Checking Gateway Logs for Tag/OPC Writes

Hello all,

Hopefully this is an easy one. In the Gateway logs, is there a way to see a history of ignition’s Tag/OPC writes? We have a particular address in a PLC that we are writing a nonzero value to. However, when we write the value to the address it first assumes a value of zero before taking on the value we are writing. I don’t believe this is an ignition issue, but would like to be able to prove it with some logs.

Any tips? Are there certain filters I should use, for example? We are using the latest release of Ignition.

Are you writing from scripting? If so, which write function, system.opc or system.tag?


I’m using a mixture of system.tag and system.opc in different areas. The “0 flash” in question is occurring on a call to system.tag.writeAll(paths,values).

I also tried system.tag.writeSynchronous individually for the two tags in the path/values lists, but the same issue persisted.

I don’t mind switching to OPC writes if necessary, if those are more loggable.


Any updates on this? We continue to have some PLC registers dropping to 0 immediately prior to taking on their new values. We’ve worked around it for now, but it would still be helpful to rule out ignition as the culprit!