The default operation mode of NiceLabel Automation is asynchronous mode. Asynchronous mode is a form of printing, during which a trigger sends data for printing and closes connection with the print subsystem. The trigger does not wait for the result of the printing process and does not receive any feedback. Immediately after the data is sent, the trigger is ready to accept a new incoming data stream.
Asynchronous mode boosts trigger performance and increases the number of triggers that can be processed in a time frame. Each printing process has buffer in front – this is where the trigger feeds the print requests in. The buffer accommodates for trigger spikes and makes sure no data is lost.
If an error occurs during processing, it still gets logged in Automation Manager (and NiceLabel Control Center, if you use it), but the trigger by itself is not aware of it. When running Automation in asynchronous print mode, you cannot define conditional actions that would execute, if the trigger execution is in error.
In comparison to asynchronous mode, synchronous mode doesn't break connection when the printing process begins. In this mode, the trigger sends data for printing and keeps the connection to the print subsystem established for as long as it is busy executing actions. When the printing process is complete (successfully or with an error), the trigger receives feedback about the status.
You can use this information inside the actions that are defined in the same trigger and decide to execute another action in case an error occurs. You can also send print job status back to the data-issuing application. For more information, see section Print Job Status Feedback.