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7c0f9d0477
Text pointer with 'Hello, World!' string is located at RAM and string could be changed during the runtime. Uses functions ECHO and RESET of Woz OS from Apple-1, so could be easily run in emulator.
26 lines
439 B
NASM
26 lines
439 B
NASM
;printing 'Hello, World!' at a runtime demo
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;More about 'Hello, World!' program: https://en.wikipedia.org/wiki/%22Hello,_World!%22_program
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RESET = $FF00
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ECHO = $FFEF
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TXTPTR = $1000
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.org $1000
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.byte $0d
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.ASCII "Hello, World!"
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.byte $0d
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.byte $00
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.org $2000
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LDX #00
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PRINT_CHAR:
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LDA TXTPTR,X
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BEQ END_PRINT ;end printing at the end of the string (\n=0)
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JSR ECHO
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INX
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JMP PRINT_CHAR
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END_PRINT:
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JMP RESET ;return to Woz Monitor
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