9.2. DMA Circularly Receives Uart Data

9.2.1. Overview

  • This example project shows the DMA circularly transfer mode realized by chain transfer.

  • The ChnLLPointer of the two chain descriptors point to each other, A point to B, and B point to A. After A transfer completed, B will be transferred, and after B transfer completed, A will be transferred, thus realizing circularly transfer without software intervention.

9.2.2. Board Setting

  • Use the serial port debugging assistant to send and receive data

  • The serial port is set to 115200bps , 1 stop bit , no parity bit

9.2.3. Running the example

  • Use the serial port debugging assistant to send data, and the development board will send back the received data, as shown in the following example

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