How to Reuse Creality 32bit 4.2.2 Mainboard+LCD As an Arduino

One of the most poppular budged 3D Printer is probaly creality ender3 and for those who recenly purchase will recive an 32bit 4.2.2 non-silence mainboard which quickly become anoying so most people just replace it. And here we are puting perfectly good mainboard to drawer waiting to make somthing usefull out of it. I mean look at it the board got 4 srepper driver 3 mosfet out put channel and it powered by an powerfull stm32f103ret6 it an 32 bit arm M3 microcontroller.

Big red flag : Doing this can risk burning your board and may ruined your stock bootloader which means your won't take firmware from sd card like normal any more.

Soldering iron, wire, flux, skill

ST-link V2

STM Cube Programmer download here

Any creality 4.2.2 firware download here

visual studio code dowmload here and here is how to setup platformio

My shemetic and test firmware

Bottom one is SWD communication for your st-link

Upper one is P3 (reset) pin and next to it is gnd

All pin are lebeled both on board and st-link

board st-link

vcc to 3.3V

SWDIO to SWDIO

SWCLK to SWCLK

gnd to gnd

Short 2 pin upper header(green jumper) together (P3 reset to gnd)

BTW don't connect any thing to pc yet.

And nothing is else is connected even 24V input isn't connected)

1.Connect your st-link v2 to your pc

2.Hit refresh button (red circle on 1st pic)

3.config every thing up just like 1st pic (serial number will be differrent)

4.Click connect.

5.Quickly disconnect uppper 2 pin green jumper (P3 reset and gnd)

6.You see read data successfully at the bottom like 2nd pic.

7.Follow 3rd pic then you should see successfull message pop up.

8.Follow 4th pic by first click browse then select .bin file that you doloaded from creality then make sure you tick everything just like 4th pic then hit start program.

9.You should see bounch of successfull massage pop up and a core locked warning.

Verify every every thing by try my firmware in Visual studio code If all went well you should successfully upload my code (you should see massage at bottom like in the pic.

And when you connect your lcd screen and proper 12-24V supply voltage then turn rotary knob on lcd screen you should see hellow world! and a counter.

When you press rotary knob you should hear beep and if you connect stepper motor it should turn infinitly (make sure you change stepp config to sue you stepper by defualt it config for 3.75 degrees stepper change from 96 to 200 for 1.8 degrees steper)

Since now it work with arduino core you can just program as you like.

All Schemetic are included with firmware.

Feel free to leave a feedback or problems with the board.

I apologize for bad english I'm thai and english is not my main language.