Z86L81 Datasheet, PDF (32/88 Pages) Maxim Integrated Products – 28-Pin Low-Voltage Infrared Microcontrollers

Z86L81/86/98
28-Pin Low-Voltage Infrared Microcontrollers
26
LD RP, #0Dh
; Select ERF D for access to bank D
(working register group 0)
LD RP, #7Dh
; Select expanded register bank D and working
register group 7 of bank 0 for access.
LD 71h, 2
; CTRL2register 71h
LD R1, 2
; CTRL2register 71h
Register File
The register file (bank 0) consists of 4 I/O port registers, 237 general-purpose reg-
isters, and 16 control and status registers (R0–R3, R4–R239, and R240–R255,
respectively). Additionally, there are two expanded registers groups in Banks D
(see Table 9) and F. Instructions can access registers directly or indirectly through
an 8-bit address field, thereby allowing a short, 4-bit register address to use the
Register Pointer (Figure 13). In the 4-bit mode, the register file is divided into 16
working register groups, each occupying 16 continuous locations. The Register
Pointer addresses the starting location of the active working register group.
Counter/Timer Register Description
Table 9. Expanded Register Group D
(D)0Ch
(D)0Bh
(D)0Ah
(D)09h
(D)08h
(D)07h
(D)06h
(D)05h
(D)04h
(D)03h
(D)02h
(D)01h
(D)00h
LVD
HI8
LO8
HI16
LO16
TC16H
TC16L
TC8H
TC8L
Reserved
CTR2
CTR1
CTR0
19-4615; Rev 0; 4/09