Add boot.asm
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; boot.asm - A simple bootloader example
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[bits 16] ; Set to 16-bit mode
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[org 0x7C00] ; BIOS loads the bootloader at this address
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start:
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; Clear screen
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mov ax, 0x0003 ; Set video mode to 3 (80x25 color text)
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int 0x10 ; BIOS interrupt to set video mode
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; Print "Hello, World!"
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mov si, hello_message ; Load address of the message into SI
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call print_string ; Call function to print the string
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; Hang the system (infinite loop)
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hang:
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jmp hang ; Jump to hang indefinitely
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; Function to print a string
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print_string:
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mov ah, 0x0E ; BIOS teletype output function
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.next_char:
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lodsb ; Load byte at DS:SI into AL and increment SI
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cmp al, 0 ; Check for null terminator
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je .done ; If null, we are done
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int 0x10 ; Call BIOS to print character in AL
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jmp .next_char ; Repeat for next character
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.done:
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ret ; Return from function
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; Data section
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hello_message db 'Hello, World!', 0 ; Null-terminated string
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; Bootloader signature (must be present)
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times 510 - ($ - $$) db 0 ; Fill the rest of the sector with zeros
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dw 0xAA55 ; Boot signature
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