from Anonymous on 12/07/2014
Its a standard HP41 surveying module see HP41C.org for functionality. Does the main surveying points and traversing, etc.
Obviously display is minimal due to the calculator's display footprint, but is easy to input and output is ok and can be printed out to the thermal printer or saved as a file.
Very importantly, if you don't have the manual see hp41.org and download the manual which gives the module inputs, outputs and type of calculations supported will become clear.