On the PLC side I’ve got an array of structures.
Each structure has the fields Day, Number, ID, ProductCode.
I tried to use a Dataset to load it at once; not only is it a convenient way to handle the structure, but it also seem to allow for handling its size on the PLC side without the need for tweaking it also on Ignition tag’s configuration.
I defined an UDT (“MachineScheduling”) because I have also other fields that I need to group together. It contains my “Data” Tag, whose type is “Dataset”.
I preloaded 5 rows in the PLC with random data.
When I connect the tag by providing OPC Path, the value gets loaded into my “Data” tag; as you can see in the next picture the dataset succeds in loading all the 5 rows as separate dataset rows.
But if you look at the root “value”, you see that it reads “Dataset [5R x 1C]”; That is: 1C = 1 column!!!
The columns of the dataset are not recognized and split; what I get is a single column with all my struct data inside.
You can confirm that by looking the values objects: i’ve got one for row and it’s not further subdivided into cell-values.
I haven’t tried to use an array-of-array structure on PLC side yet, because that would be less convenient as it would loose the field names.
Is this latter solution the only way Datasets are expected to work? Or is there an error in my configuration?
Thanks in advance