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                                                         To
                      DMA CONTROLLER WRITES   BLOCK OF   INTERRUPT  cpu
 m                    DATATO SUCCESSIVE
 4
                      LOCATIONS IN MEMORY
 INCOMING SERIAL DATA   ............

             CONTROLLER
                        DMA CONTROLLER READS
                        DATA FROM SUCCESSIM       RY
             ............
 OUTGOING SERIAL DATA













 DMA TRANSFER FROM UART  DMA REQUEST
 FROM UART   I
 HOLD



 Bus   cpu   DMA CONTROLLER   DMA CONTROLLER   cW
 (READING MEMORY)   (WRITING UART)
 3   OMA TRANSFER TO UART
 B

 %   HLDA


 Figure 2.24
 DMA Transfer Example.
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