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Free RTOS + USART_TX DMA stm32f2xx

Posted by dfyz on November 6, 2012
I want to use Free RTOS with DMA. Do anybody tries to do this?
My DMA(without RTOS) and USART(with RTOS) are working fine. I have a quastion how i must use DMA with quene.

Now i sent data to tx_quene, and then enable bit in USART Register, which causes interrupt - then i get the data from quene and send their to usart

void USART1_IRQHandler(void)
long higherPriorityTaskWoken = pdFALSE;
unsigned char byte;
if((USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)||(USART1->SR & 0x08)){//theis something in receive buffer or overflow error
byte = USART_ReceiveData(USART1);
xQueueSendFromISR(rxQueue, &byte, &higherPriorityTaskWoken);

if(USART_GetITStatus(USART1, USART_IT_TXE) != RESET){ //TX buffer is clean
if (xQueueReceiveFromISR(txQueue, &byte, &higherPriorityTaskWoken) == pdTRUE) //queue has data
USART_SendData(USART1, byte);
else USART_ITConfig(USART1, USART_IT_TXE, DISABLE); //there is no data left in queue


RE: Free RTOS + USART_TX DMA stm32f2xx

Posted by dfyz on November 19, 2012
It's work! I simply did DMA Transmittion(without RTOS) and USART receiving with RTOS. And all is working now

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