PrintFxv2

README.md

@@ -179,6 +179,11 @@ the widest roll it will accept — the console warns you if you enter anything w
 | DK-11208 | 38 × 90 mm die-cut | Narrower; turn the photo off |
 | DK-11209 | 29 × 62 mm die-cut | Name and host only |
 
+**A DK-22251 must be set as the black/red roll even if nothing on the badge is red.** The printer
+refuses a monochrome job on two-colour tape, saying *Black/Red on White paper is installed now.
+Change it to Monochrome media.* The roll setting controls how the job is built, not just its
+colour.
+
 **Tell it which roll is loaded.** *Roll loaded in the printer* under **Sites → Edit → Printer**
 must match what is physically in the machine. A two-colour job sent to a plain roll is refused
 outright: the printer shows **Wrong Roll Type** and nothing comes out. The setting is separate
@@ -223,8 +228,14 @@ docker compose exec visitor-signin node scripts/printer-status.mjs
 ```
 
 It reports the media width, whether the roll is continuous or die-cut, any error the printer is
-holding, and the roll id that matches. `brother_ql`'s network backend only writes to the socket
-and never reads, which is why a refused job still looks like a success — this asks directly.
+holding, and the roll id that matches.
+
+**It does not work on every printer.** Many Brother network print servers are write-only on port
+9100: they accept jobs but never answer a status request, even though the same printer reports
+happily over USB. The QL-820NWB is one of them. When that happens, **Brother Status Monitor on a
+PC with the printer installed is the thing to use** — it gives the exact reason a job was refused,
+in plain words, which is more than anything on the server can tell you. `brother_ql`'s network
+backend never reads the socket at all, so it reports success no matter what the printer does.
 
 If the printer will not answer, work through the possibilities one at a time: