Page 225 - Build Your Own Quadcopter_ Power Up Your Designs with the Parallax Elev-8

204 Bu il d Y o ur O w n Q u a d c o p t e r

Examples
4224.50 is 42 degrees and 24.50 minutes, or 24 minutes, 30 seconds. The “.50” of a minute
is exactly 30 seconds.
7045.80 is 70 degrees and 45.80 minutes, or 45 minutes, 48 seconds. The “.80” of a minute
is exactly 48 seconds.
Parsed GPS Message
The following is an example of a parsed GPGLL message that illustrates how to analyze an
actual data message:
$GPGLL,5133.80,N,14240.25,W*75
1 2 3 4 5 6 7
1 GP GPS NMEA designator
2 GLL Lat/Lon message type
3 5133.80 Current latitude 51 degrees, 33 minutes, 48 seconds
4 N North/South
5 14240.25 Current longitude 142 degrees, 40 minutes, 15 seconds
6 W East/West
7 *75 checksum

All GPS applications use some type of parser application to analyze data messages and
extract the required information to meet system requirements.

Propeller Mini

At this point I would like to take a moment to introduce you to the Propeller Mini module,
which I used as the onboard processor for the GPS receiver. The Propeller Mini, which I will
henceforth refer to as the Mini, is a relatively new Parallax module, just introduced in 2013.
The module is very reasonable in cost and fully supports the full Propeller Spin programming
language as well as any other Propeller-compatible language. Figure 8.13 is a picture of
the Mini.

Figure 8.13 Parallax Propeller Mini module.