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Hello !!

This site is very interresting

I try to start a simple c code from floppy sector boot.
My simple boot code run but the c code doesn't work.

Boot Code

;; bootsect.asm
;;
;; x86 boot code

[BITS 16]
[org 0x07c00]




jmp startb

startb:
;; Update the segment registers

mov ax, cs
mov ds, ax
mov es, ax

mov ah, 9 ; display =
mov al, '='        ; char
mov bx, 7 ; bh/bl
mov cx, 4 ; replicate caracter
int 10h

jmp reset

reset:
mov ah, 9
mov al, '>'
mov bx, 7
mov cx, 2
int 10h

mov ax, 0
mov dl, 0
int 13h
jc reset

jmp read

read:
mov ah, 9
mov al, '+'
mov bx, 7
mov cx, 2
int 10h

mov ax, 0x1000
mov es, ax
mov bx, 0

mov ah, 2 ;  mode 2
mov al, 2 ;  load n sectors
mov ch, 0 ;  cylinder 0
mov cl, 2 ;  sector 2
mov dh, 0 ;  head=0
mov dl, 0 ;  drive =0
int 13h

jc read

mov ah, 9
mov al, 'o'
mov bx, 7
mov cx, 2
int 10h


jmp 0x1000:0x0000


times 510-($-$$) db 0
dw 0AA55h


C code: mytest.c

int go (void)
{  
    //PRINT_CHAR;

    __asm__("
         mov 9, %ah
         mov 's', %al
         mov 7, %bx
         mov 2, %cx
         int $0x10
        ");
    return 0;
}


Building and loading:
  Boot
     nasm -f bin bs2.asm
     dd if=bs2 of=/dev/fd0 bs=512 count=1

  C code
gcc -ffreestanding -O2 -c mytest.c -o mytest.o -nostdlib -fno-uiltin -Wall

ld  -o mytest mytest.o -Ttext=0x1000 --oformat binary
dd if=mytest of=/dev/fd0 bs=512 count=2 seek=1

Have you an idea about my problem

Thanks in advance

xixam

gcc produce 32bit, protected mode code.

Thanks