STM32F407ZGT6 virtual com port error 43

[Serjey Bugayov]

Posted on June 15, 2017 at 13:13

Hello everybody! Can anybody say to me what I've do wrong:I have a development board based on STM32F407 ZGT6 (buy here: 

https://ru.aliexpress.com/item/STM32F407ZGT6-Development-Board-ARM-M4-STM32F4-cortex-M4-core-Board-Compatibility-Multiple-Extension/32795142050.html?spm=2114.13010608.0.0.4h8JMA

 ) and trying to use virtual com port on it. But every time I connected it to my both windows10 PCs(one 32 and another 64 bit)  I have an error #43:

Windows has stopped this device because it has reported problems. (Code 43)

A request for the USB device descriptor failed.

I already have installed VCP official driver and tested good work with other stm32 MCUs (stm32f103).

The pin out also might be good because I test communication on oscilloscope but I'm not sure at all (PA12 was 3.2V and PA11 was about 0). And when i change usb mode to DFU the PC can recognized MCU as DFU mode.

I have'n such enough experience with it and can't understand what goes wrong.

I use CubeMX with Keil Uvision.

Code is simple: I include to 'main.c' file -'usbd_cdc_if.h' and use that function CDC_Transmit_FS()

[Serjey Bugayov]

Posted on June 18, 2017 at 19:33

Thanks everybody for your attention but it seems that I find out of my board problem. Dear china friend solder 1.5k resistor between DP and +3.3 but not solder anything between Vbus and MC. Also he forgot to solder usb ID to anywhere where it needed. Using CubeMx there is checkbox in Configuration frame named 'VBUS sensing' by default it's checked. I have not paid attention on it at and it cause to not working usb device mode. Simply unchecked it gives working MK and a lot of happiness=)