2 replies to this topic

[ZakieM]

I was trying to see how accuracte the time is on the Netduino Plus, so took code of NTP and made the Netduino be updated from the network, then do almost nothing but Thread.Sleep and waited for 10 hours to check again DateTime.Now compared to the NTP and found the difference to be 6 seconds behind. This means that over a day we should expect 14-15 seconds lag. The test was made in ~25C environment. Is this reasonable? Is the best way to compensate on that is probe the NTP server once in few hours instead?

[Mario Vernari]

The crystal of the Netduino has a typical accuracy of 100ppm. 6 seconds out of 36000 (10h) is about 170ppm. So the accuracy couldn't be much better than this. However, I think there could be some firmware issue related to the time management (e.g. some interrupt is lost, etc) Cheers

[ZakieM]

Thanks Mario. So basically we see about 70% more in ppm that we should, which means there are firmware issues. With the number of times I need to pull the USB out and in again because deploying or start debugging gets stuck, it is of no surprise that there "could be" firmware issues. I will test this with FEZ Panda II that I got at home to see if works better or not.