45 lines
1.1 KiB
NASM
45 lines
1.1 KiB
NASM
.org 0x100
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.db msg "Hello, world!", 0
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.db more_stuff "And yet another string!", 0
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copy r1, msg
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copy r2, 0
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loop:
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cmp r1, 0
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jz loop
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add r1, 1
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mov r1, 5 ; move the immediate value 5 into r1
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add r1,5 ; add 5 into r1
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int 21 ; maybe that will call some string drawing BIOS-like routine
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ret
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; form YYYY YYXX - Y opcode, X modifier
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; nop: 0000 0000
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; copy: 0000 01XX
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; add: 0000 10XX - | Perhaps running these will clear any overflow
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; addc: 0000 11XX - | or under flow flags if no errors occur.
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; sub: 0001 00XX - | jz should clear the zero flag.
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; subb: 0001 01XX - |
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; call: 0001 1100 - Always call [imm16]
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; jmp: 0010 0000 - Always jmp [imm16] (No short jumps)
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; jz: 0010 0100 - Always jz [imm16] (no short jumps)
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; cmp: 0010 11XX
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; push: 0011 11XX -| pop / push imm16/imm8 | reg
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; pop: 0100 00XX -|
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;
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; imm8 imm16 reg
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; mov reg, imm16|reg
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; add reg, imm16|reg
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; int imm16
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; db [label] 'String data here' (Null byte is added implicatly by the assemblier)
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;
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; enum Type {
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; Op,
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; Reg,
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; Imm16,
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; Imm8
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; }
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; struct Token {
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; enum Type type;
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; char *value;
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; } |