dmasim800

STM32 , main loop does fire if receive data quickly using DMA


I am using DMA in circular mode with STM32 sim800c module. i can send/receive AT commands/response without any issue, but getting issue when i tried to download file using AT command, when start receiving data from UART, DMA RxCpltCallback function getting call very quickly and main loop does not getting fired until all data received. once all data received then loop function get fired and then i check response which contain last chunk of file (64 bytes).

how can i handle this situation?


Solution

  • Increase the size of the DMA buffer. The interrupt will be invoked less frequently. IF your UART speed is really high (about 10Mb) use flow control (CTS/RTS) to control the communication.l