DT_Elapsed timer, how to compensate for inaccuracy over long periods ?

[BrianS]

I'll try that. I don't have a manual way to sync the PC's clock to a time server as it is locked out and is updated by a local server. So, I don't know exactly when it's clock is updated to a time server. I try to find a better way to compare the time to.

Thanks,
Bryan

[Charles Linquis]

If you really want accurate timekeeping, you can set up an interrupt on zero-crossings of the AC power line.
Or - If you are brave, I can send you a portion of a program I wrote that contacts NTP time servers (requires a Lantronix XPort or similar) and PBPL.
Or - if you are outdoors, you can get time from a GPS module.

[BrianS]

If you really want accurate timekeeping, you can set up an interrupt on zero-crossings of the AC power line.
Or - If you are brave, I can send you a portion of a program I wrote that contacts NTP time servers (requires a Lantronix XPort or similar) and PBPL.
Or - if you are outdoors, you can get time from a GPS module.

Thanks,
Turns out it was the PC clock was updated by the time server during the period I was monitoring the timer. Found that the timer code/circuit keeps very accurate time for my needs.

Bryan