z80189 ZiLOG Semiconductor, z80189 Datasheet - Page 214

• Manufacturer Part Number: z80189
• Description: Z80180, Z8s180, Z8l180 Mpu Operation
• Manufacturer: ZiLOG Semiconductor

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UM005003-0703
Z8018x
Family MPU User Manual
A19–0, D7–0
MREQ, RD
WR, IORQ
INT0,1,2
BUSREQ
Data IN
BUSACK
MREQ
RFSH
IORQ
PHI
HALT
NMI
M1
Memory Read/Write Cycle timing is the sam as I/O Read/Write Cycle
except there are no automatica Wait States (TW), and MREQ is active
instead of IORQ.
Figure 82.
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AC Timing Diagram 2
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10
Output Buffer Off
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