Kramer Electronics RC-78R - Manual (Page 11)

8 RC-76R/RC-78R - Connecting the RC-76R/RC-78R
Figure 2: Connecting the RC-76R/RC-78R Room Controllers
4.1 Connecting RS-232 Devices
You can control up to two AV devices such as a projector or an RS-232 display by
connecting them to the RC-76R/RC-78R via their RS-232 connection.
To connect a device to the RC-76R/RC-78R via RS-232:

Using a straight cable, connect pin 2 to TX, pin 3 to RX and pin 5 to GND on
the RS-232 terminal block connector of the RC-76R/RC-78R
4.2 Connecting RS-485 Devices
You can control up to one AV device by connecting it to the RC-76R/RC-78R via
its RS-485 connection.
To connect a device to the RC-76R/RC-78R via RS-485: