Ericsson SPR1100, Handbook, Page: 224 / 256

Home > SPR1100 Handbook > Appendices > Clock and Timing > Real Time Clock
Real Time Clock
Overview
The Host Controller card has a real time clock, which is battery powered when the chassis is
unpowered, so that the time and date is maintained. This clock is designed to be accurate to
±1 minute per month. The battery is capable of powering the clock for over two years.
User Configurable Parameters
The user configurable parameters associated with the clock are defined below
Parameter Values Description
Local Time hh:mm:ss Current local time in hours
minutes and seconds
Local Date dd:mm:yyyy Current date in day month
and year
SNTP Server
An SNTP server can be configured to update the clock and calendar or else the user can
update the time and date. Any changes to the time and date are recorded in the system log.
The real time clock is used to set the time and date when the unit is started, but then its
own time and date is maintained, unless a change to the time and date parameters occur,
when it will be updated to the new settings.
The system can set or correct its system clock from information received from an SNTP
Time Server. More specifically it supports SNTP V4 and also Microsoft Windows Time
(W32Time), which means that it supports NTP V3.
The user can enter the IP address of the SNTP server to be used, the default address is
000.000.000.000, which indicates to the system that no SNTP server has been defined,
and therefore SNTP is disabled.
If an SNTP server is defined, and it fails to respond, then an SNTP Server Timeout alarm
will be raised. This alarm will be de-asserted either when an SNTP response is received, or
the SNTP functionality is disabled.