71 lines
1.8 KiB
ArmAsm
71 lines
1.8 KiB
ArmAsm
[bits 16] ; 16 bit real mode code
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[org 0x7C00] ; Origin at 0x7C00 (upper end of memory)
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start:
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call blankScreen
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mov dx, 0x0
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call setCursorPosition
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mov si, _str_hello ; si = source index
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call printString
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mov dh, 0x1
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mov dl, 0x0
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call setCursorPosition
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mov al, 0x17 ; read the remaining 16 tracks
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mov ch, 0x1 ; .... on track 1 ....
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mov cl, 0x1 ; .... starting at sector 1
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mov bx, 0x1000 ; 0x1000 is a standard kernel start location
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mov es, bx
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xor bx, bx ; bx = 0, es:bs = 0x1000:0
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call loadFloppyDiskSectors
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push ax
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mov ax, bx
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add ax, 0x2200 ; we just read 0x2200 bytes, move pointer in memory
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mov bx, ax
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pop ax
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mov al, 0x17 ; read 18 sectors per track for all future tracks
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mov cl, 0x1 ; start at sector 1 for all future tracks
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mov di, 0x2FF ; abuse di as a counter, while (di < 80)
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; di is technically a destination index for stream
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; ops, but nothing is using it ATM, so gimme.
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_next_floppy_track:
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push ax
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mov ax, 0x2e
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call printCharacter
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mov ax, cx
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mov cx, di
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mov cl, al
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pop ax
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call loadFloppyDiskSectors
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push ax
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mov ax, bx
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add ax, 0x2400 ; each floppy track is (512b*18s)=0x2400 bytes long
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mov bx, ax
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pop ax
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inc di
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push cx
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mov cx, 0x50
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cmp di, cx ; di < 80 ?
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jg _end_floppy_read
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pop cx
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_end_floppy_read:
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mov dh, 0x1
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mov dl, 0x0
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call setCursorPosition
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mov si, _str_floppydone
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call printString
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jmp 0x1000
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%include "libinterrupt.S"
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_str_hello db 'Piquant v0.1 Bootloader', 0xA, 0
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_str_loading db 'Loading', 0
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_str_floppydone db 'Kernel loaded', 0xA, 0
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times 510 - ($ - $$) db 0 ; fill up to 510 bytes with 0
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dw 0xAA55 ; magic bootloader signature
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