Maintenance; Power Saving; Charging - Siemens TC45 User Manual

TC45 TC45 JAVA User's Guide
Confidential / Released

3 Maintenance

Basic maintenance features of the TC45 are described below. Explicit details of these
functions and modes can be found in the AT Command Set [4] and the Hardware Interface
Description [5].

3.1 Power Saving

The module supports several power saving modes which can be configured by the at
command at+cfun [4]. Power saving affects the Java application in two ways. On the one
hand it limits the access to the serial interface (RS-232-API) and the GPIO pins and on the
other hand 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=5, 6, 7 or 8) 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 it should
be mentioned that the signal must be constant for at least 2.12s to detect changes.
For further details refer to [5].
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. So a Java
application that wants to be power efficient should not have any unnecessarily active
threads (e.g. no busy loops).

3.2 Charging

Please refer to [4] and [5] for general information about charging. Charging can be
monitored by the running Java application. The JVM is active in Charge mode and when
autostart is activated also in Charge-Only mode. 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 [5]
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 API's
without CSD are available. The 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 [6]) on this AT command API instance before passing the first AT command.
TC45_JAVA User's Guide_V02 Page 17 of 72 30.06.2003