Anet ET4 updating mcu

General Discussion
1

Hi, kind folks. I’m already running klipper on my Anet ET4 (+, pro, I get confused by the submodels, but it has a capacitive sensor).

I’m trying to update the MCU for the first time since the initial flash and finding I can no longer connect with the ST-Link utility. “Can not connect to target” is what it says. I verified all the jumpers are installed correctly (they’re not in the same order as the images I found online as I guess my ST-LINK V2 stick has them in a different order. Drivers are installed correctly. USB stick has the latest firmware. Printer is on when I’m trying to connect.

If anyone has any help to offer, I’d really appreciate it. I feel like maybe I need to drop to a bootloader that maybe I no longer have, but maybe there’s a way to force the board into a programming mode again.

Thanks so much.

2

Bit late I know but this is for me in the future and any others who need to info when they want to reflash a anet et4 board.
The trick to get the stlink to connect is to hold down the white reset button and then release it when you press connect in STM32cubeprogrammer.

Edit: You also need to put the board into DFU mode by pressing on the screen while turning the machine on. Then you can connect with the reset button.

3

You’re a good human for posting the solution to a long-ago problem for future searches!

I solved the problem by upgrading to an SKR Pico, but it’s good to know the old Anet board in my spare parts bin isn’t without use.