75 lines
1.2 KiB
NASM
75 lines
1.2 KiB
NASM
bits 16 ; mode 16bits
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org 0x7C00 ; mbr ae loaded at 0x7C00
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jmp boot
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display_enable:
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push bp
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mov bp, sp
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mov ah, 0h ; 00h Set Video Mode
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mov al, 07h ; Txt, monochrome, 80x25
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int 10h
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mov sp, bp
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pop bp
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ret
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print:
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push bp
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mov bp, sp
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mov si, [bp + 4]; put first function arg in si. sp is stask pointer
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.loop:
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lodsb ; load si content into al then inc si
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cmp al, 0;
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je .end
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mov ah, 0eh
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mov bx, 0
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int 10h
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jmp .loop
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.end:
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mov sp, bp
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pop bp
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ret
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println:
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push bp
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mov bp, sp
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push word [bp + 4]
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call print
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add sp, 2
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mov ah, 03h ; read cursor position
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int 10h ; row number in dh. Col in dl
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inc dh ; goto next line
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mov dl, 0
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mov ah, 02h ; Set Cursor Position
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int 10h
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mov sp, bp
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pop bp
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ret
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hello db 'Hello world', 0
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name db 'This is a name', 0
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boot:
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sti ; enable virtual interupts
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call display_enable
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push hello
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call println
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add sp, 2
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push name
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call println
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add sp, 2
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times 510 - ($ - $$) db 0 ; fill up to 510 with 0
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dw 0xAA55 ; MBR magic number
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