# I/O Handler Script

Scripts can be added to assign host notification events that allow the Cognex Communication Card to report that an event was fired on the card.

The script can be a previously created script (with arguments that match, such as non-parameter scripts or scripts with two parameters, the first being an object and the second parameter being an EventArg or CogPrioEventArg), available in the User Script directory, or a new script can be added by pressing the plus button in the I/O Handler Script section.

Pressing the plus button will launch the New Script Name dialog, where the script must be given a name.

This will create a new User Script, which will automatically be assigned the parameters of the arguments exposed by the original host notification event, and the script will also be automatically selected as the host notification script. Press the ... button to open the selected script in the Script Editor.

When the project enters either Test Mode or Deployment Mode, the precision I/O events are enabled. You can disable the host notification event by selecting None in the I/O Handler Script drop-down.