PIP can be recalibrated from the keyboard while it is being charged. This may be useful to correct for wear or different operating surfaces. This should not normally be necessary but it may help in certain very specialised situations. If you think you need to change PIP's calibration, contact Swallow Systems for our leaflet "changing PIP's calibration" document number XPIP 010. Calibration changes can only be made when PIP is on charge and the correct password has been entered.