PROJ3205 I/O board Analysis. 

VMEBus Decodes at C00000 And C04000.

C00000 Triggers INT0 or P3.2 on the 8031. 
C04000 Triggers INT1 or P3.3 On the 8031. 

A Write at These addresses puts D0 - D7 onto PortA of U16-SA8155