I've managed to compile a working firmware with this config: https://github.com/gleber/qmk_firmware/commit/54078ec73c0ff2bd01984242f748a837c1954d03
This isn't tested much, just the basics: keys and split setup. LED, bootloader magic key and any other features are not yet implemented. Tested only the Miryoku layout so far.
I've disassembled it and found a few things.
Back of one of the sides looks like this:
A more close up photo of the chip shows some STM32 chip:
If you decode the QR code it gives you a short link to what seem to be JLC PCB page about this specific PCB:
- right: https://m-9.cn/2kx9vqhz04xv
- left: https://m-9.cn/2kx9vqu40dft
It includes product name 【X.Tips】X7S小分体键盘_-_V2.0_【热插拔】PCB-X7S-V2-R__20240726163326 which translates with Google Translate to 【X.Tips】X7S small split keyboard_-_V2.0_【Hot plug】PCB-X7S-V2-R__20240726163326
And these schematics images for the right side:
and for the left side:
Attached via-x7.json file was sent to one of the buyers by the seller. It works for my keyboard.
@kyonav Thanks for the tutorial too! I had similar results than @GreyTime, in Linux in my case.
I am able to flash the bootloader with both STM32CubeProgrammer as well as with st-flash.
Once flashed through the ST-link v2, I disconnect and connect through the USB, and it is recognized as Maple (0x1eaf:0x0003).
In this state,
dfu-util -ldetects the device and recognizes 3 interfaces. However, when I try to flash QMK firmware (any .bin), it complains that it cannot set the alternate interface:I tried the maple_rev3, with similar results.
With the generic_boot20_pc13.bin firmware, the device was recognized as a USB modem, and dfu-util didn't detect it.
Then, I tried rebooting shorting the bootloader pins, and I got the "Unable to enumerate" error.
Finally, I tried flashing the firmware directly with STM32CubeProgrammer and with st-flash, which completed successfully, but then produced the same "Unable to enumerate USB device". Shorting the pins, don't make a difference.
I think it's a bit striking than after flashing the maple bootloader and shorting the pins produces the same "bricked" state (while the pins are shorted), as than flashing the QMK firmware through ST-link.