WHAT

DEF

device controller가 CPU를 거치지 않고 memory에 직접 read/write

HOW

[READ]

ALG.

• SETUP-DMA(

  • device = IO device,
  • memory_address = buffer,
  • count = N bytes,
  • direction = DEVICE_TO_MEMORY

• )

• ISSUE-DMA-READ-COMMAND()

• CPU_DO_OTHER_WORK()

• // DMA 완료 interrupt 발생 시

• DMA-INTERRUPT-HANDLER:

  • status := READ-DMA-STATUS()
  • IF (status == ERROR)
    • RETURN error condition
  • done := true