Download Strategy to SNAP PAC R1 Controller

Hi everyone, I am writing this since I am completely new to OPTO22 hardware and software
and my question may be very simple but I have doubts on how to download my strategy
into the controller I am using.
This is the scenario: I have a laptop where I have the strategy, I need to download to the controller, can I use an Ethernet cable to connect directly and use the loopback IP address of the controller to communicate with it?
Now, what are steps I need to take in order to download properly?

Thanks for your help

If you have configured an IP address (not the loopback address) in your controller and configured your computer to be on the same subnet as the controller, an ethernet cable will do the trick. Beyond that, make sure you configured the controller’s IP address in the control engine you have selected for your strategy, and the strategy will download when you click Debug. Opto22’s documentation on the controller walks you through the steps in pretty good detail, suggest you start with the docs for your controller and go from there Almost all the documentation you need will already be installed on your system when you installed PAC Project, just go to Help/Manuals/Browse other PAC Project manuals.

Hi JesusGlobal,
Welcome to the forums! There’s an exception to what rcobourn mentions above: If you are using PAC Sim (our PAC Simulator) running on the same PC as your PAC Control software, then you would use the loopback address ( to communicate with it. But since you mentioned an Ethernet cable, I’m guessing you have a “real” controller? Have you assigned an IP address to that controller using PAC Manager?

Thank you very much for the iformation given, Yes I have a real controller SNAP PAC R1, I am using 4 SNAP ODC5R Digital outputs
and one analog output SNAP AIV-i.
I want to download the strategy from my laptop to the controller, using an ethernet cable directly. I am not going to connect the controller to the network, just want to run it by itself, Do I still need to configure the IP address? how about the digital and analog modules?

Yes! In order to communicate with a controller, it will need to have an IP address on the same network/subnet as the PC which will talk to it. You can configure your modules from within the strategy (they’ll be in the “I/O Units” folder, under a particular I/O Unit – that will probably have the IP loopback since your controller & I/O Unit are at the same IP address in the case of an R1).

Sounds like you should come to our FREE! training here in Temecula, California. There’s also a “self training” guide link at the top of that page.

Do you know the IP address of your PC? Is your Ethernet cable a standard cable or crossover cable? Don’t forget our Product Support is Free! and they are always happy to help, too.

I’m also curious: Why do you want to “just want to run it by itself” and not on the network? (Often putting a controller on the network is easier than getting your PC and cabling set up to communicate directly to the controller.)


I wish I could go to the training, but it is not possible. I have been in contact with Mr. Tom Edwards but for some reason he has not reply to my last 2 e-mails.
I do not know the IP address of the PC. The IT person told me that the server usually assigns a different IP address every time the PC is boot in the network.
I will be using a standard Ethernet cable. The controller will only be running the program to control a fixture which is used to inser rivets.
It will control the product being traveling through the fixture and will verify presence of the rivets as well as the force of insertion. So it is not needed to put the controller in the network.
I am not sure if I explained myself well, what I want to to is to connect to the controller debug and download the program so that the controller can run it. I understand I need to configure the IP address on the controller and the I/O modules but that is what I can not get quite yet, sorry for bothering but as I mentioned this is the first time I work with this hardware and software and actually the first time I am programming a PLC.

Go ahead and program the controller with an IP address on a private network not in use at your facility, something like, then temporarily change the IP address of the computer to, and you should be able to ping the controller, and download a strategy to it. Don’t forget to set the computer back to DHCP when you are done.

If the computer was made in the last few years, you probably won’t need a crossover cable as modern ethernet ports are auto-sensing.

One trick I’ve picked up is to have a USB to Ethernet adapter handy. When I connect it to my laptop, it always gets the custom IP address I have assigned to it, and I don’t have to mess with the settings of my primary ethernet port, or disconnect from the office network when working there. This works best if you assign all your controllers to a network like 192.168.x.y (where perhaps x represents location and y a device number), and use a netmask of

This information is great, now, let me try to get it my way. I have a PC that I need to connect to the network in order to have an IP address.
I am not sure that I can get a private network, so I will not count on that. Now, I need a crossover cable to connect to the controller
my question is where do I connect the crossover cable in the PC? if the ethernet port is already taken?
I really do not know what a crossover cable is and how it is connected.

Rcobourn: Good idea, I really liked this one.

JesusGlobal. With respect, I really would suggest some basic IT network training before going much further and exploring Opto22. While Opto22 kit is easy to use and implement, it still needs some base knowledge that you do not have yet. There are a number of self help training books around. If you try to implement an automation or control project at the moment you are just going to get annoyed with everybody and everything including the Opto22 equipment, which is a shame as its actually the best and most user friendly solution on the market.

…Just saying.

Thank you very much for everything, all this info is just great and I am really learning a lot I appreciate everybodies input. I know
I am completely new to all this, but there is no money to get any trainig and I am in a compressed time to get this done.
and this is the reason I am looking for a faster way to finish this. If I would have the time and money to get training I would not be asking dumb questions.
So again, this is the reason for me to look for input with people who are experts in the field.
Thank you very much for your help it was really great.

For what it is worth, you can probably disconnect the existing ethernet cable from the wall and plug it into your controller. You can set the IP address you want in the computer. If you don’t get a link light on the controller, you need a crossover cable or just grab a network switch and install it between the computer and controller.

I understand the feeling of not having time for the training, but I would suggest that the couple days you spend at the (free!) training could save you many more days of pounding your head against the wall.

Good luck!


I know you are in a hurry, but you sure can save a lot of time by checking out Opto22 FREE self paced training guides. You can do them as fast or as slow as you wish. A great place to start is

And if you don’t have any time at all, then check out Opto22’s fantastic “OptoMinute” videos, available on YouTube and Apple Podcasts

At exactly 60 seconds, I don’t think you could get more compressed basic training! Some of the points you mention are covered. And if you don’t understand the videos in English, most are also available in Spanish and Chinese.

I think you are not valuing your time properly. The time you waste by not getting some basic training or even following some self training program before starting an automation project, directly equates to hours, money and unnecessary project delays, which is even more money. I think you should explain this to your boss. If you are self employed you have to explain it to yourself.


Gmitchell: I agree 100% with you. Training and basic knowledge makes everything much easier. As of today I am progressing with the project and just having few difficulties, I hope to get through these today.

I really appreciate all your help.