2016-06-16 10:19 AM
hi,I am tring to use usb virtual port to transmit data to pc.
MCU:STM32F373 100pinscubemx: usb device fs checkedusb:communication device classPC: windows 10heap size: 0x200stack size :0x400when i plug usb cable to pc,it can not be recognised.In device manager,it shows Device Descriptor Request Failed. ST VCP driver installed. BTW, when I debug it, it could goes into USB_LP_IRQHandler after MX_USB_DEVICE_Init() excuted.thanks.2017-09-18 10:55 AM
I can confirm that this works for me on STM32F407 / STM32F4-Discovery.
My setupPins / MiddleWares
USB_Device / Class for FS IP = Communication Device Class..RCC / HSE = Crystal/Ceramic
USB_OTG_FS / Mode=Device_OnlySYS / Timebase Source = SysTick
(USB_OTG_HS Disabled)Clocks
As above (PLL_M 8, N 336, P 2, Q 7)
For me the key was setting the 8Mhz and PLL_M=8. CubeMX had for some reason defaulted to 25Mhz / PPL_M=25 that I did not notice.
/Teemu2017-11-14 01:10 AM
Hello, when I active usb DMA, my board isn't recognized by host. So I suspect DMA in the configuration. Without DMA, virtual serial com port run very well.
2018-01-26 09:22 PM
This turned out to be the solution to my 'Device descriptor request failed' problem as well.
One more thing I would like to add which was also a problem: I had upgraded the software package for STM32F4 (to V1.19), and CubeMX asked if I wanted to migrate the project to the new package, I clicked yes. The usb CDC did not work until I restarted the project from scratch, with the new STM32F4 package.
2018-03-14 12:54 AM
Hi, All!
I have: HAL version 1.0.0 and SPL)
I just adjusted descriptor:
0x02, /*bDeviceClass*/
0x02, /*bDeviceSubClass*/It's work on Win10!
2018-04-13 01:27 PM
I had this issue and found it was the micro-USB Cable. After switching cables the USB worked fine.
Make sure you cut the malfunctioning cable into small pieces to prevent future issues with it.
I have an F407G-Disc1, F411-disco, and F429i-disc1 that all worked after switching cables.