Samsung KS57C2308 manual Jr Kk, Jps Aaa Bbb Ccc Ddd, Ea,Wx Ads Wx,Ea, Jps Yyy Xxx Ld

KS57C2308/P2308/C2316/P2316 SAM47 INSTRUCTION SET

JR — Jump Relative (Very Short)

JR(Continued)

Examples: 1. A short form for a relative jump to label “KK” is the instruction

JR KK

where “KK” must be within the allowed range of current PC–15 to current PC+16. The JR instruction has in this case the effect of an unconditional JP instruction.

2.In the following instruction sequence, if the instruction “LD WX, #02H” were to be executed in place of “LD WX,#00H”, the program would jump to 1004H andJPS“ CCC” would be executed. If “LD EA,#03H” were to be executed, the jump would be to1006H andJPS“ DDD” would be executed.

ORG	1000H
JPS	AAA
JPS	BBB
JPS	CCC
JPS	DDD
LD	WX,#00H	; WX ← 00H
LD	EA,WX
ADS	WX,EA	; WX ← (WX) + (WX)
JR	@WX	; Current PC13–8 (10H) + WX (00H) = 1000H
		; Jump to address 1000H and execute JPS AAA
3. Here is another example:
ORG	1100H
LD	A,#0H
LD	A,#1H
LD	A,#2H
LD	A,#3H
LD	30H,A	; Address 30H ← A
JPS	YYY
XXX LD	EA,#00H	; EA ← 00H
JR	@EA	; Jump to address 1100H
		; Address 30H ← 00H

If “LD EA,#01H” were to be executed in place of “LD EA,#00H”, the program would jump to 1001H and address 30H would contain the value 1H. If “LD EA,#02H” were to be executed, the jump would be to 1002H and address 30H would contain the value 2H.

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