Configurations/config/examples/Anet/ET4-Pro

Marlin for Anet ET4/ET5 Series

A debugging/programming probe (e.g., ST-Link, J-Link, or Black Magic Probe) is required to flash the the OpenBLT bootloader for Anet ET4/ET5 series printers due to incompatibility with the stock bootloader. Once OpenBLT is flashed, Marlin can be updated by SD card just like the original firmware.

Flashing OpenBLT Bootloader with an ST-Link V2

1. Using three female to female Dupont jumper cables, connect GND, SWDIO, and SWCLK pins from the ST-Link to the Serial Wire Debug (SWD) header on the motherboard. Pay close attention that the cables on SWD header side match the order below using the U and G letters printed on the motherboard as a reference:

     SWD Header on ET Series motherboard
        ___
     U | o |  (not connected)
       |---|
       | o |  SWDIO
       |---|
       | o |  SWCLCK
       |---|
     G | o |  GND
        ---
   

   Photo reference:

   

   GND is connected to GND (black wire), SWDIO to SWDIO (yellow wire), and SWCLK to SWCLK (green wire). Your ST-Link pinout may differ from the one pictured, so double-check pinout.

2. Plug in the ST-Link to your computer's USB port & power on your printer.

3. Download & install STM32 ST-Link Utility.

4. Launch STM32 ST-Link Utility & click Target then Connect.

5. Backup the original motherboard firmware or, at the very least, back up the bootloader. This will allow you to recover the full stock firmware by flashing the original bootloader to the 0x08000000 - 0x8010000 address range, and flashing any of the available Anet firmware binaries (e.g., et4.bin, et5.bin, etc.) to address 0x08010000. Note: You can restore your motherboard to stock by downloading printer-specific firmware from Anet's Download section and flashing the included hex (e.g., et4p20191211V1.0.2.hex, et520200612V1.1.7.hex, etc.) to address 0x08000000.

6. Download & extract OpenBLT bootloader for Anet ET4/ET5 series printers.

7. Click on Target then Program...

8. Set the Start Address to 0x08000000.

9. Under File Path, click Browse and select openblt_et4.bin extracted in Step 6.

10. Click Start to initiate the flashing process.

11. OpenBLT for Anet ET4/ET5 series printers is now be installed on your motherboard.

Installing Marlin

1. Once Marlin is compiled, copy Marlin/.pio/build/Anet_ET4_OpenBLT/firmware.srec to a blank SD card and insert it into your printer.
2. Power cycle your printer to start the update process.

Acknowledgements

• @davidtgbe for porting Marlin to the ET4/ET5 series.
• Telegram Anet ET4 spanish group, especially @olidnon, who lent his motherboard for testing.
• @uwe and @mubes from Black Magic Probe team, and to @Ebiroll (BMP/ESP32).
• All contributors and testers.