Custom G-code input

[LMoesman]

Hello there 👋,

I am having some trouble with the custom G-code input feature. When I just flashed my mainboard everything works fine and I am able to use the custom G-code input screen. But when I reboot my printer I can't access the screen anymore, it gives me a status message to "GUI/OS update required" which I already did before flashing my mainboard and confirmed because I could access it before. I looked into the marlin firmware and found out that after a fresh firmware install the board was able to read the os and gui version from the display, but after a reboot it came back with os version 0 and gui version 0 (logged the versions to the serial console). I edited the code a bit to force a check of the os and gui version when pressing the button on the screen and after a manual called check it was able to read the versions again and access the screen after a second tap on the G-code input button.

Do you maybe have any idea what is causing this issue? I hope you may have an idea, that may help me fix the problem.

[Desuuuu]

I'm not sure but I think I've had this happen a while ago while using the DGUS serial tool to directly communicate with the touchscreen. Sadly, I have no idea why this happened, or how I got around it...

Does it happen often?

[LMoesman]

At the moment it only works when I reset the EEPROM or after I flash Marlin again to my printer board (which also causes a EEPROM reset I found out). When i reboot it afterwards it doesn't work anymore. But I may have to search for a solution outside of Marlin since you had the same problem with the serial tool

[Desuuuu]

It might have been a bug in their software too.

I suspect Marlin might not be receiving a response to the version read in your case.

I'm wondering if the problem could be timing-related, as the read call for the versions is sent pretty early on.

Could you try applying this patch to Marlin and trying again?

diff --git a/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp b/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp
index 1d97902c71..6c8679e011 100644
--- a/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp
+++ b/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.cpp
@@ -57,7 +57,7 @@ void DGUSDisplay::Loop() {
 void DGUSDisplay::Init() {
   LCD_SERIAL.begin(LCD_BAUDRATE);
 
-  Read(DGUS_VERSION, 1);
+  ReadVersions();
 }
 
 void DGUSDisplay::Read(uint16_t addr, uint8_t size) {
@@ -158,6 +158,12 @@ void DGUSDisplay::WriteStringPGM(uint16_t addr, const void* data_ptr, uint8_t si
   }
 }
 
+void DGUSDisplay::ReadVersions() {
+  if (gui_version != 0 && os_version != 0) return;
+
+  Read(DGUS_VERSION, 1);
+}
+
 void DGUSDisplay::SwitchScreen(DGUS_Screen screen) {
   DEBUG_ECHOLNPGM("SwitchScreen ", (uint8_t)screen);
   const uint8_t command[] = { 0x5A, 0x01, 0x00, (uint8_t)screen };
diff --git a/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.h b/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.h
index 332108d81a..9e56ec30ab 100644
--- a/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.h
+++ b/Marlin/src/lcd/extui/dgus_reloaded/DGUSDisplay.h
@@ -69,6 +69,8 @@ public:
   // Until now I did not need to actively read from the display. That's why there is no ReadVariable
   // (I extensively use the auto upload of the display)
 
+  static void ReadVersions();
+
   // Force display into another screen.
   static void SwitchScreen(DGUS_Screen screen);
   // Play sounds using the display speaker.
diff --git a/Marlin/src/lcd/extui/dgus_reloaded/DGUSScreenHandler.cpp b/Marlin/src/lcd/extui/dgus_reloaded/DGUSScreenHandler.cpp
index 17e7a38445..829385574d 100644
--- a/Marlin/src/lcd/extui/dgus_reloaded/DGUSScreenHandler.cpp
+++ b/Marlin/src/lcd/extui/dgus_reloaded/DGUSScreenHandler.cpp
@@ -113,6 +113,8 @@ void DGUSScreenHandler::Loop() {
   if (!booted && ELAPSED(ms, 3000)) {
     booted = true;
 
+    dgus_display.ReadVersions();
+
     if (current_screen == DGUS_Screen::BOOT) {
       MoveToScreen(DGUS_Screen::HOME);
     }
diff --git a/Marlin/src/lcd/extui/dgus_reloaded/DGUSSetupHandler.cpp b/Marlin/src/lcd/extui/dgus_reloaded/DGUSSetupHandler.cpp
index 090d53c92e..afdb48651c 100644
--- a/Marlin/src/lcd/extui/dgus_reloaded/DGUSSetupHandler.cpp
+++ b/Marlin/src/lcd/extui/dgus_reloaded/DGUSSetupHandler.cpp
@@ -187,6 +187,7 @@ bool DGUSSetupHandler::Gcode() {
 
   if (dgus_display.gui_version < 0x30 || dgus_display.os_version < 0x21) {
     dgus_screen_handler.SetStatusMessage(FPSTR(DGUS_MSG_FW_OUTDATED));
+    dgus_display.ReadVersions();
     return false;
   }

[LMoesman]

It works! The ReadVersions call in DGUSSScreenHandler did the trick, thank you so much!

[LMoesman]

Do you mind if I try to submit a PR to Marlin with this patch? I will link to this discussion as a reference of course, if it's okay

[Desuuuu]

Please do!