Samsung KS57C2308 manual Cpse Compare and Skip if Equal, Cpse EA,HL RET

KS57C2308/P2308/C2316/P2316SAM47 INSTRUCTION SET

CPSE — Compare and Skip if Equal

CPSE	dst,src
Operation:	Operand	Operation Summary	Bytes	Cycles
	R,#im	Compare and skip if register equals #im	2	2 + S
	@HL,#im	Compare and skip if indirect data memory equals #im	2	2 + S
	A,R	Compare and skip if A equals R	2	2 + S
	A,@HL	Compare and skip if A equals indirect data memory	1	1 + S
	EA,@HL	Compare and skip if EA equals indirect data memory	2	2 + S
	EA,RR	Compare and skip if EA equals RR	2	2 + S

Description: CPSE compares the source operand (subtracts it from) the destination operand, and skips the next instruction if the values are equal. Neither operand is affected by the comparison.

Operand				Binary Code						Operation Notation
R,#im	1	1	0		1	1	0	0	1	Skip if R = im
	d3	d2	d1		d0	0	r2	r1	r0
@HL,#im	1	1	0		1	1	1	0	1	Skip if (HL) = im
	0	1	1		1	d3	d2	d1	d0
A,R	1	1	0		1	1	1	0	1	Skip if A = R
	0	1	1		0	1	r2	r1	r0
A,@HL	0	0	1		1	1	0	0	0	Skip if A = (HL)
EA,@HL	1	1	0		1	1	1	0	0	Skip if A = (HL), E = (HL+1)
	0	0	0		0	1	0	0	1
EA,RR	1	1	0		1	1	1	0	0	Skip if EA = RR
	1	1	1		0	1	r2	r1	0

Example: The extended accumulator contains the value 34H and register pair HL contains 56H. The second instruction (RET) in the instruction sequence

CPSE EA,HL

RET

is not skipped. That is, the subroutine returns since the result of the comparison is “not equal”.

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