Bogus int 13h error 0xc in qemu?

[clementttttttttt]

For some reasons, int 13h is still setting the carry flag and complaining about "media type not found" in qemu, even though I can prove that the sectors are correctly loaded.

[Octocontrabass]

It's hard to say what's wrong without seeing your code.

[clementttttttttt]

code is attached as file.

[wxwisiasdf]

code is attached as file.

You're not clearing flags before calling INT 0x13. This is a big nono. INT 0x13 calls are known to assume that the carry flag is clear when it is not. They also love to destroy BP.

[Octocontrabass]

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.nsectors dw 16

You're reading 16 sectors. Does your disk have 16 sectors for you to read?

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    mov sp,0x4000
    xor ax,ax
    mov ss,ax

An interrupt can happen between setting SP and setting SS. Rearrange these instructions so that the MOV to SP immediately follows the MOV to SS, or disable interrupts with CLI.

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    lgdt [gdtinfo]
    pop ds
    mov ah,0x41
    mov bx,0x55aa
    mov dl,0x80
    int 13h

Support for the EDD functions will vary depending on the drive number in DL. You must specify the same number in DL that you use for later calls.

You make BIOS calls between loading the GDTR and switching to protected mode. BIOS calls may modify the GDTR.

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    int 13h
    cli
    cmp ah,0xc
    je skip
    jc error

The CMP instruction modifies the carry flag.

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	lodsb

You need to clear the direction flag.

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    mov ax,0x4f02
    mov bx,0x4113
    int 10h

This won't work on some hardware.

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    and al,0xfe
    mov cr0,eax
    jmp $

You need a far JMP after a MOV to CR0 that modifies CR0.PE.