28 lines
751 B
NASM
28 lines
751 B
NASM
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[bits 16]
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i_disk16_error_message: db "Disk read error!", 0
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disk16_load:
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push dx ; keep track of the # of sectors requested to be read
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mov ah, 0x02 ; bios read sector
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mov al, dh ; read dh # sectors
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mov ch, 0x00 ; select cylinder 0
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mov dh, 0x00 ; select head 0
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mov cl, 0x02 ; start reading from 2nd sector
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; (i.e. the sector after the boot sector)
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int 0x13 ; bios interrupt to trigger read
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jc disk16_on_error ; jump if carry (fault) flag was set
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pop dx ; restore original # of registers in case it was modified
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cmp dh, al ; compare # sectors read (al) to # sectors expected (dh)
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jne disk16_on_error ; error if # sectors differs
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ret
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disk16_on_error:
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mov bx, i_disk16_error_message
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call print16
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jmp g_infinite_loop
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