8.2. DMA Circularly Receives Uart Data

8.2.1. 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 transfered, and after B transfer completed, A will be transfered, thus realizing circularly transfer without software intervention.

8.2.2. 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

8.2.3. 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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