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6.5. DMA Transfer Mode
6.5.1. Basic Transfer
This is the basic DMA transfer mode. In this mode, DMA transfer starts when a DMA transfer
request from a peripheral circuit or a software DMA request is issued, and it continues until it is
completed for the set number of successive transfers or it is suspended at the arbitration cycle. To
resume the DMA transfer suspended at the arbitration cycle, a DMA transfer request must be
reissued.
When the set number of successive transfers has completed, a transfer completion interrupt occurs.
DMA transfer operation
DMACENDIF.ENDIFn
Figure 6.5.1.1 Basic Transfer Operation Example (N = 8, 2
6.5.2. Auto-Request Transfer
Similar to the basic transfer, DMA transfer starts when a DMA transfer request from a peripheral
circuit or a soft- ware DMA request is issued, and it continues until it is completed for the set
number of successive transfers or it is suspended at the arbitration cycle. The DMAC resumes the
DMA transfer suspended at the arbitration cycle with- out a DMA transfer request being reissued.
When the set number of successive transfers has completed, a transfer completion interrupt occurs
DMA transfer operation
DMACENDIF.ENDIFn
Figure 6.5.2.1 Auto-Request Transfer Operation Example (N = 8, 2
6-6
DMA transfer 1 DMA transfer 2
DMA transfer 3 DMA transfer 4
DMA transfer request
DMA transfer request
DMA transfer 1 DMA transfer 2
DMA transfer request
Seiko Epson Corporation
DMA transfer 3 DMA transfer 4
DMA transfer 7 DMA transfer 8
DMA transfer request
= 2)
R
DMA transfer 7 DMA transfer 8
= 2)
R
S1C31D50 TECHNICAL MANUAL
(Rev. 1.00)
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