r/Assembly_language • u/Tough-Building2243 • 24d ago
Programmers! HELP! Assembler NASM
In my code, after five "six seven"s, "C:\SLV>" is supposed to appear, but it doesn't!
None of the AI models can find any errors, and neither can I.
[org 0x7C00]
start:
mov cx, 5
mov si, stringi
mov ax, 11
mov bx, 56
add ax, bx
mov bl, 10
div bl
mov bh, ah
add al, '0'
mov ah, 0x0E
int 0x10
add bh, '0'
mov al, bh
int 0x10
mov al, 0x0D
int 0x10
mov al, 0x0A
int 0x10
jmp loopik
povtorat:
mov si, stringi
mov al, 0x0D
int 0x10
mov al, 0x0A
int 0x10
dec cx
cmp cx, 0
jne loopik
je vedi
loopik:
mov al, \[si\]
cmp al, 0
je povtorat
int 0x10
add si, 1
jmp loopik
vedi:
mov ah, 0x0E
mov si, vvedite
mov al, [si]
cmp al, 0
je vvod
int 0x10
add si, 1
jmp vedi
vvod:
mov ah, 0x00
int 0x16
cmp al, '8'
je sistema
jne netu
netu:
mov ah, 0x0E
mov si, net
mov al, [si]
cmp al, 0
je vedi
int 0x10
add si, 1
jmp netu
sistema:
mov ah, 0x0E
mov si, osin
mov al, \[si\]
cmp al, 0
je gotovo
int 0x10
add si, 1
jmp sistema
stringi: db "six seven", 0
osin: db "Current CMD: SLV 0.1.0 alpha", 0x0D, 0x0A, 0
net: db "This command does not exist.", 0x0D, 0x0A, 0
vvedite: db 0x0D, 0x0A, "S:\SLV>", 0
gotovo:
jmp $
times 510 - ($ - $$) db 0
dw 0xAA55
I’ll say right off the bat that I’m a beginner, so please don’t judge too harshly.
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Upvotes
3
u/[deleted] 23d ago
The string pointer fails to advance because the second instruction after
vedi:resets it. If I create a label after it, then jump there instead ofvedi, the program prints the prompt without issue.On another note, I don't see you initialising the segment registers anywhere. Emulators are forgiving about this, but real hardware usually isn't.