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stmhal: Improve USB CDC write function (increase timeout).

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This commit is contained in:
Damien George 2014-04-13 16:39:04 +01:00
parent 0e4ba25834
commit 212f89e61a
1 changed files with 4 additions and 6 deletions
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10
stmhal/usbd_cdc_interface.c
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@ -362,12 +362,10 @@ void USBD_CDC_SetInterrupt(int chr, void *data) {
void USBD_CDC_Tx(const char *str, uint32_t len) {
for (int i = 0; i < len; i++) {
uint timeout = 200;
while (((UserTxBufPtrIn + 1) & (APP_TX_DATA_SIZE - 1)) == UserTxBufPtrOut) {
if (timeout-- == 0) {
break;
}
HAL_Delay(1);
// if the buffer is full, wait until it gets drained, with a timeout of 1000ms (wraparound of tick is taken care of by 2's complement arithmetic)
uint32_t start = HAL_GetTick();
while (((UserTxBufPtrIn + 1) & (APP_TX_DATA_SIZE - 1)) == UserTxBufPtrOut && HAL_GetTick() - start <= 1000) {
__WFI(); // enter sleep mode, waiting for interrupt
}
UserTxBuffer[UserTxBufPtrIn] = str[i];
UserTxBufPtrIn = (UserTxBufPtrIn + 1) & (APP_TX_DATA_SIZE - 1);