The RTE has 4 optically coupled and isolated auxiliary outputs labeled K1 thru K4. These may be controlled by customized buttons in rig control software such as HR Deluxe and many others.  They operate from a 19,200 or 9600bps command set.

RTE-232. Aux outputs are on the lower terminal strip

K1 output: Output K1 is activated when CI-V or RS-232 data is detected. This is intended to be used to turn on and off the station when access is requested. Simply attempt to access your radio via a rig control program such as HR Deluxe and this output will activate. Activation can be used to control a relay that switches AC or DC power to your radio. If, for some reason you lose Ethernet connection, this output deactivates after 30 seconds of inactivity.

You may use this feature for fail-safe operation or to merely provide a convenient method of station power control.

For example, units such as Lowell's RPC-1 can be directly connected to the K1 terminals. Or simply build one yourself by wiring up a relay inside an outlet box. When you access your radio, the AC power will be applied and the radio will turn on and connect to HRD. It will turn off 30 seconds after you shut down HRD.

K2 output: Output K2 is intended for PTT control. When activated via a rig control button command, it will "close". This closure can directly key a radio PTT line. If, for some reason due to a communication failure, this line will open after a 3 minute time-out. Like a repeater timeout feature, this will automatically reset when the lockup is cleared. 

The K2 PTT feature and the 3 minute timer keeps you completely legal

K3 and K4 outputs: These are independent outputs that can be used to switch antennas or to remotely reboot computers. Wiring the isolated output of K3 or K4 directly to the panel power switch of most computers will control the turn-on/off function.