Topics

Getting a Uputronics GPS Hat to work with Chrony?


Greg Engle
 

Anybody successful in getting this working to update the Pi clock?
Lots of information to set this up as a time server but I'm looking for a stand alone GPS for location and time for remote operation on WSJT-X.

It will show up with xgps, gpsmon and cgps -s
But I can't get it to update the clock in the PI

Ideas

Greg
NZ6E


MIKE RICHARDS
 
Edited

Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GPS

Regards,

Mike - G4WNC


 

The most accurate time, using Pulse Per Second or PPS, will use a GPS with PPS.  This is not something you achieve with a USB GPS.

The NW Digital Radio DRAWS™ HAT or Adafruit Ultimate GPS HAT are two examples of GPIO attached GPS with PPS.

On Mon, Oct 12, 2020 at 9:40 AM MIKE RICHARDS <mike@...> wrote:
Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GOPS

Regards,

Mike - G4WNC



--
John D. Hays
Kingston, WA
K7VE

 


Greg Engle
 

Mark,

 

I used your page for a puck GPS and it worked well once I figured out I had to use

/dev/serial/serial-by-id to identify it.

 

All the tools used to make sure it works, work but it’s not updating the time.

 

Greg NZ6E

 

From: RaspberryPi-4-HamRadio@groups.io <RaspberryPi-4-HamRadio@groups.io> On Behalf Of MIKE RICHARDS
Sent: Monday, October 12, 2020 9:38 AM
To: RaspberryPi-4-HamRadio@groups.io
Subject: Re: [RaspberryPi-4-HamRadio] Getting a Uputronics GPS Hat to work with Chrony?

 

[Edited Message Follows]

Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GPS

Regards,

Mike - G4WNC


Greg Engle
 

I should have added:

 

Without a network connection chronyc sources -v

Has the PPS0 and NEMA listed but with a ? and not recognized

 

From: RaspberryPi-4-HamRadio@groups.io <RaspberryPi-4-HamRadio@groups.io> On Behalf Of MIKE RICHARDS
Sent: Monday, October 12, 2020 9:38 AM
To: RaspberryPi-4-HamRadio@groups.io
Subject: Re: [RaspberryPi-4-HamRadio] Getting a Uputronics GPS Hat to work with Chrony?

 

[Edited Message Follows]

Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GPS

Regards,

Mike - G4WNC


David Ranch
 


Hello John,

From the table included in https://gpsd.gitlab.io/gpsd/gpsd-time-service-howto.html#_1pps_quality_issues , the bottom summary says that accuracy delta would only be say 100mS of a time delta.  I don't see how that could be a problem for 99.9% of most HAM use cases.  Maybe I'm missing something here?

--David
KI6ZHD




On 10/12/2020 09:47 AM, John D Hays - K7VE wrote:
The most accurate time, using Pulse Per Second or PPS, will use a GPS with PPS.  This is not something you achieve with a USB GPS.

The NW Digital Radio DRAWS™ HAT or Adafruit Ultimate GPS HAT are two examples of GPIO attached GPS with PPS.

On Mon, Oct 12, 2020 at 9:40 AM MIKE RICHARDS <mike@...> wrote:
Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GOPS

Regards,

Mike - G4WNC


--
John D. Hays
Kingston, WA
K7VE

 



 

Some just like a bit more precision -- here is a Raspberry Pi + Adafruit HAT

chronyc sources -v
210 Number of sources = 6

  .-- Source mode  '^' = server, '=' = peer, '#' = local clock.
 / .- Source state '*' = current synced, '+' = combined , '-' = not combined,
| /   '?' = unreachable, 'x' = time may be in error, '~' = time too variable.
||                                                 .- xxxx [ yyyy ] +/- zzzz
||      Reachability register (octal) -.           |  xxxx = adjusted offset,
||      Log2(Polling interval) --.      |          |  yyyy = measured offset,
||                                \     |          |  zzzz = estimated error.
||                                 |    |           \
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
#- GPS                           0   3   377    10    +28ms[  +28ms] +/-  111ms
#* PPS                           0   3   377    10   -193ns[  -65ns] +/-  205ns
^- 2001:49f0:d04c:1::2           2   9   377   490  -5846us[-5851us] +/-   41ms
^- 2001:470:e439:1::10           2  10   377   603   +706us[ +699us] +/-   54ms
^- x.ns.gin.ntt.net              2  10   377   605  -5024us[-5032us] +/-   38ms
^- srcf-ntp.stanford.edu         2  10   377   928    -11ms[  -11ms] +/-   56ms


On Mon, Oct 12, 2020 at 11:50 AM David Ranch <rpi4hamradio-groupsio@...> wrote:

Hello John,

From the table included in https://gpsd.gitlab.io/gpsd/gpsd-time-service-howto.html#_1pps_quality_issues , the bottom summary says that accuracy delta would only be say 100mS of a time delta.  I don't see how that could be a problem for 99.9% of most HAM use cases.  Maybe I'm missing something here?

