PC to CPU:
  
  'STX' 'ADR' 'O' 'CHK' 'ETX'
      'O'
      
  	  
  	  ASCII-Code 0x4F OR 0X80 = 0xCF
 	    
    
    Example:
    
  	
    ADR = 1
 	  
   
    String =
     
  	
    0x02 0x81 0xCF 0xCE 0x03 (5 Bytes)
 	  
   
 CPU to PC
  
  'STX' 'ADR' 'O' Dig0 Dig1 Dig2 Dig3 … Dign 'CHK' 'ETX' (read value)
      'O'
      
  	  
  	  ASCII-Code 0x4F OR 0X80 = 0xCF
 	    
    The length of the answer of the CPU depends on the configuration of the unit. All available digital channels are returned. The coordination is evident out of the index of the service expression.
      Dig0
      
  	  
  	  = unused
 	    
    
      Dig1
      
  	  
  	  = unused
 	    
    
       Dig2
      
  	  
  	   = unused
 	    
    
      Dig3
      
  	  
  	   = digital channel with index 1 (3)
 	    
    
      Dig4 
      
  	  
  	    = digital channel with index 2 (4)
 	    
    
       Dig5
      
  	  
  	  = digital channel with index 3 (5)
 	    
    
       Dig6
      
  	  
  	  = digital channel with index 4 (6)
 	    
    
      Dig7
      
  	  
  	  = digital channel with index 5 (7)
 	    
    
      Dig8
      
  	  
  	  = digital channel with index 6 (8)
 	    
    
       Dig9
      
  	  
  	   = digital channel with index 7 (9) 
 	    
    
      Dig10
      
  	  
  	   = digital channel with index 8 (10)
 	    
    
       Dig11
      
  	  
  	   = digital channel with index 9 (11)
 	    
    
       Dig12
      
  	  
  	    = digital channel with index 10 (12)
 	    
    
      Dig13
      
  	  
  	   = digital channel with index 11 (13)
 	    
    
      Dig14
      
  	  
  	    = digital channel with index 12 (14)
 	    
    
      Example:
      
  	  
  	    ADR = 1
 	    
    
      String =
      
  	  
  	    0x02 0x81 0xCF 0xB0 0xB1 0xB0 0xB1 0xB1 0xB0 0xB1 0xB1 0xB1 0xB0 0xB0 0xB1 0xB1 0xB0 0xB1 0xFE 0x03 (20 Bytes)
 	    
     
                                                             
                                                             
          