I have 27 Reference Positions that trigger Digital Outputs(memory). These same positions are contained in Position Registers as well. We use these to indicate to a PC running Labview of where the robot is. We also need to be able to command the robot to go to these positions via PCDK and through the teach pendant manually - in which case it is easiest to use the position register.
The problem is when we re-teach a position register, we also need to remember to update the Reference Position to match it. The positions will change often as we have different products to interface with.