Re: [gpsd-dev] ✘cgps

[Gary E. Miller]

Yo Fred!

On Fri, 1 Apr 2016 16:00:18 -0700 (PDT)
Fred Wright <address@hidden> wrote:

> On Thu, 31 Mar 2016, Gary E. Miller wrote:
> > On Thu, 31 Mar 2016 18:58:34 -0700 (PDT)
> > Fred Wright <address@hidden> wrote:  
> 
> > > Actually, I just tried it again and it didn't choke (and
> > > setti=led on the generic NMEA driver), so I'm not sure what was
> > > going on when I tried it before, but this receiver is finicky
> > > enough about antenna placement when running indoors that it's not
> > > the best choice for most testing, anyway.  
> 
> I happened to want to try this receiver again for another reason, and
> I think I now see what the trouble is, and it has nothing to do with
> the data.  When pointing GPSD at the Bluetooth serial device on the
> Mac, it usually (but not always) thinks (based on the log messages)
> that it's supposed to be a PPS source (even though the doc claims
> that there are rather specific naming requirements for a PPS
> device).  Sanitizing it by passing the data through nc and pointing
> GPSD at the TCP port gets around it.

Odd, if you can send me a trace "gpsd -nND 8 /dev/ttyXXX" I can get
that fixed.

> That's the opposite of the problem I have on my time server
> (BeagleBone Black running Debian stable), where GPSD refuses to
> recognize my actual PPS source (direct GPIO from the GPS cape).

It can't, you need to tell gpsd where to find the PPS since there is
no standard mapping from the UART to the GPIO pins.

Similar issue on the RasPi.  Documented in the install file.

> > I have found another issue.  I have some USB cables that corrupt
> > the data.  Happened to me yesterday and confused me for hours.
> > Swapping the cable and my problems went away.  
> 
> There's probably some bad software conspiring with the bad cable to
> make undetected errors that common, though the USB integrity checking
> is pretty lame.  It's been pointed out that you shouldn't use USB to
> copy an entire disk drive because the chance of an undetected error
> is too high.

I, and many others, have complained that the Linux USB driver tolerance
of bad hardware is very poor.  Things are better without S.  As long
as the USB driver does not crash I have very good luck copying TB over
USB.

RGDS
GARY
---------------------------------------------------------------------------
Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        address@hidden  Tel:+1 541 382 8588

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