--David
KI6ZHD




On 10/12/2020 09:47 AM, John D Hays - K7VE wrote:
The most accurate time, using Pulse Per Second or PPS, will use a GPS with PPS.  This is not something you achieve with a USB GPS.

The NW Digital Radio DRAWS™ HAT or Adafruit Ultimate GPS HAT are two examples of GPIO attached GPS with PPS.

On Mon, Oct 12, 2020 at 9:40 AM MIKE RICHARDS <mike@...> wrote:
Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GOPS

Regards,

Mike - G4WNC


--
John D. Hays
Kingston, WA
K7VE

 




--
John D. Hays
Kingston, WA
K7VE

 


Jason A. Powell
 

There's a mailing list for everyone:


I'll admit to being a bit obsessed with precise time myself. I recently built a Stratum-1 NTP server using the Adafruit Ultimate GPS hat: https://www.adafruit.com/product/2324.

Why? Because I could! :)

Jason
KD8FMR

On Mon, Oct 12, 2020 at 3:14 PM John D Hays - K7VE <john@...> wrote:
Some just like a bit more precision -- here is a Raspberry Pi + Adafruit HAT

chronyc sources -v
210 Number of sources = 6

  .-- Source mode  '^' = server, '=' = peer, '#' = local clock.
 / .- Source state '*' = current synced, '+' = combined , '-' = not combined,
| /   '?' = unreachable, 'x' = time may be in error, '~' = time too variable.
||                                                 .- xxxx [ yyyy ] +/- zzzz
||      Reachability register (octal) -.           |  xxxx = adjusted offset,
||      Log2(Polling interval) --.      |          |  yyyy = measured offset,
||                                \     |          |  zzzz = estimated error.
||                                 |    |           \
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
#- GPS                           0   3   377    10    +28ms[  +28ms] +/-  111ms
#* PPS                           0   3   377    10   -193ns[  -65ns] +/-  205ns
^- 2001:49f0:d04c:1::2           2   9   377   490  -5846us[-5851us] +/-   41ms
^- 2001:470:e439:1::10           2  10   377   603   +706us[ +699us] +/-   54ms
^- x.ns.gin.ntt.net              2  10   377   605  -5024us[-5032us] +/-   38ms
^- srcf-ntp.stanford.edu         2  10   377   928    -11ms[  -11ms] +/-   56ms


On Mon, Oct 12, 2020 at 11:50 AM David Ranch <rpi4hamradio-groupsio@...> wrote:

Hello John,

From the table included in https://gpsd.gitlab.io/gpsd/gpsd-time-service-howto.html#_1pps_quality_issues , the bottom summary says that accuracy delta would only be say 100mS of a time delta.  I don't see how that could be a problem for 99.9% of most HAM use cases.  Maybe I'm missing something here?

--David
KI6ZHD




On 10/12/2020 09:47 AM, John D Hays - K7VE wrote:
The most accurate time, using Pulse Per Second or PPS, will use a GPS with PPS.  This is not something you achieve with a USB GPS.

The NW Digital Radio DRAWS™ HAT or Adafruit Ultimate GPS HAT are two examples of GPIO attached GPS with PPS.

On Mon, Oct 12, 2020 at 9:40 AM MIKE RICHARDS <mike@...> wrote:
Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GOPS

Regards,

Mike - G4WNC


--
John D. Hays
Kingston, WA
K7VE

 




--
John D. Hays
Kingston, WA
K7VE

 


Greg Engle
 

Ok, how did you get there?

 

Mine is showing a ? in the source state.

