So I'm hooked up to a sparkfun GPS over a serial port, and I'm able to read the NMEA output just fine- I get the GGA and VTG sentences at 1Hz.
My issue comes in at trying to send commands to the GPS, any set commands invariably result in the invalid command sentence being sent, for example the serial port configuration example in the manual:
$PTNLSPT,04800,8,N,1,4,4*11
results in
$PTNLRPT,V*2A
Furthermore, some query sentences work and some do not- for example, I'm able to query the almanac status, but issuing the query command for version info spits out an invalid command sentence.
Is there something I'm missing with sparkfun's copernicus gps or NMEA?