Fujitsu CM71-00101-5E User Manual

Fujitsu

82

CHAPTER 7 DETAILED EXECUTION INSTRUCTIONS

7.11

CMP (Compare Word Data in Source Register and
Destination Register)

Subtracts the word data in "Rj" from the word data in "Ri", places results in the
condition code register (CCR).

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CMP (Compare Word Data in Source Register and Destination Register)

Assembler format:

CMP Rj, Ri

Operation:

Ri – Rj

Flag change:

N : Set when the MSB of the operation result is "1", cleared when the MSB is "0".

Z : Set when the operation result is "0", cleared otherwise.

V : Set when an overflow has occurred as a result of the operation, cleared otherwise.

C : Set when a borrow has occurred as a result of the operation, cleared otherwise.

Execution cycles:

1 cycle

Instruction format:

Example:

CMP R2, R3

N

Z

V

C

C

C

C

C

MSB

LSB

1

0

1

0

1

0

1

0

Rj

Ri

R2

R3

1 2 3 4

5 6 7 8

1 2 3 4

5 6 7 8

N Z V C

CCR

R2

R3

CCR

0 0 0 0

N Z V C

0 1 0 0

1 2 3 4

5 6 7 8

1 2 3 4

5 6 7 8

Before execution

After execution

Instruction bit pattern : 1010 1010 0010 0011