Les Nagy’s information related to connecting to the GPS 315.

There are four contact pads on the back of the case which are used for
external power and data connections. The cable connects to the back with
a screw in the same manner as the battery door. These contacts are
always exposed to the environment, even while the cable is connected, so
there could be problems with dirt breaking contact during use. The
contacts have the following functions:  

                       O                    O
                      V+                    GND



               O                                    O
            Data In                             Data Out

If more than 2 volts is applied to V+, the unit switches over to
external power. The cigarette power cord supplies 3.6 volts, so this
should not be exceeded if Magellan's power cord is not used. The data
out pad supplies a 0 to 6 volt logic signal, but I have not tested the
requirements of the data in pad.

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
    Les Nagy    info@atsi.on.ca
Aldebaran Technological Services Inc.
Phone: 905-388-1011
Fax     : 905-388-9028
http://www.atsi.on.ca