Below is the board for the PFC Ap1000 , it control the yoke , rudder, throttle etc. I want to hook it up to simvim without completely rewiring everything (X-plane does not support Serial/rs232 devices ). i noticed the circuit design is basically the same as simvim except the Max231. it uses the sn74ls165n,sn74ls191n,sn74ls145n etc instead of CD74HC4067 as multiplexers . it also used tlc545ifn as ADC.
My question is can i just tap signal from the existing address bus(probably before the max231 chip) or i have to do everything from scratch.