SAM47 INSTRUCTION SET KS57C2308/P2308/C2316/P2316
5-76
REF — Reference Instruction
REF (Continued)
Examples: 1. Instructions can be executed efficiently using REF, as shown in the following example:
ORG 0020H
AAA LD HL,#00H
BBB LD EA,#FFH
CCC TCALL SUB1
DDD TJP SUB2
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ORG 0080H
REF AAA ; LD HL,#00H
REF BBB ; LD EA,#FFH
REF CCC ; CALL SUB1
REF DDD ; JP SUB2
2. The following example shows how the REF instruction is executed in relation to LD
instructions that have a “redundancy effect”:
ORG 0020H
AAA LD EA,#40H
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ORG 0100H
LD EA,#30H
REF AAA ; Not skipped
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REF AAA
LD EA,#50H ; Skipped
SRB 2