li bao

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6 years, 4 months ago.

USBSerial don't work, PC can not identify USB device, prompting "device descriptor request failed."

STM32 F103C8 WIN 10 I tested various examples of USBDevice, USBMouse, USBMSD and so on. How to modify it? Is it a board problem or an operating system problem?

1 Answer

Zoltan Hudak
6 years, 4 months ago.

Hello Li,

You can try this demo. But please be aware that the USB device to work the USB DP pin (PA_12) shall be connected to VCC over a 1.5k resistor. Otherwise the host PC won't recognise the USB device and the USB device library code will hang. Since the STM32F103C8T6 (Blue Pill) board) is equipped with a 10k one (which could work in some cases), try to connect an additional 1.8k resistor between the PA_12 and +3.3V pins.

thanks a lot! I test this demo, it's not work too. I tested this board on framework-arduinoststm32(maple), the USBSerial work well,

posted by li bao 28 Jun 2018

when I set the USB VID and PID as same as arduinoststm32(maple) driver,it work!

posted by li bao 28 Jun 2018