INT 21h does not print

Question

I wonder why this procedure does not print:

print:
push ax
push bx
push dx
mov ah, 02h      

ciclo:
mov al, [si]   
int 21h
inc si
loop ciclo

pop dx
pop bx
pop         


        

Answer 1

It will print the character in DL (see this reference).

For example, if DL contains the decimal value 65, it will print the character A (since 65 is the ASCII code for 'A')