Technical information

Chapter 5: JAVA API
July 15, 2008 G24 KJAVA User’s Guide 5-5
Note:
• USB device connected to G24 will prevent unit from entering sleep mode.
• If data (Serial Logs or Comm Connection) is not being read by external device
(remains in UART1 or UART2 buffers) G24 will not enter Sleep Mode.
• To reduce power consumption to minimum, Kmgr pin time sample (polling) should be
reduced respectively. Use setProperty("oem.kmgrpin.timesample",XXX).
Airplane Mode
When "Airplane" mode is turned on, all transmit and receive RF circuits are disabled and
Network related classes will throw an exception, if accessed:
• SocketConnection
• UDPDatagramConnection
• SocketServerConnection
• HTTPConnection
After power cycle, G24 restarts in normal mode, i.e. RF operations are enabled, even if in the
previous session they were closed.
Real Time Clock (RTC) Mechanism
The RTC mechanism consists of two parts:
1. "Time and Date" - contains current date and time synchronized with Network time.
2. "Alarm" - contains some pre-installed date and time.
The RTC mechanism operates in all of the G24 KJAVA operating modes (Off, Idle, Sleep) as long
as the power supplied is above the minimum operating level, see reference [1]. If the power
supply is physically disconnected from the G24, the RTC timer resets and all the time, date and
alarm settings are lost. On the next G24 power-up the time and date will revert to a default value.
The currently default is "00:00:00 01-Feb-07" (This value may be changed in further versions).
Time and Date
The OSC class provides the ability for the UM to accept or to decline Network NITZ update.
There are two ways to set "Time and Date" to be available:
• By auto update - if network supports NITZ and UM enables this feature.
• Direct set - if UM disables auto update and manually set Time and Date.
After power cut "time and date" will be reset and not be available until next set.
If network does not support Network NITZ update it is recommended not to enable auto update.
Alarm
Enable the user to set a time for an Alarm event to occur. This event will take place when "Time
and Date" becomes equal to Alarm's setting time.
This feature can be used to automatically switch the module ON at a pre-defined time (can be
used to save battery power).