The connections are broken out in two ways. The connections on the left of the board are setup to mate to a DB-9 female or to the right with a 6 pin mini wafer connector. Since I will be using the RS-232 pins I decided to just use the DB-9 side. All the connection I need are on the top of the board so I used a .100 inch header soldered to the top of the board to break out the pins:
2 - RS-232 out
3 - RS-232 in
4 - Power
5 - Ground
Pin 1 is marked on the board as X1. I powered the board with 5 volts and connected my USB to RS-232 adapter to it and was able to see the serial NMEA sentences at 4800 baud on pin 2.
Just for fun I wanted to see the accuracy of this GPS module and had I found an interesting piece of freeware called VisualGPS. The software is designed to take the NMEA data from the GPS for a period of time while it is stationary and produce an analysis of the variations. The following is the analysis after about 12 hours.
It is interesting to see the variance over time. The GPS system is very complex and many calculations are made, both in the GPS module and in the system as a whole via the ground stations and uplinked via the satellite messaging.
The NMEA strings contain position information of the satellites which VisualGPS can also plot:
As well as a coverage plot:
The longer you collect data the more complete the plot will become. This can be useful for evaluating the antenna and the orientation of the antenna.
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