DMA UART

[manoritesameer]

Posted on July 29, 2014 at 20:26

I am trying to send an array over UART using the DMA. I dont know why the DMA does not send more than 65535 elements.

Is there a restriction on the DMA for only 16Bit numbers only ? #stm32f4 #board #discovery #rtfm #adc

[Tesla DeLorean]

Posted on July 29, 2014 at 21:15

[manoritesameer]

Posted on July 29, 2014 at 22:11Thanks Clive again :), Is there a way to transfer more that 65535 values using DMA UART at once. 

[Tesla DeLorean]

Posted on July 29, 2014 at 22:28

Well you can make it send data continuously by being in circular mode. You can copy to ping/pong buffers at HT/TC interrupts. Ideally you don't want to be copying data.

You can use DMA to handle 16 or 32-bit words, but this doesn't help with the USART. The most practical solution is to simply chain DMA requests, or scatter-gather, at the TC interrupt, and light off a new request. Sending multiple strings via USART at the end of

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