AnsweredAssumed Answered

Virtual com port driver problems

Question asked by belchamber.ian on Jan 14, 2016

We have had a product released for a little while that has been working well, with a STM32F4 communicating to a PC over virtual com port. We have had some issue recently so I am revisiting this.

The first thing I came across was (running from windows 10 64 bit) I can send bytes, and I get the receive event, but when I go to read the bytes I got ""error reading comm device" 8020"

We were using an old vcp driver, 1.3. So I got the new one, 1.4. This does something strange: If I just plug my device in, I get:
Ports(Com & LPT): USB Serial Device(COM4) and it looks ok,

But if I restart my device while the USB is connected, I get:

Other devices: STM32 Virtual Comport in FS Mode 
Ports(Com & LPT): USB Serial Device(COM5) , both with yellow warning triangle.

(yes, the comport number changed from 4 to 5)

Any clues as to what is happening here? Does vcp work on win 10 64 bit?