Siemens TC65 manual Power Saving, Charging

TC65 JAVA User's Guide	s
Strictly confidential / Released

5.2Power Saving

The module supports several power saving modes which can be configured by the AT command at+cfun [3]. Power saving affects the Java application in two ways. First, it limits access to the serial interface (RS-232-API) and the GPIO pins. Second, power saving efficiency is directly influenced by the way a Java application is programmed.

Java hardware access limitations:

•In NON-CYCLIC SLEEP mode (cfun=0) the serial interface cannot be accessed while in CYCLIC SLEEP mode (CFUN=7 or 9) the serial interface can be used with hardware flow control (CTS/RTS).

•In all SLEEP modes the GPIO polling frequency is reduced so that only signal changes which are less than 0.2Hz can be detected properly. Furthermore, the signal must be constant for at least 2.12s to detect any changes. For further details refer to [4].

Java power saving efficiency:

•As long as any Java thread is active, power consumption cannot be reduced, regardless whether any SLEEP mode has been activated or not. A Java application designed to be power efficient should not have any unnecessarily active threads (e.g. no busy loops).

5.3Charging

Please refer to [3] and [4] for general information about charging. Charging can be monitored by the running Java application. The JVM is active in Charge mode and in Charge-Only mode if autostart is activated. Only a limited number of AT commands are available when the module is in Charge-Only mode. A Java application must be able to handle the Charge-Only mode and reset the module to reinstate the normal mode. See [4] for information about the Charge-Only mode.

The Charge-Only mode is indicated by URC “^SYSSTART CHARGE-ONLY MODE”.

Note: When a Java application is started in Charge-Only mode only AT Command APIs without CSD are available. The mode-indicating URC is created after issuing the very first AT command on any opened channel. To read the URC it is necessary to register a listener (see [5]) on this AT command API instance before passing the first AT command.

TC65 JAVA User's Guide_V05 Page 25 of 90 26.09.2005