list p=16F84A
 #include <p16F84A.inc>
 __CONFIG _CP_OFF & _WDT_OFF & _PWRTE_ON & _XT_OSC
PORTB     EQU  0x0006
TRISB     EQU  0x0086 ;
STATUS    EQU 0x0003 ;
PORTA     EQU  0x0005  ;
TRISA     EQU  0x0085 ;
OPTION_REG  EQU 0x0081 ;
AA        EQU   0x000C
BB        EQU  0x000D
CC        EQU   0Eh
SPEED     EQU   0Fh
WSTOR     EQU   10h
STORSTATUS EQU  11h

#DEFINE   BANK1    BSF STATUS,05
#DEFINE   BANK0    BCF  STATUS,05
 


org       00H
          GOTO   STAR

ORG       04H

          
         
STAR
          BANK1
          BCF     OPTION_REG,7 
          MOVLW   b'11111111'
          MOVWF   TRISB
          MOVLW   b'11111110'
          MOVWF   TRISA
          BANK0
BOUCLE   
;;;;;;;;;;
          BSF     PORTA,0 ;
          CALL    T1ms;
          CALL    T1ms;
          CALL    T1ms;
;;;;;;;;;;
          BCF     PORTA,0    
          CALL    T1ms ;    

          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;;

          BTFSS   PORTB,0 ;
          BSF     PORTA,0;
          BTFSC   PORTB,0
          BCF     PORTA,0
          CALL    T1ms;
;;;;;;;;;;
          BCF     PORTA,0    
          CALL    T1ms ;    

          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;;
          BTFSS   PORTB,1 ;
          BSF     PORTA,0;
          BTFSC   PORTB,1
          BCF     PORTA,0
          CALL    T1ms;
   
;;;;;;;;;; 
          BCF     PORTA,0    
          CALL    T1ms ;    
;;
          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;;
          BTFSS   PORTB,2 ;
          BSF     PORTA,0;
          BTFSC   PORTB,2
          BCF     PORTA,0
          CALL    T1ms;
;;;;;;;;;; 
          BCF     PORTA,0    
          CALL    T1ms ;    
;;
          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;;
          BTFSS   PORTB,3 ;
          BSF     PORTA,0;
          BTFSC   PORTB,3
          BCF     PORTA,0
          CALL    T1ms;
;;;;;;;;;; 
          BCF     PORTA,0    
          CALL    T1ms ;    
;;
          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;; 
          BTFSS   PORTB,0 ;
          BSF     PORTA,0;
          BTFSC   PORTB,0
          BCF     PORTA,0
          CALL    T1ms;
;;;;;;;;;;
          BCF     PORTA,0    
          CALL    T1ms ;    
;;
          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;;
          BTFSS   PORTB,1 ;
          BSF     PORTA,0;
          BTFSC   PORTB,1
          BCF     PORTA,0
          CALL    T1ms;
   
;;;;;;;;;; 
          BCF     PORTA,0    
          CALL    T1ms ;    
;;
          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;;
          BTFSS   PORTB,2 ;
          BSF     PORTA,0;
          BTFSC   PORTB,2
          BCF     PORTA,0
          CALL    T1ms;
;;;;;;;;;; 
          BCF     PORTA,0    
          CALL    T1ms ;    
;;
          BSF     PORTA,0 ;
          CALL    T1ms;
;;;;;;;;;;
          BTFSS   PORTB,3 ;
          BSF     PORTA,0;
          BTFSC   PORTB,3
          BCF     PORTA,0
          CALL    T1ms;
;;;;;;;;;; 
          BCF     PORTA,0
          CALL    T1ms;
          CALL    T1ms;
          CALL    T1ms;
          GOTO    BOUCLE
;******************************************************************************************

T1ms
          MOVLW  0xf9
          MOVWF  AA
LOOP1
          NOP 
          DECFSZ AA
          GOTO   LOOP1


RETURN 
T20MS
          MOVLW  0x14
          MOVWF  BB
LOOP3
          CALL T1ms
          DECFSZ  BB
          GOTO  LOOP3
RETURN
 


end