PIC16F84A please help

After burning program into PIC chip. Upon power on, all portb bits output logic 1. which is correct as refered to the code below but the LED did not flicker. any idea on how the check wether XT clock pulse are supplied to PIC

org 0x00
bcf INTCON,GIE
bsf status,5
movlw 0x00
movwf 0x86
bcf status,5
goto loop

loop
movlw 0xFF
movwf 0x06
call delay
call delay1
movlw 0x00
movwf 0x06
call delay
call delay1
goto loop

delay
bcf status,z
movlw 0xFF
movwf 0x0F
return

delay1
decfsz 0x0F
goto delay1
return