yield()
+
+// Maple Compatibility
+typedef void (*systickCallback_t)(void);
+void systick_attach_callback(systickCallback_t cb);
+extern volatile uint32_t systick_uptime_millis;
+
+// Marlin uses strstr in constexpr context, this is not supported, workaround by defining constexpr versions of the required functions.
+#define strstr(a, b) strstr_constexpr((a), (b))
+
+constexpr inline std::size_t strlen_constexpr(const char* str) {
+  // https://github.com/gcc-mirror/gcc/blob/5c7634a0e5f202935aa6c11b6ea953b8bf80a00a/libstdc%2B%2B-v3/include/bits/char_traits.h#L329
+  if (str != nullptr) {
+    std::size_t i = 0;
+    while (str[i] != '\0') {
+      ++i;
+    }
+
+    return i;
+  }
+
+  return 0;
+}
+
+constexpr inline int strncmp_constexpr(const char* lhs, const char* rhs, std::size_t count) {
+  // https://github.com/gcc-mirror/gcc/blob/13b9cbfc32fe3ac4c81c4dd9c42d141c8fb95db4/libstdc%2B%2B-v3/include/bits/char_traits.h#L655
+  if (lhs == nullptr || rhs == nullptr) {
+    return rhs != nullptr ? -1 : 1;
+  }
+
+  for (std::size_t i = 0; i < count; ++i) {
+    if (lhs[i] != rhs[i]) {
+      return lhs[i] < rhs[i] ? -1 : 1;
+    } else if (lhs[i] == '\0') {
+      return 0;
+    }
+  }
+
+  return 0;
+}
+
+constexpr inline const char* strstr_constexpr(const char* str, const char* target) {
+  // https://github.com/freebsd/freebsd/blob/master/sys/libkern/strstr.c
+  if (char c = target != nullptr ? *target++ : '\0'; c != '\0' && str != nullptr) {
+    std::size_t len = strlen_constexpr(target);
+    do {
+      char sc = {};
+      do {
+        if ((sc = *str++) == '\0') {
+          return nullptr;
+        }
+      } while (sc != c);
+    } while (strncmp_constexpr(str, target, len) != 0);
+    --str;
+  }
+
+  return str;
+}
+
+constexpr inline char* strstr_constexpr(char* str, const char* target) {
+  // https://github.com/freebsd/freebsd/blob/master/sys/libkern/strstr.c
+  if (char c = target != nullptr ? *target++ : '\0'; c != '\0' && str != nullptr) {
+    std::size_t len = strlen_constexpr(target);
+    do {
+      char sc = {};
+      do {
+        if ((sc = *str++) == '\0') {
+          return nullptr;
+        }
+      } while (sc != c);
+    } while (strncmp_constexpr(str, target, len) != 0);
+    --str;
+  }
+  return str;
+}