73 lines
1.9 KiB
ArmAsm
73 lines
1.9 KiB
ArmAsm
[bits 16] ; 16 bit real mode code
|
|
[org 0x7C00] ; Origin at 0x7C00 (upper end of memory)
|
|
|
|
start:
|
|
call blankScreen
|
|
|
|
mov dx, 0x0
|
|
call setCursorPosition
|
|
|
|
mov si, _str_hello ; si = source index
|
|
call printString
|
|
mov dh, 0x1
|
|
mov dl, 0x0
|
|
call setCursorPosition
|
|
|
|
mov al, 0x1 ; read the remaining 16 tracks
|
|
mov ch, 0x0 ; .... on track 0 ....
|
|
mov cl, 0x2 ; .... starting at sector 2
|
|
mov bx, 0x1000 ; 0x1000 is a standard kernel start location
|
|
mov es, bx
|
|
mov bx, 0x0 ; bx = 0, es:bx = 0x1000:0
|
|
call loadFloppyDiskSectors
|
|
;; push ax
|
|
;; mov ax, bx
|
|
;; add ax, 0x2200 ; we just read 0x2200 bytes, move pointer in memory
|
|
;; mov bx, ax
|
|
;; pop ax
|
|
;; mov al, 0x17 ; read 18 sectors per track for all future tracks
|
|
;; mov cl, 0x1 ; start at sector 1 for all future tracks
|
|
|
|
;; mov di, 0x2FF ; abuse di as a counter, while (di < 80)
|
|
;; ; di is technically a destination index for stream
|
|
;; ; ops, but nothing is using it ATM, so gimme.
|
|
;; _next_floppy_track:
|
|
;; push ax
|
|
;; mov ax, 0x2e
|
|
;; call printCharacter
|
|
;; mov ax, cx
|
|
;; mov cx, di
|
|
;; mov cl, al
|
|
;; pop ax
|
|
;; call loadFloppyDiskSectors
|
|
;; push ax
|
|
;; mov ax, bx
|
|
;; add ax, 0x2400 ; each floppy track is (512b*18s)=0x2400 bytes long
|
|
;; mov bx, ax
|
|
;; pop ax
|
|
;; inc di
|
|
;; push cx
|
|
;; mov cx, 0x50
|
|
;; cmp di, cx ; di < 80 ?
|
|
;; jg _end_floppy_read
|
|
;; pop cx
|
|
|
|
_end_floppy_read:
|
|
mov dh, 0x1
|
|
mov dl, 0x0
|
|
call setCursorPosition
|
|
mov si, _str_floppydone
|
|
call printString
|
|
jmp _extern_c_main
|
|
|
|
%include "libinterrupt.S"
|
|
%include "kernel_syms.S"
|
|
|
|
_str_hello db 'Piquant v0.1 Bootloader', 0xA, 0
|
|
_str_loading db 'Loading', 0
|
|
_str_floppydone db 'Kernel loaded', 0xA, 0
|
|
|
|
times 510 - ($ - $$) db 0 ; fill up to 510 bytes with 0
|
|
dw 0xAA55 ; magic bootloader signature
|
|
|