UART Transfer Complete ISR vs DMA Transfer Complete ISR for putting message to FreeRTOS MessageQueue

[Rroma.1]

Hello everyone,

I would like to ask for some guidance on which Interrupt i should use for FreeRTOS message queue to help synchronize my state machine.

I am using UART to transmit data to device, and i would like to know if i have finished transmitting. Should I use DMA Transfer Complete or UART Transfer Complete?

Thanks!

[Tesla DeLorean · Accepted solution]

TC on the USART indicates all the bits are over the wire, whereas TC on the DMA indicates all memory moved from that buffer into the pending shift register and buffers on the USART side.

TC on DMA will signal prior to data traversing the wire.

[Rroma.1]

Thanks for your swift response!