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Graduate
September 9, 2025
Question

STM32F4xx example project FreeRTOS+CLI with USB virtual com port

  • September 9, 2025
  • 2 replies
  • 429 views

Is there an STMF4xx example project I can reference for using a virtual COM port to connect to FreeRTOS+CLI? I tried to do this myself by having the FreeRTOS+CLI function _write() call CDC_Transmit_FS() and by having CDC_Receive_FS() call a function that puts the received data into a circular queue, and then calls vTaskNotifyGiveFromISR() to tell the CommandConsoleTask that there is data in the queue for it to process.

I see CDC_Transmit_FS() being called, but a breakpoint in CDC_TransmitCplt_FS() never fires, and no data appears in a Tera Term window connected to the serial port labeled as STMicroelectronics STLink Virtual COM Port (COM4). Likewise, typing into the Tera Term window does not result in a breakpoint in CDC_Receive_FS() ever getting hit.

I'm sure I'm doing something fundamentally wrong, but what?

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    2 replies

    Explorer
    September 10, 2025

    Tera Term can be connected to the serial port labeled as STMicroelectronics STLink Virtual COM Port. There are separate pins configured to connect using virtual com port. Tera term is connected to one of the uart configuration.

    You can check using other virtual com port.

    Graduate
    September 10, 2025

    That much I already figured out. My question is about an example project I can use to see how the embedded side works, so that I can connect the command task to the virtual COM port.

    Super User
    October 8, 2025
    Technical Moderator
    October 8, 2025

    Hello @jlthompson 
    If you still need help on this topic,

    You can refer to this knowledge base article, which explains how to integrate and use the FreeRTOS™ command-line interface (CLI) library.

    You can also search GitHub for existing projects on this subject.

    Gyessine