DMA question

Discussion created by lpcware Employee on Jun 15, 2016
Content originally posted in LPCWare by schisanoa on Wed Oct 01 07:15:10 MST 2014

I would understand what is the best way to use DMA for the UART RX. I need to receive data at high data rate, about 921600 or more, and I would use the DMA to optimize the firmware, but I don't have a fixed lenght for data, so if I set a transfer for each single byte I suppose it will be not useful, and not optimized, but if I set a transfer size for the DMA of 256 byte, if I receive less than 256 byte, the DMA interrupt won't be asserted. How you may manage this problem? Any suggestion?

I use a FreeRTOS, maybe  using a queue with a timeout?