[BUG] GD32F303RE_creality_mfl - Incorrectly extruded infill on board install

[neoscorpi0]

Did you test the latest bugfix-2.1.x code?

Yes, and the problem still exists.

Bug Description

I've got an Ender 3 Max that I recently installed a GD32F303 (T8) board into vs the original one it came with (STM32 4.2.2 A/P) to use the quiet stepper drivers (TMC2208s) and despite flashing and printing correctly I am having (Hardware?) under extrusion issues (Only) with print infill. This problem did not exist on my previous 4.2.2 board and I am printing with the same firmware settings, slicer settings and filament.

This is like the outer walls of the prints printing perfectly but for some reason all infills are incorrectly printing. For instance I can print a XYZ calibration cube (Which have been my tests) however despite the outer walls extruding and printing correctly the infill will under extrude and look all stringy and/or barely print at all. Happy to attach some screens of failed XYZ cube prints after installing the new board.

I am using Marlin Auto Build to build the firmware and have successfully flashed and reproduced the problem with both STM32 and GD32 environments flashing each separately to the GD32F303RET6 board.

I was able to get both environments (STM32 & GD32) working on the GD32F303 board so if it's possible that one of them is causing issues that you're able to spot I'm happy to flash the alternative firmware on as well as make changes to check various settings (At this stage it looks like flashing the STM32 environment on the GD32 board is working better given the huge amount of issues even getting the GD32 environment working however whatever suggestions you could offer to help solving this would be appreciated.

I have created a build folder of each Marlin build as well as a list of every change made with the different firmware builds.

Bug Timeline

When installing a GD32F303RET6 board to replace stock Ender 3 Max board

Expected behavior

I expected the infill to print and/or extrude correctly and at the same rate as the walls of the print.

Actual behavior

The walls of the print print perfectly however the infill is a stringy mess looking to be under extruding default correct eSteps.

Steps to Reproduce

1. Lowered my build size by removing custom features I had added like a custom boot screen - Problem was much more severe with a Custom Boot Screen however still occurs.
2. Flashed GD32 Board with STM32 Environment - Problem still occurs
3. Flashed GD32 Board with GD32 Environment - Problem still occurs
4. Checked eSteps, both changing to stock value and recalibrating - Problem still occurs
5. Slowly increased and decreased the extrusion rate while printing - Problem still occurs
6. Printed with a different slicer (Creality Slicer & Cura) in an attempt to replicated issue - Printer Freezes and goes unresponsive (GD32 Default Envs)

Version of Marlin Firmware

2.1.3b

Printer model

Ender 3 Max

Electronics

GD32 board as above vs stock STM32 board (Trying to get going)

LCD/Controller

CR10 Stock Display

Other add-ons

CRTouch

Bed Leveling

ABL Bilinear mesh

Your Slicer

Other (explain below)

Host Software

OctoPrint

Don't forget to include

• A ZIP file containing your Configuration.h and Configuration_adv.h.

Additional information & file uploads

I've upload configuration.h and configuration.adv.h from both by STM32 build and my GD32 board as well as the compiling instructions I followed in VSCode for each.

I've also added some screenshots as examples of the problem I'm having.

Example Calibration Cubes.zip
GD32 Configurations.zip
STM32F Configurations.zip

[ellensp]

The firmware makes no distinction between say a wall extrusion vs a infill extrusion. Its the same gcode a G1

[neoscorpi0]

Hey, thanks for your comment. I was only able to get the board working with the GD32 default_envs from following your post here.

#27795

I would've assumed the same? I talked to my friend and he was stumped too suggesting eSteps and flowrate which I checked & recalibrated. There were other issues other than the infill not printing as it should like the printer extruder stepper motor stopping working entirely while printing which happened several times.

Due to the above, I'm assuming the problem lies with the extruder stepper driver or configurations to it (After going from a the AR4988 stepper driver with my original board to the TMC2208_STANDALONE with the GD32 board) Could it be that the problem causing the extruder motor to either not print or extrude incorrectly is caused by the stepper driver being different? (I've tried to flash the board with the AR4988 driver for the extruder after checking backwards compatibility when the extruder motor was stopping during printing however still ran into the same issue.

I've had this problem ever since swapping in the GD32 board in in an attempt to utilise the quieter stepper motor drivers. I'm not actually sure what to do at this stage except swap the old 4.2.2 STM32F103RET6 (A/P) board back in.

This is the issue I'm having and the suggested fix:

Firmware Incompatibility (GD32 vs. STM32)
Many GD32 chips are clones of the STM32F103 but have slight timing differences. If you flashed firmware compiled for an STM32 (like standard Marlin 2.0/2.1), the extruder may fail to move or behave erratically because the GD32's internal clocks or licensing restrictions aren't officially supported in older standard builds.

Could this be a timing issue? I haven't adjusted the timing at all (Except for the LCD clock as per your post) from 72MHz despite reading posts that the GD32 runs at a higher CPU clock speed (108MHz?)

If there's anything you can suggest that I may not have checked I'd be happy to try it, otherwise thanks for your help all the same :)

Update: I've just had a quick search this morning and Creality have the source code for the GD MCU available here however the source code is for Marlin 2.0.8.x, do you know how I would see the differences between the compilations if I were to flash 2.1.3b with the changes made here without examining every file or the specific files I'd have to look at?

Thanks :)