x86: INT 13h does not read from the disk

I tried to load kernel stored on floppy disk formatted to FAT12. When I try to read sectors where kernel is located, I don't have any errors (carry flag is not set), but memory where I try to load the kernel has zeroes.

org 0x7C00bits 16%define endl            0x0D, 0x0A%define dirEntrySize        32%define fatLocation     0x7E00%define rootdirLocation     0x9000%define kernelLocation      0x9E00%define filenameLength      11jmp short mainnop; BPB and EBR data hererootdirStart:           dw 0dataStart:          dw 0main:    xor ax, ax    mov ds, ax    mov es, ax    mov ss, ax    mov sp, 0x7C00    mov [ebr_driveNumber], dl    mov si, msg_loading    call puts    ; Read FAT    mov ax, [bpb_reservedSectors]    mov bx, fatLocation    mov cx, [bpb_sectorsPerFat]    call readSectors    ; Read Root Directory    mov ax, [bpb_rootdirEntries]    mov bx, dirEntrySize    mul bx    div word [bpb_bytesPerSector]    mov [dataStart], ax    xchg ax, cx    mul byte [bpb_fatCount]    add ax, [bpb_reservedSectors]    mov bx, rootdirLocation    call readSectors    mov [rootdirStart], ax    add [dataStart], ax    ; Find and read the kernel    mov si, kernelFilename    call findFile    mov bx, kernelLocation    call readFile    ; Load kernel    mov dl, [ebr_driveNumber]    jmp kernelLocation    cli    hlt; putc and puts functionslbaToChs:    push ax    push dx    xor dx, dx    div word [bpb_sectorsPerTrack]    inc dx    mov cx, dx    xor dx, dx    div word [bpb_headCount]    mov dh, dl    mov ch, al    shl ah, 6    or cl, ah    pop ax    mov dl, al    pop ax    retreadSectors:    push ax    push cx    push dx    push si    push di    push cx    call lbaToChs    pop si    mov di, 3    mov dl, [ebr_driveNumber].loop:    mov ah, 0x02    int 0x13    mov ah, 0x01    int 0x13    jnc .done    mov ah, 0x00    int 0x13    dec di    jz .fail    dec si    jnz .loop.done:    pop di    pop si    pop dx    pop cx    pop ax    ret.fail:    mov si, msg_diskError    call puts    cli    hlt; findFile functionreadFile:    push ax    push bx    push cx    push dx.loop:    push ax    sub ax, 2    mul byte [bpb_sectorsPerCluster]    add ax, word [dataStart]    mov cx, 1    call readSectors    mov ax, [bpb_bytesPerSector]    mul byte [bpb_sectorsPerCluster]    add bx, ax    pop ax    mov cl, 3    mul cx    dec cl    div cx    mov si, fatLocation    add si, ax    mov ax, [si]    or dx, dx    jnz .odd.even:    and ax, 0x0FFF    jmp .update.odd:    shr ax, 4.update:    cmp ax, 0xFF0    jnl .loop.done:    pop dx    pop cx    pop bx    pop ax    ret.fail:    mov si, msg_loadFailed    call puts    cli    hltkernelFilename: db "KERNEL  BIN"msg_loading: db "Loading...", endl, 0msg_findFailed: db "Cannot find kernel", 0msg_loadFailed: db "Cannot load kernel", 0msg_diskError: db "Disk error", 0times 510+$$-$ db 0dw 0xAA55

I tried debugging with GDB and checked the registers, but their value was correct. I also checked the memory where I stored the FAT and the Root Directory, but this data also was correct. Only the memory where I wanted to load kernel was filled with zeroes.

Register values after lba-to-chs conversion:

eax            0x21                33ecx            0x10                16edx            0x100               256ebx            0x9e00              40448esp            0x7be6              0x7be6ebp            0x0                 0x0esi            0x7d98              32152edi            0x0                 0eip            0x7ce6              0x7ce6eflags         0x202               [ IOPL=0 IF ]cs             0x0                 0ss             0x0                 0ds             0x0                 0es             0x0                 0fs             0x0                 0gs             0x0                 0

AX value is correct, should be lba of start of data: reserved_sectors + sectors_per_fat * fat_count + root_dir_entries * dir_entry_size / bytes_per_sectors = 1 + 9 * 2 + 224 * 32 / 512 = 1 + 18 + 14 = 33. In floppy image opened with hex editor, that points to start of the kernel.

Loaded file allocation table:

0x7e00: 0xf0    0xff    0xff    0xff    0x0f    0x00    0x00    0x000x7e08: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x00...

Loaded root directory:

0x9000: 0x4b    0x45    0x52    0x4e    0x45    0x4c    0x20    0x200x9008: 0x42    0x49    0x4e    0x20    0x18    0x00    0x28    0x610x9010: 0xaa    0x58    0xaa    0x58    0x00    0x00    0x28    0x610x9018: 0xaa    0x58    0x02    0x00    0x25    0x01    0x00    0x000x9020: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x000x9028: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x000x9030: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x000x9038: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x00...

*Loaded* kernel:

0x9e00: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x000x9e08: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x000x9e10: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x000x9e18: 0x00    0x00    0x00    0x00    0x00    0x00    0x00    0x00...