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Error loading bootloader and kernel

We are working on a project to learn how to write a kernel and learn everything. We have a boot loader loaded and it works. However, we have a problem loading the kernel. I will start with the first part:

bootloader.asm:

    [BITS 16]
    [ORG 0x0000]
;
;    all the stuff in between
;
;    the bottom of the bootstrap loader

     datasector  dw 0x0000
     cluster     dw 0x0000
     ImageName   db "KERNEL  SYS"
     msgLoading  db 0x0D, 0x0A, "Loading Kernel Shell", 0x0D, 0x0A, 0x00
     msgCRLF     db 0x0D, 0x0A, 0x00
     msgProgress db ".", 0x00
     msgFailure  db 0x0D, 0x0A, "ERROR : Press key to reboot", 0x00

     TIMES 510-($-$$) DB 0
     DW 0xAA55

     ;*************************************************************************

Boot. Startup is too long for the editor, without forcing it to intercept and suppress. In addition, the bootloader and the kernel work in barrels, as we get the message "Welcome to our OS." Anyway, the next kernel for the kernel at the moment.

kernel.asm:

[BITS 16]
[ORG 0x0000]

[SEGMENT .text]         ; code segment
    mov     ax, 0x0100          ; location where kernel is loaded
    mov     ds, ax
    mov     es, ax

    cli
    mov     ss, ax          ; stack segment
    mov     sp, 0xFFFF          ; stack pointer at 64k limit
    sti

    mov     si, strWelcomeMsg       ; load message
    call        _disp_str

    mov     ah, 0x00
    int     0x16                ; interrupt: await keypress
    int     0x19                ; interrupt: reboot

_disp_str:
    lodsb                       ; load next character
    or      al, al          ; test for NUL character
    jz      .DONE

    mov     ah, 0x0E            ; BIOS teletype
    mov     bh, 0x00            ; display page 0
    mov     bl, 0x07            ; text attribute
    int     0x10                ; interrupt: invoke BIOS

    jmp     _disp_str

.DONE:
    ret

[SEGMENT .data]                 ; initialized data segment
    strWelcomeMsg   db  "Welcome to our OS",    0x00

[SEGMENT .bss]              ; uninitialized data segment

Using nasm 2.06rc2, I compile as such:
nasm bootloader.asm -o bootloader.bin -f bin
nasm kernel.asm -o kernel.sys -f bin

We write the bootloader.bin file to the floppy disk as such:
dd if=bootloader.bin bs=512 count=1 of/dev/fd0

We write kernel.sys to the floppy disk as such:
cp kernel.sys /dev/fd0

As I said, this works in the barrel. But booting from a floppy disk turns out like this:


...........
:

: OpenSUSE 11.2, GNOME, AMD x64 , , , , . , . , . GRUB . , , , GRUB.

EDIT: 512 , ( ) . , 512 . .

+5
1

, kernel.sys , cp.

dd if=kernel.sys of=/dev/fd0 bs=512 seek=1

, bootloader.bin 512 , :

cat bootloader.bin kernel.sys > /dev/fd0
+3

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