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Figure 4-2 – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 26 DMA Controller

4.Operation Flowcharts

Figure 4-2 Operation Flowchart for Burst Transfer

Demand Transfer

Figure 4-3

"Operation Flowchart for Demand Transfer" shows the operation flowchart for demand transfer.

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.