Servoing Windows System Time

[viSci]

I am trying to create a vi to servo the windows system time to match my cRIO clock which is disciplined by GPS.

I was hoping to find a IEEE1588 stack for windows that would do this for me but in the meantime...

It appears that the way to do this is by using a windows dll function called SetSystemTimeAdjustment which can speed up or slow down

the windows tick time, with this in hand, you can implement a PID servo loop to gradually sync the clock to an external reference.

I was wondering if anybody has gone down this path before and might have a few tips.

[jhoskins]

You could try using the command from the comand line of the PC/cRIO system you want to sysnc to.

net time \\ip address of the one you want to sync with / set

this is what we use to sync all our PC time together to one PC

[viSci]

The problem is that I do not have any master time servers on my network other than a GPS based IEEE1588 master clock node which is not supported by windows network time clients.

[Christian_L]

The problem is that I do not have any master time servers on my network other than a GPS based IEEE1588 master clock node which is not supported by windows network time clients.

You could build a simple SNTP server on your cRIO system and then have Windows sync to it using the built in NTP client. I haven't tried it, but I think it should work.

There's example code for a SNTP client on ni.com; you'd have to build the opposite end in this case.

[viSci]

Hi Christian,

Thanks for the suggestion. I took a look at the SNTP client vi's and they look pretty simple (as the name implies). I think I can get a SNTP server going

with this as a starting point. I hope that in a future release, NI will consider adding a 1588 windows client to the NI-SYNC driver.