 

From: RaspberryPi-4-HamRadio@groups.io <RaspberryPi-4-HamRadio@groups.io> On Behalf Of John D Hays - K7VE
Sent: Monday, October 12, 2020 12:11 PM
To: RaspberryPi-4-HamRadio@groups.io
Subject: Re: [RaspberryPi-4-HamRadio] Getting a Uputronics GPS Hat to work with Chrony?

 

Some just like a bit more precision -- here is a Raspberry Pi + Adafruit HAT

chronyc sources -v
210 Number of sources = 6

  .-- Source mode  '^' = server, '=' = peer, '#' = local clock.
 / .- Source state '*' = current synced, '+' = combined , '-' = not combined,
| /   '?' = unreachable, 'x' = time may be in error, '~' = time too variable.
||                                                 .- xxxx [ yyyy ] +/- zzzz
||      Reachability register (octal) -.           |  xxxx = adjusted offset,
||      Log2(Polling interval) --.      |          |  yyyy = measured offset,
||                                \     |          |  zzzz = estimated error.
||                                 |    |           \
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
#- GPS                           0   3   377    10    +28ms[  +28ms] +/-  111ms
#* PPS                           0   3   377    10   -193ns[  -65ns] +/-  205ns
^- 2001:49f0:d04c:1::2           2   9   377   490  -5846us[-5851us] +/-   41ms
^- 2001:470:e439:1::10           2  10   377   603   +706us[ +699us] +/-   54ms
^- x.ns.gin.ntt.net              2  10   377   605  -5024us[-5032us] +/-   38ms
^- srcf-ntp.stanford.edu         2  10   377   928    -11ms[  -11ms] +/-   56ms

 

On Mon, Oct 12, 2020 at 11:50 AM David Ranch <rpi4hamradio-groupsio@...> wrote:


Hello John,

From the table included in https://gpsd.gitlab.io/gpsd/gpsd-time-service-howto.html#_1pps_quality_issues , the bottom summary says that accuracy delta would only be say 100mS of a time delta.  I don't see how that could be a problem for 99.9% of most HAM use cases.  Maybe I'm missing something here?

--David
KI6ZHD



On 10/12/2020 09:47 AM, John D Hays - K7VE wrote:

The most accurate time, using Pulse Per Second or PPS, will use a GPS with PPS.  This is not something you achieve with a USB GPS.

The NW Digital Radio DRAWS™ HAT or Adafruit Ultimate GPS HAT are two examples of GPIO attached GPS with PPS.

 

On Mon, Oct 12, 2020 at 9:40 AM MIKE RICHARDS <mike@...> wrote:

Hi Greg,

I've written a tutorial that might help. Lots of people have used it successfully.

Chrony with Uputronics GOPS

Regards,

Mike - G4WNC


 

--

John D. Hays
Kingston, WA

K7VE

 

 

 

 


 

--

John D. Hays
Kingston, WA

K7VE

 

 

 


 

This is using an Adafruit Ultimate GPS Hat (similar for the DRAWS™)

Added to /boot/config.txt (again specific to the Adafruit Ultimate GPS Hat):
dtoverlay=pps-gpio,gpiopin=4


cat /etc/chrony/chrony.conf
# Welcome to the chrony configuration file. See chrony.conf(5) for more
# information about usuable directives.
refclock SHM 0 refid GPS precision 1e-3 offset 0.5 delay 0.2 poll 3 trust require
refclock SHM 2 refid PPS precision 1e-9 poll 3 trust
pool 2.debian.pool.ntp.org iburst

# This directive specify the location of the file containing ID/key pairs for
# NTP authentication.
keyfile /etc/chrony/chrony.keys

# This directive specify the file into which chronyd will store the rate
# information.
driftfile /var/lib/chrony/chrony.drift

# Uncomment the following line to turn logging on.
#log tracking measurements statistics

# Log files location.
logdir /var/log/chrony

# Stop bad estimates upsetting machine clock.
maxupdateskew 100.0

# This directive enables kernel synchronisation (every 11 minutes) of the
# real-time clock. Note that it can’t be used along with the 'rtcfile' directive.
rtcsync

# Step the system clock instead of slewing it if the adjustment is larger than
# one second, but only in the first three clock updates.
makestep 1 3

Add broadcast and allow stanzas as needed.

On Mon, Oct 12, 2020 at 1:54 PM Greg Engle <gfe@...> wrote:

Ok, how did you get there?

 

Mine is showing a ? in the source state.

 


--
John D. Hays
Kingston, WA
K7VE