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Chapter 31 External Bus
10.DMA Access Operation
10. DMA Access Operation
This section explains DMA access operation.
■ DMA Access Operation
This section explains the following five DMA operations:
• DMA fly-by transfer (I/O -> memory)
• DMA fly-by transfer (memory -> I/O)
• 2-cycle transfer (internal RAM -> I/O, RAM)
• 2-cycle transfer (external -> I/O)
• 2-cycle transfer (I/O -> external)
10.1 DMA Fly-By Transfer (I/O -> Memory)
This section explains DMA fly-by transfer (I/O -> memory).
■ DMA Fly-By Transfer (I/O -> Memory)
Figure 10-1 "Timing Chart for DMA Fly-By Transfer (I/O -> Memory)" shows the operation timing chart for (TYP3-
0=0000
B
, AWR=0008
H
, IOWR=41
H
).
Figure 10-1 "Timing Chart for DMA Fly-By Transfer (I/O -> Memory)" shows when case when a wait is not set on
the memory side.