Thank you, but I have already fixed the error.
;i:cx=base
;o:dx=number
;m:ax,bx,dx
inumber:
xor dx,dx
mov bx,1
mov ah,1
inum:
int 021
cmp al,0d
je crfound
push ax
call inum
pop ax
xor ah,ah
sub al,030
push dx
mul bx
pop dx
add dx,ax
push dx
mov ax,bx
mul cx
mov bx,ax
pop dx
crfound:
ret