Samsung S3F80JB manual Bit Working Register Addressing

S3F80JB ADDRESS SPACES

RP0

RP1

Selects

RP0 or RP1

Address OPCODE

Register pointer provides five high-order bits

4-bit address procides three low-order bits

Together they create an

8-bit register address

Figure 2-12. 4-Bit Working Register Addressing

				RP0										RP1
0	1	1	1	0	0	0	0		0	1	1	1	1	0	0	0
									Selects RP0
													R6			OPCODE
								Register
0	1	1	1	0	1	1	0
								address
											0	1	1	0	1		1	1	0
								(76H)

Instruction: 'INC R6'

Figure 2-13. 4-Bit Working Register Addressing Example

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