.code16
.globl start

start:
    jmp boot

name:   .ascii "TESTOS"
sect_size:  .word 512
clust_size: .byte 1
rsvd_sects: .word 1
fat_cont:   .byte 2
root_ents:  .word 244
total_sect: .word 2880
media_type: .byte 0xf0
fat_size:   .word 9
trk_size:   .word 18
head_cont:  .word 2
hidd_sect:  .long 0
huge_sect:  .long 2880
boot_dev:   .byte 0
reserved:   .byte 0
signature:  .byte 0x28
vol_ID:     .long 0xffffffff
vol_label:  .ascii "DISK "
fat_name:   .ascii "FAT12 "
    .ascii "IPL 110105"
    .skip 18,0

boot:
    cli
    movw $0, %ax
    movw %ax, %ss
    movw $0x7c00, %sp
    movw %ax, %ds
    movw %ax, %es
    movw $msg, %si

loop:
    movb 0(%si), %al
    add $0x01, %si
    cmpb $0x00, %al
    je fin
    movb $0x0e, %ah
    movw $0x0015, %bx
    int $0x10
    jmp loop

fin:
    hlt
    jmp fin

msg:    .ascii "xxx Making OS is very difficult xxx"
        .byte 0

.org 510
.byte 0x55,0xaa