I'm tired to google .. what is the time controller used in modern smartphones and what is its benchmark of time? In what form does this controller present information to the installed operating system?

  • phones can take time from the network, from GPS and from the internal clock. - Mikhail Vaysman

2 answers 2

The smartphone has a quartz resonator and a microcircuit counter. The accuracy of the built-in quartz is quite acceptable for the average user, especially if the phone is new. Over time, due to the "fatigue" of the crystal, the frequency begins to "go away" and the clock lies more and more. Thus, the built-in quartz is the standard of time for a smartphone offline.

It is clear that quartz has a much lower accuracy than atomic standards, so in the online mode, the smartphone synchronizes its internal clock with external standards of time. Typically, NTP is used — when connected to the Internet, a smartphone contacts the time servers and synchronizes with them. More advanced models for synchronization can use GPS / GLONASS or GSM network signals.

  • It should be added that for synchronization via GPS, the Internet is not needed, but via GSM - only a SIM card is needed, and it’s somewhat doubtful about the models' advancement - as long as I remember myself in the android settings, there was always the "Get time / time zone from the network" option. times from GSM tower - pavlofff
  • So the algorithm is as follows: there is a memory in the microcircuit which, by default, has a date of 1970, when we turn it on we set the time, then the microcircuit counts the time and says so much in nanoseconds from 1970. From time to time it is synchronized with the exact number of nanoseconds from 1970. Well, this is for Unix systems such a countdown in nanoseconds from 1970. Well, the question remains, what is the standard of the seconds in a quartz resonator? Well, I think that now I can google - Turalllb
  • @pavlofff As far as I know, this is not just GSM, but NTP. However, maybe I am mistaken. - user194374
  • @kff this setting puts the time and without access to the Internet, and with recent experiments with time zones, on the MTS I have had half an hour’s time for the difference between the network and the real one, and on the megaphone the correct one. - pavlofff

Apparently, the RTC has long been built, and is powered by a common battery. OS after startup gets the current time by NTP.

  • I think not from a common battery, because when it is removed, the clock continues to work. Only in very budget phones, time has to be put on a new one. OS I think so quickly is not synchronized by NTP. Well, that's not the point. - Turalllb