Z86E30 Datasheet, PDF (35/66 Pages) Zilog, Inc. – Z8 4K OTP Microcontroller

Zilog
Z86E30/E31/E40
Z8 4K OTP Microcontroller
1
r7 r6 r5 r4
r3 r2 r1 r0
R253
(Register Pointer)
The upper nibble of the register file address
provided by the register pointer specifies
the active working-register group.
FF
Register Group F
F0
EF
80
7F
Note: Registers 80H
through EFH are
available in the Z86C30
only.
70
6F
60
5F
50
4F
40
3F
Specified Working
Register Group
30
2F
20
1F
Register Group 1
10
0F
Register Group 0
The lower nibble
of the register
file address
provided by the
instruction points
to the specified
register.
R15 to R0
R15 to R4*
00
I/O Ports
* Expanded Register Group (0) is selected
in this figure by handling bits D3 to D0 as
"0" in Register R253 (RP).
R3 to R0*
Figure 25. Register Pointer
DS97Z8X0500
PRELIMINARY
35