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FUJITSU MB91460 SERIES FR60 User Manual

Page 394

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378

Chapter 26 DMA Controller

5.Data Bus

Figure 5-2 Examples of Fly-By Transfer

memory

Memory read by RD or CSn

I/O write by RD or DACK

memory

Memory write by WR or CSn

I/O read by WR or DACK

D-bus

X-bus

I-bus

F-bus

Bus controller

DMAC

RAM

CPU

MB91460

I/O

I/O

I/O

D-bus

X-bus

I-bus

F-bus

Bus controller

DMAC

RAM

CPU

MB91460

I/O

Read cycle

Read cycle

Fly-by transfer (memory to I/O)

Fly-by transfer (I/O to memory)

External bus I/F

Data buffer

Data buffer