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https://github.com/cfenollosa/os-tutorial.git
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27 lines
598 B
NASM
27 lines
598 B
NASM
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[bits 32] ; using 32-bit protected mode
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; this is how constants are defined
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VIDEO_MEMORY equ 0xb8000
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WHITE_OB_BLACK equ 0x0f ; the color byte for each character
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print_string_pm:
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pusha
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mov edx, VIDEO_MEMORY
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print_string_pm_loop:
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mov al, [ebx] ; [ebx] is the address of our character
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mov ah, WHITE_OB_BLACK
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cmp al, 0 ; check if end of string
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je print_string_pm_done
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mov [edx], ax ; store character + attribute in video memory
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add ebx, 1 ; next char
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add edx, 2 ; next video memory position
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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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