Automatic Rev counter update via sensor/switch

Hello,

We have an additional 7th axis on our IRB6650S. This axis is disconnected and reconnected as part of a routine. When disconnected, the resolver loses power and its stored absolute position.

We have a precise "home switch" that is triggered when the axis is in a specific, unique position. What function can be used to programmatically move the axis until it triggers the switch, and then update the rev counter based on that position? In other industries, this is sometimes referred to as "homing the system" or "reference move".

This is basically the same thing as when the operator would move the robot to "line up the arrows" to do a manual rev counter update, but it needs to be automatic. 

Thank you
Eric