Re: [gpsd-dev] Detecting Raspberry Pi Hat & PPS

[Frank]

On May 5, 2016, at 9:37 PM, Gary E. Miller <address@hidden> wrote:

Per Oliver's suggestion, I have just pushed to git head a new log message.

I just did a fresh git clone (8:30AM EST).  Recompiled & the first run, gpsd sees PPS:

gpsd -nND 9 /dev/ttyAMA0 |& fgrep PPS
gpsd:PROG: PPS:/dev/ttyAMA0 chrony socket /var/run/chrony.ttyAMA0.sock doesn't exist
gpsd:INFO: KPPS:/dev/pps0 RFC2783 path:/dev/pps0, fd is 7
gpsd:INFO: KPPS:/dev/pps0 pps_caps 0x1151
gpsd:INFO: KPPS:/dev/pps0 have PPS_CANWAIT
gpsd:WARN: KPPS:/dev/pps0 missing PPS_CAPTURECLEAR, pulse may be offset
gpsd:INFO: KPPS:/dev/pps0 kernel PPS will be used
gpsd:PROG: PPS:/dev/pps0 thread launched
gpsd:INFO: PPS:/dev/ttyAMA0 ntpshm_link_activate: 1
gpsd:INFO: KPPS:/dev/pps0 kernel PPS timeout Interrupted system call
gpsd:INFO: KPPS:/dev/pps0 kernel PPS timeout Interrupted system call
gpsd:INFO: KPPS:/dev/pps0 kernel PPS timeout Interrupted system call
gpsd:PROG: KPPS:/dev/pps0 assert  1462537682.901482605, sequence: 53362, clear   0.000000000, sequence: 0 - using: assert
gpsd:PROG: KPPS:/dev/pps0 Assert cycle: 1462537682901482, duration:       0 @  1462537682.901482605
gpsd:RAW: PPS:/dev/pps0 Assert pps-detect changed to 1
gpsd:PROG: PPS:/dev/pps0 Assert cycle: 1462537682901482, duration:       0 @  1462537682.901482605
gpsd:PROG: PPS:/dev/pps0 Assert rejected missing last_fixtime
gpsd:PROG: KPPS:/dev/pps0 assert  1462537683.901488646, sequence: 53363, clear   0.000000000, sequence: 0 - using: assert
gpsd:PROG: KPPS:/dev/pps0 Assert cycle: 1000006, duration:       0 @  1462537683.901488646
gpsd:RAW: PPS:/dev/pps0 Assert pps-detect invisible pulse

However… 

It consistently works when starting with:  gpsd -nND 9 /dev/ttyAMA0

I’ve narrowed it down to if it’s started *without* “-n”, then there’s never any attempt to even look at PPS (no PPS debug entries) & cgps/gpsmon do not see PPS

I haven’t looked at the code.  Are the Pi specific changes only triggered only with “-n”, if the device is queried at gaps startup?

Checking for C header file sys/timepps.h… yes

Note that the troubleshooting before today (May 6th), gpsd was built before the “timepps.h” file was on my system.  I built gpsd on May 2nd.  I emerged pps-tools on May 5th.

-rw-r--r-- 1 root root 5908 May  5 14:48 /usr/include/sys/timepps.h