Re: [gpsd-dev] GPSd on FreeBSD

[O'Connor, Daniel]

> On 11 Sep 2019, at 06:03, Gary E. Miller <address@hidden> wrote:
>> I also see the MAGIC_HAT_ENABLE kludge - I ran sons like:
>> scons debug=true magic_hat=true
> 
> Yes, kudlge.  For one purpose; 1st time Raspberry Pi users that can't
> figure out how to use the command line.

That seems a little condescending and unhelpful to be honest.

> I'm not about to extend the kludge, I want to kill it off.  Just put
> "/dev/pps0" on your gpsd command line.

I tried that first, it doesn't work:
> If I run gpsd like so..
> sudo ./gpsd -D5 -NnG /dev/gps0 /dev/pps0
> I get..
> gpsd:PROG: selecting PPS driver...
> gpsd:PROG: PPS:/dev/pps0 chrony socket /var/run/chrony.pps0.sock doesn't exist
> gpsd:INFO: KPPS:/dev/pps0 RFC2783 path:/dev/pps0, fd is -2
> gpsd:INFO: KPPS:/dev/pps0 time_pps_create(-2) failed: Bad file descriptor
> gpsd:WARN: KPPS:/dev/pps0 kernel PPS unavailable, PPS accuracy will suffer
> gpsd:PROG: PPS:/dev/pps0 thread launched
> gpsd:INFO: PPS:/dev/pps0 ntpshm_link_activate: 0
> gpsd:INFO: device /dev/pps0 activated
> gpsd:PROG: KPPS:/dev/pps0 gps_fd:-2 not a tty, can not use TIOMCIWAIT
> gpsd:WARN: PPS:/dev/pps0 die: no TIOMCIWAIT, nor RFC2783 CANWAIT
> gpsd:PROG: PPS:/dev/pps0 gpsd_ppsmonitor exited.

/dev/gps0 points to /dev/cuau2
/dev/pp0 points to /dev/dmtpps0


>> gpsd:INFO: KPPS:/dev/pps0 kernel PPS timeout Operation timed out
>> 
>> So, closer but still not there.
> 
> A dead end.  On linux gpsd knows to create and check /dev/pps0.  That is
> the code path that needs to be fixed.  Or the code path from the command
> line.
> 
> I remember there was some commands to run before gpsd that fixed a simila9r
> issue on some gpsd's.  Someone needs to check the email archives.
> 
>> Full log at: http://www.dons.net.au/~darius/gpsd-2.log
> 
> No PPS at all in that log.  So not relevant to our PPS discussion.

There are plenty of messages about PPS, just that after init they all say:
gpsd:INFO: KPPS:/dev/pps0 kernel PPS timeout Operation timed out

If I put both /dev/cuau2 and /dev/dmtpps0 on the command line I see it get 
timeouts for cuau2 but work for dmtpps:
gpsd:PROG: KPPS:/dev/dmtpps assert  1568261257.999806732, sequence: 266942, 
clear   0.000000000, sequence: 0 - using: assert
gpsd:PROG: KPPS:/dev/dmtpps Assert cycle: 1568261257999806, duration:       0 @ 
 1568261257.999806732
gpsd:PROG: PPS:/dev/dmtpps Assert cycle: 1568261257999806, duration:       0 @  
1568261257.999806732
gpsd:PROG: PPS:/dev/dmtpps Assert ignored missing last_fixtime
gpsd:INFO: KPPS: pps_canwait 1

However after a little while it seems to give up on dmtpps (I guess because 
it's not producing any actual GPS messages):
gpsd:PROG: KPPS:/dev/dmtpps assert  1568261258.999806456, sequence: 266943, 
clear   0.000000000, sequence: 0 - using: assert
gpsd:PROG: KPPS:/dev/dmtpps Assert cycle:  999999, duration:       0 @  
1568261258.999806456
gpsd:PROG: PPS:/dev/dmtpps Assert cycle:  999999, duration:       0 @  
1568261258.999806456
gpsd:PROG: PPS:/dev/dmtpps Assert ignored missing last_fixtime
gpsd:PROG: KPPS:/dev/dmtpps descriptor cleaned up
gpsd:PROG: PPS:/dev/dmtpps gpsd_ppsmonitor exited.

So I guess that is why the kludge for the Pi Hat is there - to allow you to 
fuse the two devices into one.

--
Daniel O'Connor
"The nice thing about standards is that there
are so many of them to choose from."
 -- Andrew Tanenbaum