Re: [gpsd-users] gpsd loses the connection with the M8T when Raw is enabled.

[Stéphane Péneau]

Hi Gary!

A dead M9T?  Too bad!
I received a F9P and I finally hope to get my multiband antenna next week.

I switched the M8T refresh rate from 5 Hz to 1 Hz and I still have the 
checksum errors.

I will use an oscilloscope tomorrow.

Stéphane


Le 14/04/2019 à 01:29, Gary E. Miller a écrit :
> Yo Stéphane!
>
> On Sat, 13 Apr 2019 15:16:48 +0200
> Stéphane Péneau <address@hidden> wrote:
>
> > I use a Raspberry Pi 2, with Raspbian Stretch (4.14.98) and a U-blox
> > neo-M8T connected on the uart and the timepulse on the gpio18.
> Cool, I have similar here.  Except my M9T seems dead right now...
>
> > I need the nmea stream for a python script, and the raw stream to
> > postprocess the data with RTKLIB.
> OK.
>
> > When only nmea is enabled, everything is fine.
> Good.
>
> > But when I enabled UBX-RAWX and UBX-SFRBX, gpsd regularly loses the
> > connection and I don't receive any data for a few minutes.
> UBX-RAWX and UBX-SFRBX is a lot of data.
>
> Looks like your speed is 115,200, which may be a tad slow, or not:
>
>      gpsd:INFO: SER: speed 115200, 8N1
>
> You have a LOT of checksum errors:
>
> gpsd:IO: UBX checksum 0x6ef7 over length 61, expecting 0x0c25 (type 0x6201)
>
> That points to a serial port problem.
>
> I would put an oscilloscope on it and check the voltage levels of
> the serial lines, the voltage on the M8T, and that the serial line is
> not saturated.
>
> Also try a faster speed.
>
> You neglected to say how you started gpsd.  Be sure to use the -n option.
>
> > When I start gpsd with debug enabled, I see that it retry to connect
> > to the uart with a different speed and I don't understand why.
> Autobaud.  To stop autobaud, just set the port speed correctly before
> starting gpsd.  Or just let it do its job.  Which seems like it
> is working for you.
>
> > The full  log is attached with this mail
> Here is the interesting part:
>
>      gpsd:INFO: launching (Version 3.18.1)
>
> Please try git head.  There has been a lot of work for u-blox 8 and 9
> since then.  But I see nothing in your logs that git head might
> affect.  YMMV.
>
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
>         address@hidden  Tel:+1 541 382 8588
>
>             Veritas liberabit vos. -- Quid est veritas?
>      "If you can’t measure it, you can’t improve it." - Lord Kelvin