OptoDatalink Issue

Hello everybody.

I am new to the forum, and I have a question regarding an Issue I am experiencing with Optodatalink.

First I need to give you an input regarding the application.

We have some test bench 5 of them to be more precise. The benches test different products from the production line. All tests are performed with an OPTO22 controller with its respective I/O units and connected via Network to a computer running Optodatalink.

I have a problem with Datalink hanging or not reporting properly.

This is the thing, optodatalink is polling a flag every second, when the flag goes up it means the data is ready to be reported, optodatalink pulls the information, and writes it to a MySQL database.

when the test is finisihed, the software on PAC raises the flag datalink reads the information (a series of fields containing test information) and report it to a database. Every bench test 24 products at a time, so it takes almot 40 seconds to write an entire batch.

The thing is that we have 5 benches testing simultaneosly, and chances that all of them start raising flags and reporting at the same time is really high. We changed polling time for each bench, I mean some of them poll every 0.5 seconds, the other every second, the other every 1.5 seconds and so.

But once the benches start reporting the report 24 times, different varibales for each product, so if all of them start reporting at the same time it would be 120 different register, with 15 information fields art intervals of 1 second and I am not sure datalink is designed to handle that.

I understand Datalink can scan variables, just not sure it can be done so quick and wich such volumes of information, hence it hangs from time to time I am also guessing it hangs when several test benches coincide in reporting at the same time.

If you need more info regarding the application i can expand it just ask.

I just hope you guys can help me or give me some more direction.

Best regards.


We just found another unexplainable issue.

The machine in the other warehouse seems to be stopping all links after a weekend. Every monday, machine must be rebooted in order for datalink to work.

We checked this morning and we saw thar all links were stopped. Every monday we have the same behaviour. Is datalink windows 2003 server compatible?

Hello Mino,
Welcome to the OptoForums. Although I’d be interested in hearing if others have suggestions for you here on the OptoForums, you might want to contact our PSG (product support group) with troubleshooting help for this. http://www.opto22.com/site/support.aspx
It’s FREE!

Ok I will try.

Gudday Mino,

As well as saying ‘yeah, what Mary said’ (about taking to our Product Support Group), I also want to bounce this idea off you…

Check out http://internetio.com (Accept the security certificate when you get the warning, I coded that site myself and so its a self signed cert. No big deal… You can trust me right? Right?)

On the ‘Concepts’ page I offer some OptoScript and PHP that will allow you to insert data from a controller to MySQL via PHP. In other words, no OptoDataLink needed.
We have had that script and database collecting data every second for the past 2 and a bit years and since its all on a UPS, we have had zero downtime. Not a single skipped record insert.

If you have access to both your strategy and you dont mind the download… and if you have a PC that you can run the PHP on (in our case, its the same PC as MySQL is running on (a Linux PC)), then its really worth a look at I think.

The one bit of PHP is all that is needed for all 5 of your controllers. You will not need to space them out in time as you can hit the PHP with a 100 or more connections with no trouble.
As you know the MySQL will also take a bizillion (technical term there) connections and inserts with no trouble (unless your running it on a RaspberryPi, but I doubt it).

Anyway, I have not used OptoDataLink that much. I taught that section in our monthly class back when we covered that… have not touched it since, so I cant help trouble shoot it or offer stress testing results…
The controller->PHP->MySQL on the other hand, I have been messing with for years. Just set it up on a controller 2 weeks ago in fact, its now collecting data every half second, and has not missed a beat (I get an email if it errors).

Food for thought.



Woaa… that sounds really interesting… I myself know PHP and it gets interesting…

Thank you so much… I will check it and post comments as things go.

I am trying to access the information on http://internetio.com but it looks like the certificate is expired. Is it possible to create a new certificate so I can have a look?


-Update- Never mind, the problem is on my end.

Thanks again.

Hi Jfarmer,

Welcome to the forums!

I just had a look at the site and the certificate and its still working great.
Its a self signed cert, so the expiry matters not.
Yes, it expired back in February, that said, the logs show me that around 700 people have accepted the certificate since then and have no problems.
Simply accept it and you should be in and running.

Have you been to the site before? Im wondering if its your browser thats knocking it back?

Lets know how you go…


I have been working with the Opto22 support group to resolve some issues. A new version of Datalink, actually a new version of PAC Project has just been released that resolves these issues. They may even resolve yours.

I have about 13 links between 4 R2 units and several access databases. I did find one bug where if I had a problem with one of the access databases, all the links shut down, not just the problem link. I recommend bringing up you database, one by one if you have several. You may find that one of them has an error. Letting access correct it may help.