PV 300 "Hearbeat" Monitor

Does anyone have any ideas on how to set up a "hearbeat" monitor for a PV300.

Here is what I have:
Contrologix processor communicating over serial link to PV300.
PV300 acts as a "remote" to control some things from up to 20 ft away.

What I want to do:
I want to monitor the status of the communication link from the processor to the PV300 and stop certain functions if the PV300 and the processor lose communication.

What I have tried:
I tried using the "message to remote" function in panel builder 32 but have some problems with it. I am using the notification tag and handshake tag to basically toggle a bit on and off via the PLC and processor. This sometime works and sometimes not, meaning that if it is up and running and I pull the cable out the notification bit stays on and is never cleared since the handshake from the PLC is never received. Also, when I cannot get this functionality to resume if I pull the comm cable and then later plug it back in. As far as I can tell PV300 doesn't support macros and the only way to set a bit is by actually pressing a button on the PV300... did I miss something?

Anyone have any ideas on another way to accomplish this?

Thanks in advance...

An entirely different approach might be to GSV the channel 0 comms status in the PLC. I have never done this but I'm sure there's something available. (In a SLC or Micro, i just use the Ch0 Comms Active bit for stuff like that.)

Paul C

How about simply reading the the One Second "Status Tag". If you set the update time to 1 second you should be able to test for a change in the value at least every 2 seconds.