Chartbook Companion CDs include "Offshore Navigator Lite" GPS positioning software. Offshore Navigator Lite's GPS features include:

Connect a USB GPS to your PC to see your position right on the chart.  As you move the vessel icon moves.

Or, connect an industry-standard NMEA 0183 GPS receiver to your PC.
View GPS Compatibility List

Data Windows display key GPS data such as Lat/Lon, COG, and SOG. They also instantly calculate course information such as Cross-Track Error and Range and Bearing to the next waypoint.

Transfer waypoints directly from your PC into popular GPS receivers. Say goodbye to the task of keying waypoints in one by one. View GPS Compatibility List