Technical information

Chapter 2: Hardware Interface Description
December 15, 2009 G30 - Module Hardware Description 19
The G30 wakes up periodically from low power mode to page the GSM network for any
incoming calls or data. After this short paging is completed, G30 returns to low power mode.
During this short awake period, the serial interfaces are enabled and communications with the
module is possible.
The CTS signal is alternately enabled and disabled synchronously with the network paging cycle.
CTS is enabled whenever G30 awakes to page the network. This indicates the G30 serial
interfaces are active (see Figure 2-7).
Figure 2-7: CTS Signal During Sleep Mode
The periodical enabling and disabling of the CTS signal during low power mode can be
controlled by the AT+MSCTS command.
Setting AT+MSCTS=1 permanently disables the serial interface during low power mode, even
during a network page by G30. The CTS signal is disabled, and therefore the serial interfaces are
blocked.
Terminating Low Power Mode
Terminating the low power mode, or wake-up, is defined as the transition of the G30 operating
state from Sleep mode to Idle mode. There are several ways to wake-up G30 from low power
mode as described below.
Important: During power saving mode the G30 internal clocks and circuits are disabled, in
order to minimize power consumption. When terminating the power saving mode,
and switching to Idle mode, G30 requires a minimal delay time to reactivate and
stabilize its internal circuits before it can respond to application data.
This delay is typically of 15 milliseconds, and is also indicated by the CTS signal
inactive (high) state. The delay guarantees that data on the serial interface is not lost
or misinterpreted.