this is very likely a duplicate of the issue described in bug #585866, which
has now been fixed upstream with the auto-selection of the gpsd API version
at compile time.
direct connection to /dev/ttyS0 or ttyUSB0 only works with NMEA GPSs.
If yours has a SiRF chip or similar you'll have to put it into NMEA mode
first to get that ASCII protocol, not the new binary protocol. More hints
on how to do that at the gpsd website/help pages.
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