MARVINS MAZE
                                                      CN4      
 ---------                    --------                ---------
B1   GND                      A1   GND                 1  +5V
B2                            A2   COIN                2  +5V
B3   1 START                  A3   SVC                 3  GND
B4                            A4   2 START             4  GND
B5                            A5                       5  ---
B6   GND                      A6   GND                 6  +12V          
B7   1 DOWN                   A7   1 UP
B8   1 RIGHT                  A8   1 LEFT              CN5
B9   1 PUSH 2                 A9   1 FIRE              --------
B10                           A10                       1  +5V
B11                           A11                       2  +5V
B12  2 DOWN                   A12  2 UP                 3  GND
B13  2 RIGHT                  A13  2 LEFT               4  GND
B14  2 PUSH 2                 A14  2 FIRE               5  ---
B15                           A15                       6  ---
B16  VID BL                   A16  SYNC
B17  VID RED                  A17  VID GN
B18  GND                      A18
B19  SP+                      A19  SP-
B20                           A20