[org 0x7c00]

[bits 16]

pre:
cmp ah, 0x0F ; checking if coming from other app or first load - setting ah to 0F before jmping back to the bootloader
je welcome
mov [bootdev], dl		; Save boot device number
jmp welcome

welcome:
    xor ax,ax      ; We want a segment of 0 for DS for this question
    mov ds,ax      ;     Set AX to appropriate segment value for your situation
    mov es,ax      ; In this case we'll default to ES=DS
    mov bx,0x8000  ; Stack segment can be any usable memory
    mov ss,bx      ; This places it with the top of the stack @ 0x80000.
    mov sp,ax      ; Set SP=0 so the bottom of stack will be @ 0x8FFFF
    cld            ; Set the direction flag to be positive direction



        mov ah, 01h     ;make cursor invisible
        mov cx, 2607h
        int 10h

    mov ah, 06h    ; Set overall background
    xor al, al     ; and clear entire screen
    xor cx, cx     ; Upper left corner CH=row, CL=column = 0
    mov dx, 184Fh  ; lower right corner DH=row, DL=column = 25 x 80 / textmode
    mov bh, 1Eh    ; YellowOnBlue
    int 10h


        mov ah, 06h; top bar, make background
	xor cx, cx
	mov dx, 0x004F
	mov bh, 30h
	int 10h


        mov ah, 02h ;top bar setting the position and then write title to it
        mov bh, 0h
        mov dh, 0h
        mov dl, 20h
        int 10h

        mov si, title
        call wolf_print


	mov ah, 06h; bottom bar, make background
        mov cx, 0x1800
        mov dx, 0x184F
        mov bh, 30h
        int 10h


        mov ah, 02h ;bottom bar setting the position and then write title $
        mov bh, 0h
        mov dh, 18h
        mov dl, 20h
        int 10h

        mov si, title
        call wolf_print


        mov ah, 02h     ;sets cursor to top to write
        mov bh, 0h
        mov dh, 2h
        mov dl, 2h
        int 10h

	mov si, wolf_wel_msg
	call wolf_print

;	mov si, xpub
;	call wolf_print

start:
	mov ah, 0x00
        int 0x16
        cmp al, "0"
        je load_it_all_0
        cmp al, "1"
	je load_it_all_1
	jmp over

load_it_all_0:

    mov si, wolf_kernel_load
    call wolf_print

    pushf
    stc

    mov ah,00
    int 13h

.read_sector:
        mov ax, 0x0
        mov es, ax      ; ES = 0
        mov bx, 0x2000  ; BX = 0x1000. ES:BX=0x0:0x1000
                        ; ES:BX = starting address to read sector(s) into
        mov ah, 02      ; Int 13h/AH=2 = Read Sectors From Drive
        mov al, 01      ; Sectors to read = 1
        mov ch, 00      ; CH=Cylinder. Second sector of disk
                        ; is at Cylinder 0 not 1
        mov cl, 03      ; Sector to read = 2
        mov dh, 00      ; Head to read = 0
                        ; DL hasn't been destroyed by our bootloader code and still
                        ;     contains boot drive # passed to our bootloader by the BIOS
	mov dl, [bootdev]
        int 13h

    jc wolf_error
    popf
    jmp 0x0:0x2000
    cli
    hlt


load_it_all_1:

    mov si, wolf_kernel_load
    call wolf_print

    pushf
    stc

    mov ah,00
    int 13h

.read_sector:
        mov ax, 0x0
        mov es, ax      ; ES = 0
        mov bx, 0x1000  ; BX = 0x1000. ES:BX=0x0:0x1000
                        ; ES:BX = starting address to read sector(s) into
        mov ah, 02      ; Int 13h/AH=2 = Read Sectors From Drive
        mov al, 01      ; Sectors to read = 1
        mov ch, 00      ; CH=Cylinder. Second sector of disk
                        ; is at Cylinder 0 not 1
        mov cl, 02      ; Sector to read = 2
        mov dh, 00      ; Head to read = 0
                        ; DL hasn't been destroyed by our bootloader code and still
                        ;     contains boot drive # passed to our bootloader by the BIOS
	mov dl, [bootdev]
	int 13h

    jc wolf_error
    popf
    jmp 0x0:0x1000
    cli
    hlt


wolf_error:
        mov si, wolf_error_msg
        call wolf_print
        mov si, wolf_error_msg1
        call wolf_print
        mov ah,00
        int 16h
        xor ax,ax
        int 19h

wolf_print:
        lodsb
        or al,al
        jz exit
	mov ah,0x0e
        int 10h
        jmp wolf_print
        exit:
        ret



over:
        jmp start

; Moved the data before the boot signature but after the code
wolf_wel_msg db 'Welcome to this publication..., press a key to ENTER',0x0D,0x0A,0
wolf_kernel_load db 'Loading program',0x0D,0x0A,0
wolf_error_msg db 'Program not found!',0x0D,0x0A,0
wolf_error_msg1 db 'Press any key to restart..',0
;xpub db 0x0D, 0x0A, 0x20, 0xB1, 0x20, 0x20, 0x20, 0xB1, 0x20, 0xB1, 0xB1, 0xB1, 0x20, 0x20, 0xB1, 0x20, 0x20, 0x20, 0xB1,0x20,0xB1,0xB1,0xB1, 0x20, 0x0D, 0x0A,0x20,0x20,0xB1,0x20,0xB1,0x20,0x20,0xB1,0x20,0x20,0xB1, 0x20,0xB1,0x20,0x20,0x20,0xB1,0x20,0xB1,0x20,0x20, 0xB1, 0x0D,0x0A,0x20,0x20,0x20,0xB1, 0x20,0x20,0x20,0xB1,0xB1, 0xB1,0x20,0x20,0xB1,0x20,0x20,0x20,0xB1,0x20,0xB1,0xB1,0xB1,0x20,0x0D,0x0A,0x20,0x20,0xB1,0x20,0xB1, 0x20,0x20,0xB1,0x20,0x20,0x20,0x20,0xB1,0x20,0x20,0x20,0xB1,0x20,0xB1,0x20,0x20,0xB1,0x0D,0x0A,0x20,0xB1, 0x20,0x20,0x20,0xB1,0x20,0xB1,0x20,0x20,0x20,0x20,0x20,0xB1,0xB1,0xB1,0x20,0x20,0xB1,0xB1,0xB1, 0x20, 0
title db 'NOT MY DEFAULT',0

bootdev		db 0x80 	; Boot device number

times 510-($-$$) db 0
dw 0xAA55