Ok... Here is my code... What is in comment works if uncommented and if the line below is commented. But if I program the following code, my P3.4 Led doesn't flash at all. Is it because I set low the P3.7 and P3.6??? I suppose. But if I can't set them to 0 (unless I want to use their special function), how do I use them as programmable output?

Thanks.

PS: Sorry for the name, it's my nickname since my first name is really Julius.

Code:
-----

org 0h
ajmp start

org 100h
start:
;SETB 0B4h
MOV 0Bh,0FFh ;This doesn't make my LED blink
ACALL tempo
;CLR 0B4h
CLR 0Bh ;This doesn't make my LED blink
ACALL tempo
AJMP start

tempo:
MOV A,#0FFh
tempo1:
DEC A
JNZ tempo2
RET
tempo2:
MOV R1,#0FFh
tempo3:
DEC R1
JNZ tempo3
AJMP tempo1

END