Honeywell's Data Port Expander provides additional RS422 ports for the
connection of keyboards and Protocol Interface Translators (PITs). This
capability greatly enhances the ease of installation of the system – now devices
can have “home run” wiring, directly connecting keyboards and PITs to the RS422
Simple “pin to pin” wiring using 9-pin, male-tomale connectors eliminates
cable confusion, cutting installation labor and reducing costs.
The data port expanders are also repeaters – extending the distance of RS422
communications beyond the standard 4,000 feet. Multiple data port expanders can
be cascaded to form longer cable lengths.