IP watchdog time out with ping. - old forum post


#1

kulminati

Joined on 09-05-2008
Posts 2
Kindly Help

Hi all,

I am VERY new to Opto 22 so please forgive me if my questions seem elementary. I recently have come across a problem that I could use some help with. We have opto 22’s in 2 different locations (Opto 22 SNAP-B3000-ENET). Basically the scenario is to use an IP Watchdog to ping an Opto 22 brain in Location A from Location B.

Now the goal is to use the IP Watchdog to keep pinging the brain, but in case loss of communication between the locations occurs, and the IP Watchdog can’t ping the brain in Loc A anymore, we want to trigger an event/reaction in an Opto 22 module in Loc B. So basically, as soon as the brain in Location A doesn’t respond, a module in Location B triggers a particular event/reaction to “safe” a system.

The modules are all digital btw.

How would I go about starting such a task? I could ANY help that you guys are willing to provide.

Thanks!

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09-11-2008, 7:54 AM

ben orchard

Joined on 12-08-2004
Posts 33
Re: Kindly Help

I suspect that this is very hard to do with just B3000-ENET’s.
It would be very simple to do with 2 controllers. (i.e swap the brains for PAC-R controllers?)
The brains only have event reactions in the way of automated responses, and can not be configured to have the other as remote I/O, so its hard to make them aware of the other brain.
Since you have the two brains, I suspect that you must have at least one controller in the mix somewhere (at location A, B or C)?
If this is the case, then you could use the controller to look at mem map address 0xF030 010C which is milliseconds since power-up on the two brains.
If you get two readings the same from the same brain, or it times out, then you have a problem and the controller can get the other brain to call for help, or the controller can do it.

If the ‘IP Watchdog’ you refer to is an external device and has a digital output that changes state when it can no longer ping the other brain, then you are in with a fighting chance.
(Its not clear from your description if you wanted the B3000-ENET to do the pinging).
If you have a digital input that changes state and you want an event reaction to take place, then start by reading from page 127 of document 1714.

A third way of doing what you want is to enable the watchdog on the brain and then set the digital states how you want them if it times out on communications.
This can be done from Pac Manager or Pac Control (IO Control).
This would be the quickest, but may not cover all your criteria as it will not specifically be pinging the other brain, just looking to see if it loses network connectivity itself.
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09-11-2008, 9:16 AM
kulminati

Joined on 09-05-2008
Posts 2
Re: Kindly Help

Thank you so much for your input! I will def look at Document 1714.

How can I go about configuring the watchdog on the brain? The goal would be to trigger the watchdog once the brain in Location B loses connectivity. So, as soon as the brain loses comm, the watchdog will trigger and the brain will then turn on an input module (which I will program to activate an output module). I’m just curious as to how would I go about setting the condition for the watchdog - and can this be done via ioManager?

Thanks once again !!

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09-12-2008, 1:57 PM

ben orchard

Joined on 12-08-2004
Posts 33
Re: Kindly Help

You will need to make sure you are running the current firmware version on the brains. (Check on the website under Support -> Downloads -> Firmware and compare it to what you see under ‘Status Read’ in IO Manager).
I would also download the current version of PAC Manager. (Also off the web site from the Downloads area).
Then, inspect your brain from PAC Manager.
Under the status write area you will see the Comm Watchdog Time (3rd description down).
This is the amount of time between losing communications and the watchdog getting set. Something like 1-5 seconds is reasonable.
Then, to set each digital output, go to the ‘Point Config’ area and select the digital module and the point you want to change on a time out.
You want to change the ‘Watchdog Output Value’. 0.000 = off and 1.000 = on.
Don’t forget to ‘Store configuration to flash’ in the Status Write area once you have it all set up the way you want, otherwise a power cycle will undo all your work.

It might be worth looking for the watchdog settings with the version of firmware and IO Manager that you have, you might get lucky and have it show up…


#2

For a related watchdog discussion, click here.