Perspective, Recipe system (simple), part 1

I´m trying to build a simple Recipe system in Ignition (Maker)
I have createt Database/table in MariaDB (MySQL).
To move data from SQL to PLC I have made a Transaction Group
In the the Transaction Group I can not get the Write handshake (PV-status) to function the way I think it should work, it always write “OK”, both when the PLC orders a legal and a non-legal recipe. I think i have understod the Write handshake wrong, but I can not find a “good” desciption of this.
See above screendumps

The handshakes, I believe, are for things that keep the group itself from completing, usually in the Expression items. You’ll need to make a triggered item to handle when a recipe doesn’t exist.

The simplest would be a query with something like:
If the result is 0, that’s a no-recipe condition.

I think you need to reset the handshakes in the PLC for “next” time. Otherwise, it will stay high after the initial set.

Understood :wink: & thanks for answer

It make sense what you are writing, but I dont understand how I shall make this! I have done as the above screendump, is that the right way? Is still dont work?

You’re almost there! :slight_smile:

You can write that value back to PV_Status in the Target Name, instead of using the handshakes.

Succes :wink: Thank you

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