Re: [gpsd-users] Problem with gpsd blocking device while it doesn't send NMEA messages

[B.W. Guffey]

On Fri, 2017-07-07 at 11:13 -0400, Larry Boyd wrote:
> The problem is that that unit needs you to send a start command to it
> to turn it on and start it up.
> You can either use wvdial like this;
> http://www.tjansson.dk/2009/01/using-the-builtin-gps-in-a-thinkpad-x2
> 00-under-linux/
> 
> Or you can use gpsd device-hook like this;
> http://forums.fedoraforum.org/showthread.php?t=290251

I went through the the F5521GW nightmare on a Toughbook running
openSuse.

The card has two serial ports: /dev/ACM1 (Device Management) and
/dev/ACM2 (GPS).  You have to send the right commands to the right
port.  The fedora forum post works but you have to follow it to the
letter.

These are the commands device-hook needs to send...

AT*E2GPSCNT=1,5,1 (Enables the GPS, send it to the DM port)
AT*E2GPSNPD (Starts the NMEA stream, send it to the GPS port)
AT*E2GPSCNT=0,0,0 (Disables the GPS and stops NMEA, send it to the DM
port)

To be honest though, after weeks of toiling and final getting it to
communicate with gpsd reliably, I found it's GPS functionality to be
complete crap...  Horrible reception, sometimes it took an hour to get
a first fix even with an external antenna on the roof of my house.  It
would inexplicably lock up at other times, likely conflicting with the
WWAN somehow.  Since I didn't give a flip about it's WWAN capabilities
anyway I ended up replacing the module with a U-BLOX card (drop-in
replacement) and all was right with the world.