I am building a bootloader in nasm, I have been able to detect tab, enter, and backspace keys, but arrow keys won't work no matter what hex scan values I try.
I've tried the values here: What are the scan codes for keyboard arrows? (right,left,down,up) as well as many other google results (none of them matching each other), but it won't work, all it prints is a space, the code that should be running after it detects left arrow isn't running at all.
BITS 16
mov ah, 0h
int 10h
mov ah, 2h
mov dl, 0
mov dh, 0
int 10h
mov bl, 2 ; color
pop ds
global _start
_start:
jmp .character_read
.character_read:
mov ah,00h ;remeber set the value to "ah" now you are going to read a keyboard input
int 16h ;this interrupt is given to control keystrokes of keyboard
cmp al, 0x08 ; if key is backspace
je _backspace ; go to the section controling removing characters
cmp al, 0x0D
je _enter
cmp al, 0x4B ; where it should detect left arrow
je _back_cursor
jmp .print_input
.print_input:
mov ah,9h ;set the value to "ah" to print one character to std out
mov cx,1 ;set the value how many time the character in "al" should be print
int 10h
jmp _forward_cursor
_backspace:
mov ah, 2h
dec dl
int 10h
mov ah, 9h
mov cx, 1
mov al, ""
int 10h
jmp _start
_enter:
jmp _inc_col
_back_cursor:
mov ah, 2h
dec dl
int 10h
jmp _start
_forward_cursor:
mov ah, 2h
inc dl
int 10h
cmp dl, 80
je _inc_col
jne _start
_home:
mov ah, 2h
xor dl, dl
int 10h
jmp _start
_inc_col:
mov ah, 2h
xor dl, dl
inc dh
int 10h
jmp _start
TIMES 510 - ($-$$) db 0
dw 0aa55h
I am on an HP Probook 6470b, with kali OS and qemu 7.1.0 as my emulator. Is this a problem with my code? or qemu?
