37 lines
987 B
NASM
37 lines
987 B
NASM
namespace string 67; my string namespace here
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word FRAMEBUFFER 0x00200500
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asciiz Msg "Hello World!"
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; fn effectively is an "Append to Namespace" command, ie string + "." + _start
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fn _start:
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mov FRAMEBUFFER, r32 ; imm, r
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mov msg, r1 ; imm, r
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call strlen ; result into r2
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mov 0, r4 ; counter
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loop:
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mov byte [r1], r3 ; read char into r3
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cmp r3, 0 ; NUL byte?
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je end
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mov byte r3, [r32] ; Write char to frame buffer
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inc r32 ; Next space in framebuffer
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inc r4 ; inc counter
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inc r1 ; inc pointer to msg
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jmp loop
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end: ;At the moment this just writes Msg to the framebuffer.
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ret
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; Clobbers r2, r3
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; Params: r1 - string pointer
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; Returns: r2, string length
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fn strlen:
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mov 0, r2 ; Set the length to zero
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loop:
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mov byte [r1], r3 ; mov char into r3
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cmp r3, 0 ; NUL byte?
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je end
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inc r1 ; next char
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inc r2 ; length++
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jmp loop
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end:
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ret |