C R McClenaghan
chris at mcclenaghan.com
Mon Jul 14 23:28:48 CEST 2008
Here are my results of pumping NMEA data from the FreeRunner to
another GPS client and pumping NMEA data from another GPS device to
FR -> GPSy (Mac OS X client) - could not get a fix on NMEA data
Garmin 10 -> FR - tangoGPS worked flawlessly
Apparently, agpsui reads directly from /dev/ttySAC1 even when gpsd is
running. Couldn't get agpsui to "see" the Garmin 10 data. Also, GPSy
worked flawlessly with Garmin 10 data.
As near as I can tell, the two data streams are very different in
terms of GPS data and information. I'm not knowledgeable enough to say
what the difference is, except the FR data is much more terse/brief
(shorter length of each line of data).
What this experiment tells me is that data coming from the FR GPS chip
either directly or via gpsd is does not contain enough information for
a fix. What software exists between gpsd and/or /dev/ttySAC, if any,
may be responsile or the GSP chip itself is not getting what it needs
from the antenna.
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