DMA and two or more U(S)ARTs

[pawwodko]

Posted on October 03, 2013 at 09:50

Can I configure two usart's to use one DMA? In datasheet there is table called ''DMAx request mapping'' and for stm32f40/1/2/3 eg. UART4 uses

channel 4 for RX and TX DMA trigger on stream 2 and 4. Can I configure stream 0 and 5 to use UART5 (also chanell 4) at the same time or this setting will collide with settings of UART4 DMA ? #stm32-usart-dma

[waclawek.jan]

Posted on October 03, 2013 at 10:26

Look at the DMA module as 8 independent DMA controllers, one per stream.

JW

[pawwodko]

Posted on October 04, 2013 at 08:18

Triggering channels are also totally independent?

[Tesla DeLorean]

Posted on October 04, 2013 at 11:44

Each stream can be trigger by a single channel (8-to-1 mux)

The stream is the active DMA transaction, the channel is the source of the request.