28 lines
503 B
Text
28 lines
503 B
Text
org 100h ; program load point under CP/M
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;
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; the assembler itself will negate an
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; 8 or 16-bit constant for us
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;
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mvi a,-43 ; a = D5
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lxi h,-43 ; hl = FFD5
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;
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; no built-in opcode to negate an 8-bit
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; register, but nevertheless easily done
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;
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mvi a,43 ; a = 2B
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cma
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inr a ; a = D5
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;
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; the same approach for 16-bit values
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;
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lxi h,43 ; hl = 002B
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mov a,l
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cma
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mov l,a
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mov a,h
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cma
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mov h,a
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inx h ; hl = FFD5
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;
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jmp 0 ; exit to CP/M
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end
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