Hello,
I have an application where I transfer data to and from a PC with a FT232R and a UART. There is data beeing transfered back and foth constantly and asynchrone to another, so it is sending and receiveing at any random time and simultaneously. Sending and receiving is done by interrupt and use the same interrupt (checking in the interrupt which flag is active). I noticed that there was something wrong and toggled a pin each time the UART reived a byte. The problem is that it occaseonly misses some single bytes. This is when there are several hundred bytes transmitted to the STM32 at the maximum rate without delay between the bytes. Generally the UART is supposed to be fullduplex. The interrupt routine is shorter than a byte. So maybe the sending and receiving on the same interrupt is causing this.
I wondered now if it is possible to send the bytes not by interrupt but by using a DMA with a DMA finished interrupt while receiving the bytes with the UART interrupt? It seems strange as the USRT interrupt is the second highes priority with the highes only active for very short times (much less than one byte length). So it should fire after the other one is done. But the byte is missed completely.
So how is the "normal" way to acheive sending and receiving at high rates over the full duplex UART (I got FIFOs for both directions)? I thought it was quite straight forward.
Edit: Is it possible to use two DMA for transmitting and receiving at the same time on the UART?
