Bit Working Register Addressing Example - Samsung S3F80JB User Manual

S3F80JB
0 1 1 1 0
0 1 1 1 0
Selects
RP0 or RP1
Address
Register pointer
provides five
high-order bits
Together they create an
8-bit register address
Figure 2-12. 4-Bit Working Register Addressing
RP0
0 0 0
Register
1 1 0
address
(76H)
Figure 2-13. 4-Bit Working Register Addressing Example
OPCODE
4-bit address
procides three
low-order bits
RP1
0 1 1 1 1
Selects RP0
R6
0 1 1 0
RP0
RP1
0 0 0
OPCODE
Instruction:
1 1 1 0
'INC R6'
ADDRESS SPACES
2-17