User Manual

852 Hz

941 Hz

The GSM/WCDMA system architecture defines that the audio signal of the DTMF tones is

inserted by the network switches on commands sent by the Mobile Station (MS). Thus, the

default duration parameters may vary from network to network. In case that the devices are

controlled by DTMF, they become sensitive related to the duration of the tones and timing of

the sequences. Dedicated investigations on the parameter settings must be made.

The Telit HE910V2 family has a special function that reduces power consumption during idle

time, thus allowing a longer standby time with a given battery capacity.

This function monitors the DTR line and USB VBUS line indicating that the OEM

application is ready to send commands when DTR goes high (3V on UART) and USB VBUS

goes low (0V on USB). If so, the OEM application is not going to send any commands and

the HE910V2 family module can save energy by shutting down its internal serial port or USB

port.

When the OEM application becomes ready again, the line DTR is tied low (0V on UART) or

VBUS is tied high (5V on UART); the HE910V2 family detect this condition and powers up

the serial port or USB port.

If the power saving function is activated, then the serial port must support the DTR line since

when this line is high (Data Terminal is NOT ready) and the USB port must support the

VBUS line since when this line is Low the device goes into a sleep condition and will not

respond to commands until the DTR is tied low (Data Terminal is ready) or the VBUS is tied

high.

 send command AT+CFUN=<fun><cr>

where:

<fun> is the power saving function mode, the supported values are:

0 - minimum functionality, NON-CYCLIC SLEEP mode: in this mode, the AT interface is

not accessible.

1 - mobile full functionality with power saving disabled (factory default)

2 - disable TX

4 - disable both TX and RX

5 - mobile full functionality with power saving enabled

 wait for response: