Nixie Clock DA-2000 Operating Instructions Manual

Nixie Clock DA-2000 Operating Instructions Manual Manual pdf 28 page image

Time HandlingTime provider prioritiesThe clock has three time providers:• NTP time provider• RTC time provider• Internal time providerThe clock will always try to use the time provider furthest up the list, because each time youdrop down to a lower priority time provider, features are lost.Each time a time provider is updated, it updates the lower priority providers. That means thateach time an NTP update is received, the RTC and internal providers are also updated.NTP time providerThe NTP time provider has the advantage that it is always synchronised to a network atmoictime source. The maximum deviation from truly correct time is about 1 second, and will neverdrift more than this. Each time an update is made, the clock corrects itself to the true time.The NTP time provider also understands Daylight Savings time, and will automatically correctitself to Daylight savings time changes on the next update.The NTP time provider also restores the time on clock startup and therefore is able to show thecorrect time, even after the clock has been turned off.RTC time providerThe RTC time provider is fairly accurate, but is not as highly accurate as the NTP time provider.It will drift over time, and is not able to track Daylight Savings Time changes.The RTC time provder does however remember the time if you turn off the clock, and will startagain with a correct time if you have fitted a battery.Note: Unfortunately we are not allowed to ship batteries for the battery backup. You will haveto locate a battery if you want the RTC time provider to track time while the clock is turned off.The correct battery is:CR1220Internal time providerThe internal time provider is not very accurate, and will drift significantly over time. It does notremember the time while turned off. This is a “last resort” time provider, and should normallynot be used.Page 28