8. OPERATION
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LZ T 123 7 605 P1C
8.5 Power Save
The Control Terminal can power down the main RS232 IC when not
needed in order to minimise power consumption. The IC is powered up
automatically at start-up but can be powered down by setting the output
of IO2 on the embedded Radio Device (pin22) to low via AT command or
embedded application. Once powered down, the IC can be woken up by
setting the output of IO2 high on the Radio Device via AT Command.
Even when powered down the IC is able to pass a DTR signal received on
the serial interface. Therefore an embedded application that monitors
DTR, while the IC is powered down, can be made to wake up the IC, if a
signal is received, by setting IO2 on the Radio Device high.
8.6 Controller Mode
The Control Terminal, when powered up, will normally start up its GSM
signalling software and look to register on the GSM network. Any
embedded application script runs as a background process as and when the
GSM software is idle. A feature available via embedded applications allows
the Control Terminal to be placed in ‘controller mode’ whereby the Control
Terminal powers up with a minimal subset of radio functionality. The
GSM signalling software is halted and the embedded applications script
has full control of the processor.
Controller mode allows an application to run with more predictable
response times.
Operating state
LED
After switching on the Control Terminal
On after 4s
Control Terminal switched off or power removed from the
module
Off
Standby or talk
Flashing
No network, network search, no SIM card, no PIN entered
On