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-int 0x10 teletype output cuts final character in custom MBR on QEMU (i386 real mode)
-Description of problem:
-When using QEMU to test a custom bootloader in 16-bit real mode (i386), the BIOS interrupt `int 0x10` with AH=0x0E (teletype output) fails to display the last character of the printed message. For example, printing `"hello"` only renders `"hell"`.
-
-This happens only with this exact combination:
-
-real mode `int 0x10` teletype output
-
-message ends with `13, 10, 0`
-
-`QEMU` output cuts off the last character consistently
-
-All buffer and code logic has been verified to be correct. The same code, when run on Bochs or physical hardware, prints properly.
-Steps to reproduce:
-1.Assemble the following boot.asm:
-```nasm
-[org 0x7C00]
-[BITS 16]
-
-_start:
-    cli
-    xor ax, ax
-    mov ds, ax
-    mov es, ax
-    mov ss, ax
-    mov sp, 0x7C00
-
-    mov si, msg
-    call print
-
-    hlt
-    jmp $
-
-print:
-    pusha
-.loop:
-    lodsb
-    or al, al
-    jz .done
-    mov ah, 0x0E
-    int 0x10
-    jmp .loop
-.done:
-    popa
-    ret
-
-msg db 'hello', 13, 10, 0
-times 510 - ($ - $$) db 0
-dw 0xAA55
-```
-
-2. Compile and run:
-```bash
-$ nasm -f bin boot.asm -o boot.img
-$ qemu-system-i386 -nographic -boot a -drive format=raw,file=boot.img,index=0,if=floppy
-```
-
-3. Output will be:
-```text
-Booting from Floppy...
-hell
-```
-Expected output:
-```text
-Booting from Floppy...
-hello
-```
-Additional information:
-- Adding padding (extra 13, 10) does not solve the problem.
-
-- Confirmed that boot.img includes all bytes (xxd dump is correct).
-
-- Tested on multiple machines with same QEMU version.
-
-- May relate to VGA character output buffer not flushing after last INT 0x10?
-
-- This makes QEMU inaccurate for BIOS-level debugging of bootloaders.