The Kramer VS-4228 is an 8 port matrix switcher for routing RS-422 control. It is designed to interconnect RS-422-controlled devices. The VS-4228 operates bi-directionally and offers automatic master/slave configuration. It sends control data from a master device to all destinations, and routes the response of the highest priority slave back to the master. There are a total of three ways to control VS-4228 - front panel buttons, RS-232, and RS-485. A large, bright LED display on the front panel shows the current status of the matrix, and the built-in memory stores and retrieves pre-set configurations.