SAM47 INSTRUCTION SETKS57C2308/P2308/C2316/P2316

INCS — Increment and Skip on Carry

INCS

dst

 

 

 

 

 

 

 

 

Operation:

Operand

Operation Summary

Bytes

Cycles

 

 

 

 

 

 

R

Increment register (R); skip on carry

1

1 + S

 

 

 

 

 

 

DA

Increment direct data memory; skip on carry

2

2 + S

 

 

 

 

 

 

@HL

Increment indirect data memory; skip on carry

2

2 + S

 

 

 

 

 

 

RRb

Increment register pair (RRb); skip on carry

1

1 + S

 

 

 

 

 

Description: The instruction INCS increments the value of the destination operand by one. An original value of 0FH will, for example, overflow to 00H. If a carry occurs, the next instruction is skipped. The carry flag value is unaffected.

Operand

 

 

 

Binary Code

 

 

 

Operation Notation

 

 

 

 

 

 

 

 

 

 

 

 

R

0

1

0

 

1

1

 

r2

r1

r0

R R + 1; skip on carry

 

 

 

 

 

 

 

 

 

 

 

 

DA

1

1

0

 

0

1

 

0

1

0

DA DA + 1; skip on carry

 

 

 

 

 

 

 

 

 

 

 

 

 

a7

a6

a5

 

a4

a3

 

a2

a1

a0

 

 

 

 

 

 

 

 

 

 

 

 

 

@HL

1

1

0

 

1

1

 

1

0

1

(HL) (HL) + 1; skip on carry

 

 

 

 

 

 

 

 

 

 

 

 

 

0

1

1

 

0

0

 

0

1

0

 

 

 

 

 

 

 

 

 

 

 

 

 

RRb

1

0

0

 

0

0

 

r2

r1

0

RRb RRb + 1; skip on carry

 

 

 

 

 

 

 

 

 

 

 

 

Example: Register pair HL contains the value 7EH (01111110B). RAM location 7EH contains 0FH. The instruction sequence

INCS

@HL

;

7EH "0"

INCS

HL

;

Skip

INCS

@HL

;

7EH "1"

leaves the register pair HL with the value 7EH and RAM location 7EH with the value 1H. Since a carry occurred, the second instruction is skipped. The carry flag value remains unchanged.

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Samsung KS57C2308 manual Incs Increment and Skip on Carry, Incs @HL