MOV TMOD, #50H				
SETB TR1					
       
MOV DPL, #LOW(LEDcodes)		
      								
       
MOV DPH, #HIGH(LEDcodes)	
       
CLR P3.4					
CLR P3.3					
      again:
CALL setDirection			
MOV A, TL1					
CJNE A, #10, skip			
CALL clearTimer				
      skip:
MOVC A, @A+DPTR				
      								 
      								
      								 
      								
       
MOV C, F0					
       
MOV ACC.7, C				 
      								
       
MOV P1, A					
      								
       
JMP again					
       
      setDirection:
PUSH ACC					
       
PUSH 20H					 
      								
       
CLR A						
MOV 20H, #0					
MOV C, P2.0					
MOV ACC.0, C				
MOV C, F0					
MOV 0, C					
       
CJNE A, 20H, changeDir		
      								
       
JMP finish					
      changeDir:
CLR P3.0					
CLR P3.1					
       
CALL clearTimer				
MOV C, P2.0					
MOV F0, C					
MOV P3.0, C					
CPL C						
       
MOV P3.1, C					
      								 
      								
      finish:
POP 20H						
POP ACC						
RET							
       
      clearTimer:
CLR A						
CLR TR1						
MOV TL1, #0					
SETB TR1					
RET							
       
LEDcodes:		 
      				
DB 11000000B, 11111001B, 10100100B, 10110000B, 10011001B, 10010010B, 10000010B, 11111000B, 10000000B, 10010000B