DESCRIPTION OF INSTRUCTIONS

103. XCH A, Rr (Exchange register with accumulator)

 

 

 

7

 

 

 

 

 

 

0

 

Instruction code

:

 

1

1

0

0

1

r2

r1

r0

Byte 1

Operation

 

 

 

 

 

 

 

 

 

 

: (A)(Rr) r=0 thru 7

 

 

 

 

 

Number of bytes

: 1

 

 

 

 

 

 

 

 

 

Number of cycles

: 1

 

 

 

 

 

 

 

 

 

Flags

:

 

C

AC

F0

RS1

RS0

OV

F1

P

(PSW)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Description

 

 

 

 

 

 

 

 

 

 

: The accumulator contents are exchanged with the register r

 

 

contents, and the flag is updated.

 

 

 

Example XCH A, R5

 

 

 

 

 

 

 

 

 

 

 

 

7

 

 

 

0

 

 

 

 

 

Instruction code

:

1

1

0 0

1 1

0 1

Byte 1

 

 

 

Before execution Accumulator

0 1 1 1 0 0 1 0

70 Register 5

1 0 1 0 0 0 0 1

70

After execution Accumulator

1 0 1 0 0 0 0 1

70 Register 5

0 1 1 1 0 0 1 0

70

363

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Sonic Alert msm80154s, msm83c154s, msm85c154hvs user manual XCH A, Rr Exchange register with accumulator, 363