Fujitsu FR60 用户手册

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Chapter 26  DMA Controller

4.Operation Flowcharts

■

Load the initial address,

transfer count, and

number of blocks

Activation request

wait

DMA transfer end

DMA interrupted

BLK=0

DTC=0

DMA stop

DENB=1

DENB=>0

Write back the address,

transfer count, and number

of blocks

Number of blocks - 1

Interrupt clear

One-time access for fly-by

Reload enable

Only when the peripheral interrupt
activation source is selected

Calculate the address for

transfer source address access

Calculate the address for transfer

destination address access

Transfer count - 1

Interrupt cleared

Burst transfer
-  Can be activated by all activation sources (selection).
-  Can access to all areas.
-  The number of blocks can be set.
-  Interrupt clear and the DMA interrupt are issued when 

   transfer for the number of times specified is completed.