The Honeywell Enviracom Serial Adapter (Honeywell part # W8735A1005) is an RS-232 interface to the bus used by Honeywell communicating thermostats & assocated zoning system. See
According to the documentation, you can get/set most themostat parameters via a control program running on a PC, thru the serial adapter.
A sample "C" library is provided for mapping the command set & protocol, but the top-level code that reads / writes the serial port (via threads, as recommended) and calls a polling function on a per-second basis, is left as an exercise for the reader.
I'd be interested in hearing from anyone who has experience with this adapter, and who maybe even might have some code to share??
Thanks very much in advance!
Steve C in Seattle randomthinking A T hotmail.com