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cdc problem

k b over 13 years ago

Hi,
I am trying to send data from AT91SAM7X256 to PC via virtual com port(usb)using cdc.I dont know how to do it exactly, I've tried keil example for cdc. And I used hyperterminal. But I could'nt see anything in hyperterminal. I don't know wich function use to send my data.
Thank you very much in advance

0 Chinzei Tsuneo over 13 years ago

Look in this part of the example code.
- VCOM_Serial2Usb() is repeatedly called in the while loop of vcomdemo() task
- In VCOM_Serial2Usb() routine, if CDC_DepInEmpty, serBuf[] is filled, and it is passed to the bulk IN endpoint using USB_WriteEP().

C:\Keil\ARM\Boards\Atmel\AT91SAM7X-EK\RL\USB\RTX_CDC\vcomdemo.c

void VCOM_Serial2Usb(void) {
  static char serBuf [USB_CDC_BUFSIZE];
         int  numBytesRead, numAvailByte;

  ser_AvailChar (&numAvailByte);
  if (numAvailByte > 0) {
    if (CDC_DepInEmpty) {
      numBytesRead = ser_Read (&serBuf[0], &numAvailByte);

      CDC_DepInEmpty = 0;
          USB_WriteEP (CDC_DEP_IN, (unsigned char *)&serBuf[0], numBytesRead);
    }
  }

}

__task void vcomdemo (void) {

  VCOM_Init();                              /* VCOM Initialization */

  USB_Init();                               /* USB Initialization */
  USB_Connect(__TRUE);                      /* USB Connect */

  while (!USB_Configuration) ;              /* wait until USB is configured */

  while (1) {                               /* Loop forever */
    VCOM_Serial2Usb();                      /* read serial port and initiate USB event */
    VCOM_CheckSerialState();
        VCOM_Usb2Serial();
  }
}

Tsuneo