Hi there, I'm here about a BM16a PCB order that I'm having trouble working with. I ordered it on June 12, 2023 through AliExpress, order ID 8169717183389187.
Symptoms:
- LEDs don't light up when plugged in
- Keystrokes are not issued when pins are shorted
- Device is not recognised as a USB device at all
- Unable to flash through QMK as it is not recognised through dfu-utils. Plugging in with the bootmagic button shorted does not work. Using the RST button does not work.
- Device is not listed through lsusb -t
- On Windows, a sound is made when the device is connected, but the device is not recognised
- When the RST button is pressed, the device does reset, but that doesn't fix the issues.
When the device is plugged in, and whenever the RST button is pressed, I receive the following output from dmesg:
[11908.719454] usb 1-3: new full-speed USB device number 46 using xhci_hcd
[11908.849491] usb 1-3: device descriptor read/64, error -71
[11909.085970] usb 1-3: device descriptor read/64, error -71
[11909.316138] usb 1-3: new full-speed USB device number 47 using xhci_hcd
[11909.446200] usb 1-3: device descriptor read/64, error -71
[11909.682565] usb 1-3: device descriptor read/64, error -71
[11909.789331] usb usb1-port3: attempt power cycle
[11910.192892] usb 1-3: new full-speed USB device number 48 using xhci_hcd
[11910.193009] usb 1-3: Device not responding to setup address.
[11910.399234] usb 1-3: Device not responding to setup address.
[11910.606120] usb 1-3: device not accepting address 48, error -71
[11910.729321] usb 1-3: new full-speed USB device number 49 using xhci_hcd
[11910.729431] usb 1-3: Device not responding to setup address.
[11910.936298] usb 1-3: Device not responding to setup address.
[11911.142510] usb 1-3: device not accepting address 49, error -71
[11911.142634] usb usb1-port3: unable to enumerate USB device
Things I have tried:
- Different USB ports
- Different USB cables
- Different ways to short the pins (tweezers, cable, scissors, paperclip)
- Different operating systems (Linux, Windows)
Since the RST button works, I don't think the device is dead. I suspect this is what is happening is that there's something wrong with the bootloader, since the STM32F103 ROM seems to only support flashing through serial. The QMK docs explain the situation: https://github.com/qmk/qmk_firmware/blob/master/docs/isp_flashing_guide.md#flashing-stm32duino-bootloader