Z8 Microcontrollers
ZiLOG
Instruction Descriptions and Formats
UM001600-Z8X0599
12-69
SRP
SET REGISTER POINTER
Note:
When an Expanded Register Bank , other than Bank 0 is selected, access to the Z8 Standard Register
File is possible except for the Port Register and general purpose registers 04H to 0FH.
fpr Register Addresses 0H to FH.
Example:
The statement:
SRP F0H Op Code: 31 F0
sets the Register Pointer to access expanded Register Bank 0 and Working Register Group F in the Z8
Standard Register File. All references to Working Registers now affect this group of 16 registers.
Registers F0H to FFH can be accessed as Working Registers R0 to R15
Example:
The statement:
SRP 0FH
Op Code: 31 0F
sets the Register Pointer to access Expanded Register Bank F, Reg 00H to Reg 0FH, as the current
Working Registers. All references to Working Registers now affect this group of 16 registers. These
registers are now accessed as Working Registers R0 to R15. Port Registers are now not accessable.
Register Pointer
(FDH)
Contents (Hex)
xxxx 1111
xxxx 1110
xxxx 1101
xxxx 1100
xxxx 1011
xxxx 1010
xxxx 1001
xxxx 1000
xxxx 0111
xxxx 0110
xxxx 0101
xxxx 0100
xxxx 0011
xxxx 0010
xxxx 0001
xxxx 0000
Expanded
Register Bank
(Hex)
F
E
D
C
B
A
9
8
7
6
5
4
3
2
1
0
Working
Registers
(Dec)
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
R0-R15
Flags:
C:
Z:
S:
V:
D:
H:
Unaffected
Unaffected
Unaffected
Unaffected
Unaffected
Unaffected