Real Time Clock - Motorola G24 Developer's Manual

Real Time Clock

G24 incorporates a Real Time Clock (RTC) mechanism that performs many internal functions,
one of which is keeping time. The RTC subsystem is embedded in the PMIC and operates in all
of the G24 operating modes (Off, Idle, Sleep), as long as power is supplied above the minimum
operating level.
The G24 time and date can be set using the following methods:
•
Automatically retrieved from the GSM network.
In case G24 is operated in a GSM network that supports automatic time zone updating, it will
update the RTC with the local time and date upon connection to the network. The RTC will
continue to keep the time from that point.
•
Using the AT+CCLK command.
Setting the time and date manually by this AT commands overrides the automatic network
update.
Once the time and date are manually updated, the RTC timer will keep the time and date
synchronized regardless of the G24 operating state.
When the power supply is disconnected from G24, the RTC timer will reset and the current time
and date will be lost. On the next G24 power-up the time and date will need to be set again
automatically or manually.
January 1, 2006 Module Hardware Description
Chapter 2: Hardware Interface Description
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