I though I would ask here before going down this rabbit hole. I have a system that is isolated and does not have any connections to the outside world and would like to sync the time between controllers so my event logs (created within the strategy) match. Does anyone have a simple way to do this by just using PAC Control? It doesn’t have to be down to the millisecond but should be close. The system has 2 Epic PR2’s and 7 R1’s.
One way we used to do this was our ‘master’ controller would generate a time stamp and write it out to the scratchpad. Every other controller would read the scratchpad and use it as the default.
I’ve had to do this for my home aircraft tracking setup.
I have about 8 computers, a SNAP controller and an EPIC that all needed to be time synced and could not rely on an Internet NTP server.
In my case (limited budget) I built a stratum 1 time server from a GPS receiver and Raspberry Pi.
Took about 30 minutes to install the software and get it running.
If you are not up for that, you could buy a stand alone NTP server, they start around $300 USD.
Once that is done and running on your network, the EPICs can point their time server config in groov Manage to that NTP server IP address. Don’t forget to set the time zone to match.
The SNAP Controllers will require you add a little code to a chart. You will find the help you need here: How to set the clock on a PAC Controller
I worked it out. It was pretty simple once I did it which was to just send the event to the master which is the Epic PR2 thru a string scratchpad. Each controller adds their event to a specific index and the master places the time stamp on it and adds it to a single event log. That way it doesn’t matter what the time is on the other controllers and works out well since I’m using the Groov HMI on the master.
Ah, I see now how I got off on the wrong foot…
I took this:
…to mean that the clocks on the controllers had to be close to real time, but not super accurate.
In actual fact, you don’t care if one controller is eight minutes fast and another is twelve minutes slow, also, there is no scheduling (ie, turning devices on or off at a set time), you just wanted to know when anything happened at any time.
@vmsMark Got you pointed in the right direction.
I had to do something very similar, a cruise ship going from one time zone to another during the trips, GPS was the solution.