In a project where you have HAI for the full home automatiuon and BitWise Control for the handheld remote control, how do you control the audio system as the RS-232 port on the audio system is being used by the HAI controller?

The easy way to do this is to connect an RS-232 cable from the HTX/BC4X1 to a spare RS-232 port on the HAI controller. You can then send commands into the HAI controller to make it do what ever you want. You can specify the text strings that will be used in Messages from within PC Access and write automation blocks to perform the task you want. i.e. switch source 1 to zone 1 etc. Alternatively if you look at the triggers in automation block programming you will see a trigger called HAI Triggers. There are 127 of them. They are listed as HAI1, HAI2 etc. These get triggered if the text string "HAI1", "HAI2", etc is received on any RS-232 port. This saves you using up all your messages. Again automation block programming can be used to to make these triggers actually do something. This is the easiest way to have control of the audio or anything under the HAI controller from a BitWise Control project.

For the cable that connects the two I would recommend buying the serial cable 36A05-4 which gives you a flat cable with an RJ11 at each end. Then buy an RJ34 back to back coupler (AS-U-C5E-INC-1) and a patch lead. Cut the plug off the end of the patch lead and strip back the wires to go into the screw down terminals on the HTX/BC4X1. If you trace the wires through this cable you will find that the wires are as follows:-
Green - Ground
Blue - TX
Green/White - RX

You will need to make sure you put the Blue TX wire into the RX connection on the HTX/BC4X1 and the Green/White RX wire into the TX connection on the HTX/BC4X1 to make it work.