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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;; Miguel's FoolOS Helper Functions ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;
;disk_load_16
;
[bits 16]
STR_LBA:
db "\nLBA Support Detected (no support yet)",0
STR_CHS
db "CHS Support Detected",0
STR_ERROR
db "Disk Read Error",0
STR_DONE
db "Stage 2 Loaded",0
disk_load_16:
pusha
; check if LBA is supported
mov ah,0x41
mov bx,0x55aa
int 0x13
jnc disk_load_lba
jmp disk_load_chs
disk_load_lba:
mov bx, STR_LBA
call print_string
call print_nextline
jmp $
jmp disk_load_finish
disk_load_chs:
mov bx, STR_CHS
call print_string
call print_nextline
mov bx,0 ;target es:bx
mov es,bx
mov bx,0x7e00
mov al,50 ;number of sectors to read
mov ah,0x02 ;BIOS read sector func
mov cl,2 ; sector
mov ch,0 ; cylinder
mov dl,[BOOT_DRIVE]
mov dh,0 ;head
int 0x13 ;bios interrupt
jnc disk_load_finish
jmp $
disk_load_finish:
call print_nextline
mov bx, STR_DONE
call print_string
call print_nextline
popa
ret
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