4000 SX  (250-4900)                Pinouts              Faxback Doc. # 1525 

   RS-232c serial port      Pin Assignments:                               
                                1. Carrier Detect                          
                                2. Receive Data                           
                                3. Transmittal Data                       
                                4. Data Terminal Ready                   
                                5. Signal Ground  
                                6. Data Set Ready 
                                7. Request To Send                      
                                8. Clear To Send                       
                                9. Ring Indicator                     
    Parallel I/O printer port (25-pin connector on peripheral bd.)    
                                                                      
      Pin Assignments:                                               
                        1. strobe                                      
                        2. Data Bit 0                                   
                        3. Data Bit 1                                  
                        4. Data Bit 2                                  
                        5. Data Bit 3                                  
                        6. Data Bit 4                                 
                        7. Data Bit 5                                 
                        8. Data Bit 6                                 
                        9. Data Bit 7                                 
                        10. ACKNOWLEDGE                                
                        11. BUSY                                       
                        12. PAPER END                                      
                        13. SELECT                                         
                        14. AUTO FEED                                     
                        15. ERROR                                         
                        16. INITIALIZE                                     
                        17. SELECT IN                               
                        18. 25-Ground                              

                        CONNECTOR PIN-OUTS                                 

   Video Port Connector Pinout                                             
                                                                          
   Pin          Function                                                  
                                                                           
   1            Red Video                                                  
   2            Green Video                                                
   3            Blue Video                                                 
   4            Monitor ID Bit 2 (not used)                                
   5            Ground                                                     
   6            Red Return (ground)                                        
   7            Green Return (ground)                                      
   8            Blue Return (ground)                                       
   9            Key (no pin)                                               
   10           Sync Return (ground)                                       
   11           Monitor ID Bit 0 (not used)                                
   12           Monitor ID Bit 1 (not used)                                
   13           Horizontal Sync                                            
   14           Vertical Sync                
   15           Not Used                     

   Monochrome-type monitors use Green Video for all video input            
   and ignore Red Video and Blue Video.  Monitor ID Bits are not used in   
   the VGA. Monitor type is determined when your system is turned on.      
                                                                           
 VIDEO FEATURE EDGE CONNECTOR PINOUT                                       
                                                                           
   Pin          Function  (front component side of the adapter)            
                                                                           
   Y1           C0 (color bit 0)                                           
   Y2           C1 (color bit 1)                                           
   Y3           C2 (color bit 2)                                           
   Y4           C3 (color bit 3)                                           
   Y5           C4 (color bit 4)                                           
   Y6           C5 (color bit 5)                                          
   Y7           C6 (color bit 6)                                          
   Y8           C7 (color bit 7)                                           
   Y9           DAC Clock                                                  
   Y10          DAC Blanking                                               
   Y11          Ext. Horizontal Sync                                       
   Y12          Ext. Vertical Sync                                 
   Y13          Ground                                             

   VIDEO FEATURE EDGE CONNECTOR PINOUT                                     
   (back side of the board)                                                
                                                                           
   Z1           Ground                                                     
   Z2           Ground                                                     
   Z3           Ground                                                     
   Z4           Select Internal Video                                      
   Z5           Select Internal Syncs                                      
   Z6           Select Internal DAC                                        
   Z7           Not Used                                                   
   Z8           Ground                                                     
   Z9           Ground                                                     
   Z10          Ground                                                     
   Z11          Ground                                                     
   Z12          Not Used                                                   
   Z13          Not Used