I'd like to understand how RS232 works with ADA (Audio Design Associates) products, in particular the Cinema Rhapsody Mach IV-B.

Is it possible to achieve RS232 control using the ADA Bus port on the rear panel, and if so can this be two way control?

If two-way control can be done with the ADA Bus port, what is the purpose of ADA's ISO CAT II black box, which has a DB9 socket and is described as follows by ADA:

'The ISO-CAT-2 is designed to permit bi-directional ADA Bus to RS-232 communication. This is most frequently used when integrating RS-232 control systems (touch screen control systems) and/or PCs with ADA systems and components.'