Make USART writes non-blocking

The application should be the one to decide if a write should be blocking or not
This commit is contained in:
Steins7 2023-09-16 23:50:13 +02:00
parent 7a660c29d2
commit 256e3f30ab
2 changed files with 12 additions and 9 deletions

View File

@ -49,10 +49,11 @@ uint32_t dma_mbuf_write_byte(volatile struct DmaMultiBuffer* buffer,
//if the current buffer is full, we need to switch it with an empty one
if (buffer->byte_index >= buffer->buffer_size) {
//if all buffer full, simply wait for the DMA to empty one
dma_exit_critical(buffer->dma, buffer->channel);
while (buffer->free_buffer_nb == 0) {}
dma_enter_critical(buffer->dma, buffer->channel);
//if all buffer full, give up
if (buffer->free_buffer_nb == 0) {
dma_exit_critical(buffer->dma, buffer->channel);
return 1;
}
++buffer->buffer_index;
if (buffer->buffer_index >= buffer->buffer_nb) {
@ -61,8 +62,6 @@ uint32_t dma_mbuf_write_byte(volatile struct DmaMultiBuffer* buffer,
--buffer->free_buffer_nb;
buffer->byte_index = 0;
} else {
dma_enter_critical(buffer->dma, buffer->channel);
}
//write the byte

View File

@ -134,9 +134,13 @@ uint32_t usart_write_byte(enum UsartPeriph periph, uint8_t byte)
return dma_mbuf_write_byte(buffer, byte);
}
} else {
while (regs->SR.TXE == 0) {}
reg_write(regs->DR, USART_DR_DR, byte);
return 0;
//only write data if the tx register it empty, give up otherwise
if (regs->SR.TXE) {
reg_write(regs->DR, USART_DR_DR, byte);
return 0;
} else {
return 1;
}
}
}