Posted on April 10, 2013 at 09:55I use stm32f207 USB device examples VCP deom .I change the USB CDC device Configuration Descriptor like this
/*Configuration Descriptor*/
0x09, /* bLength: Configuration Descriptor size */
USB_CONFIGURATION_DESCRIPTOR_TYPE, /* bDescriptorType: Configuration */
USB_CDC_CONFIG_DESC_SIZ, /* wTotalLength:no of returned bytes */
0x00,
0x01, /* bNumInterfaces: 1 interface */
0x01, /* bConfigurationValue: Configuration value */
0x00, /* iConfiguration: Index of string descriptor describing the configuration */
0xC0, /* bmAttributes: self powered */
250, /* MaxPower 2 mA */
/*Data class interface descriptor*/
0x09, /* bLength: Endpoint Descriptor size */
USB_INTERFACE_DESCRIPTOR_TYPE, /* bDescriptorType: */
0x00, /* bInterfaceNumber: Number of Interface */
0x00, /* bAlternateSetting: Alternate setting */
0x02, /* bNumEndpoints: Two endpoints used */
0xff, /* bInterfaceClass: USER */
0x00, /* bInterfaceSubClass: */
0x00, /* bInterfaceProtocol: */
0x00, /* iInterface: */
//18
/*Endpoint OUT Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
0x03, /* bEndpointAddress */
0x02, /* bmAttributes: Bulk */
0x40, /* wMaxPacketSize: */
0,
0, /* bInterval: ignore for Bulk transfer */
//25
/*Endpoint IN Descriptor*/
0x07, /* bLength: Endpoint Descriptor size */
USB_ENDPOINT_DESCRIPTOR_TYPE, /* bDescriptorType: Endpoint */
0x82, /* bEndpointAddress */
0x02, /* bmAttributes: Bulk */
0x40, /* wMaxPacketSize: */
0,
0 /* bInterval: ignore for Bulk transfer */
//32
and I send function :
uint16_t VCP_DataTx (uint8_t* Buf, uint32_t Len)
{
uint8_t i;
for (i=0;i<64;i++) //this number must be
multiple
of 64 ,anyother number wil not be send out.
{
APP_Rx_Buffer[APP_Rx_ptr_in] = g_ucaHeartbeat;
APP_Rx_ptr_in++;
/* To avoid buffer overflow */
if(APP_Rx_ptr_in == APP_RX_DATA_SIZE)
{
APP_Rx_ptr_in = 0;
}
}
return USBD_OK;
}
#stm32f207-cdc-virtualcom-usb
