I build a prototype board with a STM32G431KBT6 on it. This board simply drives some peripherals (led panel, motor) based on what commands I'm sending it over the Virtual COM port.
When connected to my laptop, I have a perfectly working prototype.
- I have USB enumeration
- I can send/receive commands over the VCP
- It perfectly drives the peripherals
But all this changes when I connect the prototype to my client's PC This PC isn't connected to the internet and probably can not find the right VCP port yet. But it should enumerate in my opinion. Nothing is shown in the device manager.
The weirdest thing of it all is that it also doesn't enumerate on my laptop and lab PC anymore
So basically as soon as my client's PC is connected to USB of the prototype, the device isn't recognized anymore.
So I thought, clearly there is something wrong with his USB cable, but when I connect an Arduino Nano on his USB cable, it is shown in device manager.
So how can Windows enumeration permanently damage the STM32 chip?
I did a full erase of the device and reprogrammed it, but nothings seems to work other then resolder a new chip.