It should not be too difficult but depends on the model of PLC.
First off check you have a with IO licensed version of InTouch. You can check this by looking for an IO Server line in wwsuite.lic. If you have you can use a Wonderware driver, if not you will need to upgrade or buy Kepware or similar.
For Wonderware drivers there are a choice. I am not an expert in Omrom but I believe one of the Fins drivers should do what you want.
You will have to post PLC model and communications type (serial, Ethernet or other) if you want more help.