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30 lines
1016 B
NASM
30 lines
1016 B
NASM
1 year ago
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; Multiply 7 with 10 and print the result
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; For testing this program was assembled with c64 (using the -R option):
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; https://www.aartbik.com/MISC/c64.html
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; FAST MULTIPLY program from:
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; http://6502.org/source/integers/fastx10.htm
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main LDA #7 ; load 7 into the accumulator
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ASL ;multiply by 2
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STA TEMP ;temp store in TEMP
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ASL ;again multiply by 2 (*4)
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ASL ;again multiply by 2 (*8)
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CLC
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ADC TEMP ;as result, A = x*8 + x*2
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; PRINT RESULT
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STA $A0 ; 0x85, 0xA0, ; store A into the console output address
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LDX #0 ; 0xA2, 0x00, ; null terminator
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STX $A1 ; 0x86, 0xA1, ; store null terminator to output addr + 1
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; Set flag to do the print
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LDX #1 ; 0xA2, 0x01,
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STX $9F ; 0x86, 0x9F, ; Print byte flag is at 0x9F
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; End the program
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RTS ; 0x60
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; Variables
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TEMP .byte 0
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