Anybus produce transaction update mode - trigger byte vs cyclic

Hello, I am using a AB7318 Ethernet/IP to CAN anybus module with AB Controllogix PLC. Anybus is setup as a generic ethernet module.

I setup a produce transaction in the anybus module using Communicator CAN. The transaction consists of a total of two bytes, first byte is a fixed constant, second byte is a variable data mapped to the PLC. If I setup the update mode of the transaction to Trigger Byte and populate the data byte and toggle the trigger byte from the PLC the transaction works as expected. If I change the update mode to Cyclic/500ms and update the data byte from the PLC the transaction will execute every 500ms but the data byte will always be zero, regardless of what the PLC is writing.

Is this expected behavior?


Hello @es1,

Every 500ms it should be outputting the data in that memory location. Are you clearing that data after you write it once? Is there any change if you keep rewriting the data?


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Found the issue. I wasn’t updating the mapped bytes. It works as expected now. Thanks for the response.