We, at ABB corporate research (Switzerland), are currently working on a test automation project that uses OPC as the communication interface. I am planning to use OpenOPC for the OPC DA specification. However, the project also involves heavy usage of the OPC AE specification. Currently, OpenOPC has no support for OPC AE. I am thinking about extending OpenOPC to support OPC AE as well. While I have adequate programming experience, I am not very familiar with OPC specifications (the project started only a couple of months ago). Could someone be kind enough to outline the technical difficulties that I might face if I try to extend OpenOPC to include OPC AE. What, according to you then would be a reasonable time limit to complete this task? Also, if you could, point out what would be a good starting point.
OPC AE spec download and associated developer information -
What problems will you run into - well I can think of one off the top of my head -
for the same reason that "UpdateOnChange" doesn't work with OpenOPC, you're likely going to have a problem getting OpenOPC to 'accept' unsolicited data (whether it be alarm triggering or other) from the OPC Server.
A reasonable time to work around this or to just plain build it from scratch might be 3 to 5 months for prototype, and 1 year total for a tested working solution (given a small team of capable persons competent in both PLC programming and Python).