Z80 Datasheet, PDF (65/330 Pages) Zilog, Inc. – Z80 CPU PERIPHERALS

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Sequential
Transfer
(Flow through)
CPU
Simultaneous
Transfer
(Flyby)
CPU
Search
Only
Read
Write
MEMORY
DMA
I/O
Read/Write
MEMORY
DMA
I/O
Read
CPU
Sequential
ransfer/Search
MEMORY
DMA
I/O
Read
Write
CPU
Simultaneous
ransfer/Search
MEMORY
DMA
I/O
Read
Write
CPU
MEMORY
DMA
Figure 18. Class of Operation
80
I/O
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