50 lines
913 B
NASM
50 lines
913 B
NASM
;; File: floppy.asm
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format binary
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use16
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include '../common/const.inc'
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include '../common/macro.inc'
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jmp short _start
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OEM_identifier db 'STUPID '
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bytes_per_sector dw 512
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sectors_per_cluster db 0
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reserved_sectors dw 0
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FAT_count db 0
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root_dir_entries dw 0
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total_sectors dw 0
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media_desc_type db 0
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sectors_per_FAT dw 0
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sectors_per_track dw 18
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heads_per_cylinder dw 2
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hidden_sectors dd 0
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large_sector_count dd 0
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; Extended Boot Record
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drive_number db 0
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reserved db 0
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signature db 0
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volume_id dd 0xB00B135 ; hope mine will grow :'(
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volume_label db 'Stupid Boot'
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system_id db ' '
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_start:
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mov [drive_number], dl
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; ensure int 13h extension
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mov ah, 0x41
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mov bx, 0x55AA
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int 0x13
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jc .error_lba
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.error_lba:
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mov si, msg_error_13ext
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jmp .error_print
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msg_error_13ext db "We don't support CHS", CR, LF, 0
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rb 0x7C00+512-2-$
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db 0x55, 0xAA
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