Welcome, Guest
Username: Password: Remember me
20 Aug 2017
INDI development team is happy to announce the release of INDI Library v1.5.0. This new exciting release builds on the maturity of INDI Library and comes with many new supported devices and fixes for existing drivers.
Read More...
  • Page:
  • 1

TOPIC: Tight time sync between devices?

Tight time sync between devices? 9 months 1 day ago #14749

  • Platone
  • Platone's Avatar Topic Author
  • Offline
  • Senior Boarder
  • Senior Boarder
  • Posts: 44
  • Thank you received: 12
Hi all,
Does yet exist some work on tight time synchronization between remote servers/client? I need less than one ms synchronization between two mounts w/ cameras placed on different places and connected from a remote client.

Thanks in advance,
Ilia.

Please Log in or Create an account to join the conversation.

If something has worked, it will work again.

Tight time sync between devices? 9 months 21 hours ago #14751

This is not entirely clear. Perhaps elaborate more. You want two remote mount drivers to have same time when they start up? If that's the case, then both need to have a GPS module to sync to with that accuracy.
The following user(s) said Thank You: Platone

Please Log in or Create an account to join the conversation.

Jasem Mutlaq
Support INDI & Ekos; Get StellarMate Astrophotography Gadget.
How to Submit Logs when you have problems?

Tight time sync between devices? 9 months 19 hours ago #14754

... or both of them need to run NTP server.
The following user(s) said Thank You: Platone

Please Log in or Create an account to join the conversation.

Tight time sync between devices? 9 months 18 hours ago #14755

  • Platone
  • Platone's Avatar Topic Author
  • Offline
  • Senior Boarder
  • Senior Boarder
  • Posts: 44
  • Thank you received: 12
Thanks for the replies.

An NTP server is a good idea, but it's not as much precise (PTP is its evolution in this manner). I need a method for precise timestamping of Camera/Telescope events like slew/Capture, scheduling captures for example. PTP (which could be implemented into a raspberry and a GPS) or something similar is like that I was looking for. For example a Ping-style word for hard-locking the client with the servers. Can this be done using the INDI protocol?
My goal is to build a new type of interferometer. It's basically simple as concept and needs synchronizing the capture mounts/cameras.

Please Log in or Create an account to join the conversation.

If something has worked, it will work again.
Last Edit: by Platone.

Tight time sync between devices? 9 months 10 hours ago #14760

As the matter of fact you can use NTP and GPS to retrieve PPS signal, which get you to nanosecond precision.
I have been using such a setup on my Raspberry Pi for a while. The latest kernel does support kernel-mode PPS so you don't need to recompile. Depending on your distro you might need to recompile NTP server due to some releases are compiled without shared memory PPS support.
Take a look at this link to set it up.

BTW. I believe precise time synchronization should be provided by OS (kernel level) and not INDI. It is hardly possible to manage it outside of kernel space due to inherent delays related to system resource management in the user space.
The following user(s) said Thank You: Platone

Please Log in or Create an account to join the conversation.

Last Edit: by Kaczorek.

Tight time sync between devices? 9 months 9 hours ago #14761

  • Platone
  • Platone's Avatar Topic Author
  • Offline
  • Senior Boarder
  • Senior Boarder
  • Posts: 44
  • Thank you received: 12
Thank you very much!

I'll check this link, I've seen a similar system in past (one month ago ..).
This is exacly what I was searching for, but I forgot it! My memory's got corrupted XD

Please Log in or Create an account to join the conversation.

If something has worked, it will work again.
  • Page:
  • 1
Time to create page: 0.086 seconds

Login



3rd Party

Choose from the numerous 3rd party INDI drivers to suit your needs!

Got Problem?

Check out the FAQ, the forum, and the bug tracking system to resolve any issues you might have!
You can also subscribe to INDI newsletter and development mailing lists to get the latest updates on INDI!


Gallery

Replica

Why INDI

Replica