Z8
®
CPU
User Manual
UM001604-0108
Address Space
5
Address Space
Introduction
Z8
®
CPU includes the following four address spaces:
•
The Z8 Standard Register File contains addresses for peripheral, control, all general-
purpose, and all I/O port registers. This is the default register file specification.
•
The
Z8 Expanded Register File (ERF) contains addresses for control and data regis-
ters for additional peripherals/features.
•
Z8 external Program Memory contains addresses for all memory locations having
executable code and/or data.
•
Z8 external data memory contains addresses for all memory locations that hold data
only, whether internal or external.
Z8
®
CPU Standard Register File
The
Z8 Standard Register File totals up to 256 consecutive bytes (Registers). The register
file consists of 4 I/O ports (
00h–03h
), 236 General-Purpose Registers (
04h–EFh
), and 16
control registers (
F0h–FFh
).
lists the layout of the register file, including register
names, locations, and identifiers.
Table 2. Z8 Standard Register File
Hex Address
Register
Identifier
Register Description
FF
SPL
Stack Pointer Low Byte
FE
SPH
Stack Pointer High Byte
FD
RP
Register Pointer
FC
FLAGS
Program Control Flags
FB
IMR
Interrupt Mask Register
FA
IRQ
Interrupt Request Register
F9
IPR
Interrupt Priority Register
F8
P01M
Port 0–1 Mode Register
F7
P3M
Port 3 Mode Register
F6
P2M
Port 2 Mode Register
F5
PRE0
T0 Prescaler