39.6.2.4 DMA Dynamic Linking of a New Transfer Descriptor

  1. Write the new descriptor structure in the system memory.
  2. Write the address of the new structure in the CHXHEAD register.
  3. Add the new structure to the queue of descriptors by writing one to the A2QEN field of the CHXCHER register.
  4. The new descriptor is added to the queue on the next frame.
  5. An interrupt is raised if unmasked, when the head descriptor structure has been loaded by the DMA channel.