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7 years, 1 month ago.
STM32F401RE Nucleo - Virtual COM Port is not working properly
I've been using the Nucleo for some time, and I found out there is a problem with the VIrtual COM port. I used a sample test program from the library (printf) and any of the terminal software I've used does not show any output despite the Virtual COM Port is detected. However, when I used an external USB->UART converter (available cheaply in your local stores), and jumper the converter's RX pin to the CN3's RX pin, I see the output clearly. The funny thing is, is the CN3's RX pin a TX pin? I felt that this has printed wrongly on the board.
Here's the steps I've done:
1.) Installed the Virtual COM Port Drivers (VCP 1.3.1) and reinstalled it. 2.) Tested with all different libraries of printf, and it didn't do much - detected but not getting outputs or inputs.
Is the UART module in the ST-Link on the board not working? Or did I miss something here?
Question relating to:
5 years, 1 month ago.
Have the same problem with two NECLEO boards - F401RE and F103RB. Simptoms are the same - i can send letters from terminal through virtual com port and nothing comes out of virtual com port. Used oscilograph to track signals and all seems correct on CN3 connector, so all signals are going to V-Link part, USB sniffer shows that no packets at all are coming from virtual com port. Tried to reinstall drivers and upgrade firmware. Now I can only use this boards connecting PL2303 converter to Serial1 or Serial2 pins - all is ok at high speeds. But this is not very convenient to have two USB connections - one for programming and one for debug terminal.
So long as this problem is the same for two differecnt NUCLEO boards (bought from SeeedStudio half year ago), it looks like some open V-Link firmware or driver problem.
Update: tried it on PC with x86 Win7 and it fully works. So this problem with high probability can be localized to amd64 driver version.
7 years, 1 month ago.
I'm not using the VCP 1.3 drivers, the Nucleo board has it's own driver set, and the USART connection is working fine on the F401RE board.
Using Win7 x64, reporting in Device Manager - Ports
STMicroelectronics STLink Virtual COM Port (COM12)
Also install the current firmware (2.19.3) for the Nucleo ST-LINK
6 years, 1 month ago.
Hello. I have the same problem in linux. The Serial pc comunications works 1/10 or even less. Sometimes it works. The rest of functions look work properly.
5 years, 3 months ago.
It doesn't appear that the ST USB Composite drivers work when the F401RE is plugged into a USB3.0 port. Seems to work fine in a USB2.0 port only. All other drivers load properly on a USB3.0 port.