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; NOF_SECTORS_STAGE2
NOF_SECTORS_STAGE2 equ 5
; IN dx: hex value to print
print_hex:
push bx
push si
mov si, HEX_TEMPLATE
mov bx, dx
shr bx, 12
mov bx, [HEXABET+bx]
mov [HEX_TEMPLATE+2], bl
mov bx, dx
and bx, 0x0FFF
shr bx, 8
mov bx, [HEXABET+bx]
mov [HEX_TEMPLATE+3], bl
mov bx, dx
and bx, 0x00FF
shr bx, 4
mov bx, [HEXABET+bx]
mov [HEX_TEMPLATE+4], bl
mov bx, dx
and bx, 0x000F
mov bx, [HEXABET+bx]
mov [HEX_TEMPLATE+5], bl
call print_string
pop si
pop bx
ret
HEX_TEMPLATE:
db '0x???? ', 0
HEXABET:
db '0123456789ABCDEF'
print_newline:
push ax
mov al, 10
call print_char
mov al, 13
call print_char
pop ax
ret
; IN si
print_string:
push ax
.loop:
lodsb
cmp al, 0
je .fini
call print_char
jmp .loop
.fini:
pop ax
ret
; IN al: character to print
; MOD ah
print_char:
mov ah, 0x0e
int 0x10
ret
fat_cursor:
push ax
push cx
mov ah, 0x01
mov cx, 0x0007
int 0x10
pop cx
pop ax
ret
; OUT: current row
current_row:
push ax
push bx
push cx
mov ah, 0x03
mov bh, 0
int 0x10
pop cx
pop bx
pop ax
ret
; IN dl: drive to read from
read_stage2_from_disk:
mov ah, 0x02 ; read sectors from drive
mov al, NOF_SECTORS_STAGE2 ; read sectors of stage 2
mov ch, 0 ; select first cylinder
mov dh, 0 ; first head
mov cl, 2 ; second sector after boot sector
mov bx, 0 ; where to store the data
mov es, bx
mov bx, 0x7e00 ; 512 bytes after first sector
int 0x13
jc .read_error
cmp al, NOF_SECTORS_STAGE2 ; correct number of sectors read?
jne .short_read ; if not, short read
ret
.read_error:
mov si, DISK_ERROR
call print_string
mov dh, 0
mov dl, ah
call print_hex
jmp $
.short_read:
mov si, SHORT_READ
call print_string
jmp $
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