Z86E3016PSG Datasheet, PDF (205/348 Pages) Zilog, Inc. – Z86E3016PSG

Z8 CPU
User Manual
187
External Interface
Introduction
The Z8^® CPU can be a microcontroller with 20 pins for external memory
interfacing. The external memory interface on the Z8^® CPU is generally
for either RAM or ROM; this features is only available for devices featur-
ing Port 0, Port 1, R/W, DM, AS, and DS. Please refer to specific product
specifications for availability of these features.
The Z8^® CPU offers a multiplexed external memory interface. In multi-
plexed mode, eight pins from Port 1 form an Address/Data Bus (AD7–
AD0), eight pins from Port 0 form a High Address Bus (A15–A8). Three
additional pins provide the Address Strobe, Data Strobe, and the Read/
Write Signal. Figure 122 shows the Z8^® CPU external interface pins.
(Port 1) AD7–AD0
(Port 0) AD15–AD8
Z8 CPU
AS
DS
R/W
DM
External
Program/Data
64 KB
Each
Figure 122. Z8^® CPU External Interface Pins
UM001602-0904
External Interface