Samsung KS57C2308 Manual page 133

KS57C2308/P2308/C2316/P2316
JR
— Jump Relative (Very Short)
JR (Continued)
Examples: 1. A short form for a relative jump to label "KK" is the instruction
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 and "JPS CCC" would be
executed. If "LD EA,#03H" were to be executed, the jump would be to1006H and "JPS DDD"
would be executed.
3. Here is another example:
XXX
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.
JR KK
ORG 1000H
JPS AAA
JPS BBB
JPS CCC
JPS DDD
LD WX,#00H
LD EA,WX
ADS WX,EA
JR @WX
ORG 1100H
LD A,#0H
LD A,#1H
LD A,#2H
LD A,#3H
LD 30H,A
JPS YYY
LD EA,#00H
JR @EA
; WX 00H
; WX (WX) + (WX)
; Current PC13–8 (10H) + WX (00H) = 1000H
; Jump to address 1000H and execute JPS AAA
; Address 30H A
; EA 00H
; Jump to address 1100H
; Address 30H 00H
SAM47 INSTRUCTION SET
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