diff options
| -rw-r--r-- | stmhal/usbd_cdc_interface.c | 53 |
1 files changed, 35 insertions, 18 deletions
diff --git a/stmhal/usbd_cdc_interface.c b/stmhal/usbd_cdc_interface.c index 8a2470c853..a62f8a801f 100644 --- a/stmhal/usbd_cdc_interface.c +++ b/stmhal/usbd_cdc_interface.c @@ -46,7 +46,7 @@ /* Private typedef -----------------------------------------------------------*/ /* Private define ------------------------------------------------------------*/ -#define APP_RX_DATA_SIZE 1024 // I think this must be at least CDC_DATA_FS_OUT_PACKET_SIZE (was 2048) +#define APP_RX_DATA_SIZE 1024 // I think this must be at least CDC_DATA_FS_OUT_PACKET_SIZE=64 (APP_RX_DATA_SIZE was 2048) #define APP_TX_DATA_SIZE 1024 // I think this can be any value (was 2048) /* Private macro -------------------------------------------------------------*/ @@ -138,8 +138,13 @@ static int8_t CDC_Itf_Init(void) UserRxBufCur = 0; UserRxBufLen = 0; + /* NOTE: we cannot reset these here, because USBD_CDC_SetInterrupt + * may be called before this init function to set these values. + * This can happen if the USB enumeration occurs after the call to + * USBD_CDC_SetInterrupt. user_interrupt_char = VCP_CHAR_NONE; user_interrupt_data = NULL; + */ return (USBD_OK); } @@ -252,7 +257,7 @@ void USBD_CDC_HAL_TIM_PeriodElapsedCallback(void) { { if(UserTxBufPtrOut > UserTxBufPtrIn) /* rollback */ { - buffsize = APP_RX_DATA_SIZE - UserTxBufPtrOut; + buffsize = APP_TX_DATA_SIZE - UserTxBufPtrOut; } else { @@ -266,7 +271,7 @@ void USBD_CDC_HAL_TIM_PeriodElapsedCallback(void) { if(USBD_CDC_TransmitPacket(&hUSBDDevice) == USBD_OK) { UserTxBufPtrOut += buffsize; - if (UserTxBufPtrOut == APP_RX_DATA_SIZE) + if (UserTxBufPtrOut == APP_TX_DATA_SIZE) { UserTxBufPtrOut = 0; } @@ -289,9 +294,20 @@ static int8_t CDC_Itf_Receive(uint8_t* Buf, uint32_t *Len) { HAL_UART_Transmit_DMA(&UartHandle, Buf, *Len); #endif + // TODO improve this function to implement a circular buffer + + // if we have processed all the characters, reset the buffer counters + if (UserRxBufCur > 0 && UserRxBufCur >= UserRxBufLen) { + memmove(UserRxBuffer, UserRxBuffer + UserRxBufLen, *Len); + UserRxBufCur = 0; + UserRxBufLen = 0; + } + + uint32_t delta_len; + if (user_interrupt_char == VCP_CHAR_NONE) { // no special interrupt character - UserRxBufLen = *Len; + delta_len = *Len; } else { // filter out sepcial interrupt character from the buffer @@ -310,25 +326,29 @@ static int8_t CDC_Itf_Receive(uint8_t* Buf, uint32_t *Len) { } } - // set length of remaining characters - UserRxBufLen = dest - Buf; - if (char_found) { // raise exception when interrupts are finished user_interrupt_char = VCP_CHAR_NONE; pendsv_nlr_jump(user_interrupt_data); } - } - // there are new characters at the start of the buffer, so point there - UserRxBufCur = 0; + // length of remaining characters + delta_len = dest - Buf; + } - if (UserRxBufLen == 0) { - // initiate next USB packet transfer now that UserRxBuffer has been drained - USBD_CDC_ReceivePacket(&hUSBDDevice); + if (UserRxBufLen + delta_len + CDC_DATA_FS_MAX_PACKET_SIZE > APP_RX_DATA_SIZE) { + // if we keep this data then the buffer can overflow on the next USB rx + // so we don't increment the length, and throw this data away + } else { + // data fits, leaving room for another CDC_DATA_FS_OUT_PACKET_SIZE + UserRxBufLen += delta_len; } - return (USBD_OK); + // initiate next USB packet transfer, to append to existing data in buffer + USBD_CDC_SetRxBuffer(&hUSBDDevice, UserRxBuffer + UserRxBufLen); + USBD_CDC_ReceivePacket(&hUSBDDevice); + + return USBD_OK; } int USBD_CDC_IsConnected(void) { @@ -366,9 +386,6 @@ int USBD_CDC_RxGet(void) { // get next character int c = UserRxBuffer[UserRxBufCur++]; - if (UserRxBufCur >= UserRxBufLen) { - // initiate next USB packet transfer now that UserRxBuffer has been drained - USBD_CDC_ReceivePacket(&hUSBDDevice); - } + return c; } |