Intel UPI- 41A, Руководство пользователя

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UPI-41A/41AH/42/42AH USER’S MANUAL
SWAP A Swap Nibbles Within Accumulator
Opcode: 0 1 0 0 0 1 1 1
Bits 0 – 3 of the accumulator are swapped with bits 4-7 of the accumulator.
(A
4–7
)
Ý
(A
0–3
)
Example:
Pack bits 0 – 3 of locations 50-51 into location 50.
PCKDIG: MOV R0,
Ý 50 ;MOVE ‘50’ DEC TO REG 0
MOV R1, Ý 51 ;MOVE ‘51’ DEC TO REG 1
XCHD A, @ R0 ;EXCHANGE BIT 0 – 3 OF ACC
;AND LOCATION 50
SWAP A ;SWAP BITS 0 – 3 AND 4 – 7 OF ACC
XCHD A, @ R1 ;EXCHANGE BITS 0 – 3 OF ACC AND
;LOCATION 51
MOV @ R0,A ;MOVE CONTENTS OF ACC TO
;LOCATION 51
XCH ARr Exchange Accumulator-Register Contents
Opcode: 0 0 1 0 1 r
2
r
1
r
0
The contents of the accumulator and the contents of working register ‘r’ are exchanged.
(A)
Ý
(Rr) r
e
0 – 7
Example: Move PSW contents to Reg 7 without losing accumulator contents.
XCHAR7: XCH A,R7
;EXCHANGE CONTENTS OF REG 7
;AND ACC
MOV A,PSW ;MOVE PSW CONTENTS TO ACC
XCH, A,R7 ;EXCHANGE CONTENTS OF REG 7
;AND ACC AGAIN
XCH A, @ Rr Exchange Accumulator and Data Memory Contents
Opcode: 0 0 1 0 0 0 0 r
The contents of the accumulator and the contents of the data memory location addressed by
bits 0 – 7 of register ‘r’ are exchanged. Register ‘r’ contents are unaffected.
(A)
Ý
((Rr)) r
e
0 – 1
Example: Decrement contents of location 52.
DEC 52: MOV R0,
Ý 52 ;MOVE ‘52’ DEC TO ADDRESS
;REG 0
XCH A, @ R0 ;EXCHANGE CONTENTS OF ACC
;AND LOCATION 52
DEC A ;DECREMENT ACC CONTENTS
XCH A, @ R0 ;EXCHANGE CONTENTS OF ACC
;AND LOCATION 52 AGAIN
51