GPSD users, developers, et alia:

Instead of addressing each response I received thus far, I decided to
aggregate my responses into a comprehensive discourse of what I tried
to ascertain regarding the state of my system from a hardware and
software perspective.

Well my friend Mark did send me this link already:
https://gpsd.gitlab.io/gpsd/gpsd-time-service-howto.html

Follows hereupon an enumeration of tests and measurements I conducted
on my GD8200 running Debian Linux (Trixie) predicated upon the some
several replies I received and my own research into how to detect or
test my laptop's internal GPS receiver and any ostensibly existing PPS
capabilities and their being enabled.

Whilst I am happy to gain more insights from everyone on this list, I
believe (based on test number 7) that my GPS likely does not have PPS
capability for some reason. I do not have an oscilloscope and won't be
making such tests. I would be happy just getting the time from the GPS
(even if slightly less accurate) so that I can have the proper system
time even when I stand absent connectivity to the internet (to use the
USNO NTP servers).

Nothing I do on my laptop is transaction based that requires precise
time down to the millisecond or microsecond level. If the time is
within 10 seconds of the most accurate time, fine for me. The idea of
such might make some people on this list sick to their stomachs, but
for me it is sufficient.

One of the links presented here was sent to me by my friend Mark and I
had begun reviewing at work on Friday during my lunch.

I appreciate most greatly everyone's input and thoughts on the matters
before you in the instant case.

1) Checking gpsd for PPS support

$ gpsd -h | grep -i pps
PPS device, or a URL in one of the following forms:
                PPS
# KPPS enabled.

2) Checking the kernel for PPS support

/proc/config did not exist, but I used this trick to ostensibly
ascertain the same information:

$ cat /boot/config-6.12.48+deb13-amd64  | grep -i pps
CONFIG_PPS=y
# CONFIG_PPS_DEBUG is not set
# PPS clients support
# CONFIG_PPS_CLIENT_KTIMER is not set
CONFIG_PPS_CLIENT_LDISC=m
CONFIG_PPS_CLIENT_PARPORT=m
# CONFIG_PPS_CLIENT_GPIO is not set
# PPS generators support

$ lsmod | grep -i pps
pps_ldisc              16384  1

3) Using gpspipe to determine if PPS sentences or information is
present over a 10 minute sample time.

$ timeout 600s gpspipe -wP > /tmp/gpspipe

$ cat /tmp/gpspipe | grep -i pps
{"class":"WATCH","enable":true,"json":true,"nmea":false,"raw":0,"scaled":false,"timing":false,"split24":false,"pps":true}

4) Execution of ntpshmmon over a 10 minute sample time

$ timeout 600s sudo ntpshmmon
ntpshmmon: version 3.25
#      Name  Seen@                 Clock                 Real         
       L Prc
sample NTP0  1761959885.903232834  1761952151.613393400 
1761952151.570000000 0  -1

5) Consulting the GD8200 documentation

Succeeding a review and inspection of the GD8200 user manual, it
stands demonstrative of a very basic amount of information regarding
the GPS option for the laptop. However, it is conspicuously absent any
discussion concerning the PPS capability whatsoever. I was also unable
to locate a copy of any service manual or any other technical manuals
beyond the user manual.

6) Checking for device definition in /dev/

$ ls -la /dev/pps*
crw------- 1 root root 248, 0 Oct 31 16:09 /dev/pps0

7) Used ppswatch to conduct a test over a 60 second sample time

$ timeout 60s sudo ppswatch -a /dev/pps0
trying PPS source "/dev/pps0"
found PPS source "/dev/pps0"
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)
time_pps_fetch() error -1 (Connection timed out)

Total number of PPS signals: 0
Maximum divergence: 0
Mean value: 0
Standard deviation: -nan

$
 Very Respectfully,

Stuart Blake Tener, BScCS, N3GWG (Extra), MROP
Computer Scientist / FCC Licensed Radio Operator

Las Vegas, NV / Philadelphia, PA

+(1) 310.358.0202 Mobile Phone / WhatsApp
+(1) 215.338.6005 Google Voice

Amateur Radio IDs: DMR: 3132252[nn], 3132499 and NXDN ID: 6627

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