#INCLUDE "P16F628A.INC" 
 __CONFIG _XT_OSC&_PWRT_ON&_MCRLE_OFF&_BODEN_OFF&_WD_OFF
         CBLOCK 0x30
         T1
         T2
         ENDC
         ORG      0
         GOTO     START

        
START    CLRF    PORTA
         MOVLW   H'07'
         MOVWF   CMCON
         BCF     STATUS,RP1
         BSF     STATUS,RP0

         MOVLW    B'11110000'
         MOVWF    TRISA 
         MOVLW    B'00000000' 
         MOVWF    TRISB 
         BCF      STATUS,RP0
       
         MOVLW    B'00000001'
         MOVWF    PORTA

VISSZA:  MOVLW    B'10000000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'01000000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00100000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00010000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00001000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000100' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000010' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000001' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000001' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000010' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000100' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00001000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00010000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00100000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'01000000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'10000000' 
         MOVWF    PORTB 
         CALL     DELAY 
         MOVLW    B'00000000' 
         MOVWF    PORTB 
         CALL     DELAY 
         GOTO     VISSZA 

DELAY:   MOVLW    d'150' 
         MOVWF    T1
DEL:     MOVLW    d'255' 
         MOVWF    T2
DEL1:    NOP 
         NOP 
         NOP 
         NOP 
         NOP 
         NOP 
         NOP 
         NOP 
         DECFSZ   T2,f
         GOTO     DEL1 
         DECFSZ   T1,f
         GOTO     DEL 
         RETURN 
         END