Is it possiple to select presets already defined in the P4800 by use of the RS232 (or 422) bus from a computer which is not also interfacing the P4800 in setup mode? The application is command-line control from the PC of a pre-configured P4800 which will not otherwise be changed by the end user.
This is only possible if you want to write your own software program that will spit out RS232 commands to the P4800. The RS232 commands can be found at:
P4800 RS232 Codes - AMX / Crestron Subprograms