31 lines
806 B
NASM
31 lines
806 B
NASM
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[bits 32]
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VIDEO_MEMORY: equ 0xB8000
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WHITE_ON_BLACK: equ 0x0F
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;;;
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; print_string_pm
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; ------------
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; Print a string stored in memory.
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;
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; Parameters:
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; - ebx: pointer to string in memory
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print_string_pm:
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pusha
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mov edx, VIDEO_MEMORY ; set `edx' to the start of the video memory
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print_string_pm_loop:
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mov al, [ebx] ; store the char at `ebx' in `al'
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mov ah, WHITE_ON_BLACK ; store the attributes in `ah'
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cmp al, 0 ; if null-termination then done
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je print_string_pm_done
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mov [edx], ax ; store char and attributes
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add ebx, 1 ; increment ebx to next char
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add edx, 2 ; increment to next char cell in vidmem
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jmp print_string_pm_loop
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print_string_pm_done:
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popa
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ret
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