Two Virtual COM Ports

moulay-hassan · ‎2016-05-11

Posted on May 11, 2016 at 13:01

Hello.

I made a code to send and receive data via USB bus based on the CubeMX CDC (Virtual COM Port).

Now I can emulate one virtual COM Port with STM32F407VGTx Discovery Board, but actually I'm thinking if I can emulate two Virtual COM Ports with the same Board.

Is there any possibility to do so ?

Thank you

mark239955_stm1 · ‎2016-05-11

Posted on May 11, 2016 at 13:07

Yes, it's possible to run two VCP's on an STM32F407.

moulay-hassan · ‎2016-05-11

Posted on May 11, 2016 at 13:12

Can you tell how can I do it please what libraries or what variables have I to modify to have two VCPs ?

mark239955_stm1 · ‎2016-05-12

Posted on May 12, 2016 at 11:23

I used Keil Pro (note: Pro, so quite expensive), about 6 months ago iirc. I just did it out of curiosity, I didn't put it to any use, and no, I don't have any notes. After managing to get both an MSC and a VCP working simultaneously, I realised that it might be possible for Keil to get two VCP's going instead, and it turned out that it can.

What it comes down to is that there are sufficient USB resources (endpoints) in an F4 to run up a composite USB device that enumerates as multiple devices.

I haven't looked at how to make that happen in CubeMX (or any other free libraries), or even if it's possible to get CubeMX to do it. I imagine that it should be.