13.4.11.3 Ping-Pong Transmit Initialization

The following description serves only as a guideline for the firmware implementation.

Transmit data as an initiator:

  1. User’s SW sets up peripheral for transmit.
  2. User’s SW sets up DMA Channel 0 and Channel 1.
  3. User’s SW writes Buffer 1.
  4. User’s SW enables DMA Channel 0.
  5. User’s SW enables peripheral which later triggers for transmit data.
  6. DMA Channel 0 reads from Buffer 1 while user’s SW writes to Buffer 2.
  7. See the steady-state description in Ping-Pong Transmit Steady State.

Transmit data as a responder:

  1. User’s SW sets up DMA Channel 0 and Channel 1, part of a boot-up or initialization routine.
  2. User’s SW sets up peripheral for transmit, part of a boot-up or initialization routine.
  3. User’s SW writes Buffer 1, part of a boot-up or initialization routine.
  4. User’s SW gets INT when peripheral triggers DMA for transmit data (in response to the host requesting data).
  5. DMA Channel 0 reads from Buffer 1 while user’s SW writes to Buffer 2.
  6. See the steady-state description in Ping-Pong Transmit Steady State.