User's Manual

LE910 V2 HARDWARE USER GUIDE 1VV0301200 Rev.2 Preliminary • 2015-08-04 47 of 81

5.6.1 Using a GPIO as INPUT

The GPIO pads, when used as inputs, can be connected to a digital output of another device and report its status,

provided this device has interface levels compatible with the 1.8V CMOS levels of the GPIO.

If the digital output of the device to be connected with the GPIO input pad has interface levels different from the

1.8V CMOS, then it can be buffered with an open collector transistor with a 47K pull up to 1.8V supplied by

VAUX/POWERMON R11 pad.

NOTE:

In order to avoid a back powering effect it is recommended to avoid having any HIGH

logic level signal applied to the digital pins of the LE910 V2 when the module is powered

off or during an ON/OFF transition.

5.6.2 Using a GPIO as OUTPUT

The GPIO pads, when used as outputs, can drive 1.8V CMOS digital devices or compatible hardware. When set

as outputs, the pads have a push-pull output and therefore the pull-up resistor may be omitted.

5.6.3 Indication of network service availability

The STAT_LED pin status shows information on the network service availability and Call status.

The function is available as alternate function of GPIO_01 (to be enabled using the AT#GPIO=1,0,2 command).

In the LE910 V2 modules, the STAT_LED needs an external transistor to drive an external LED and its voltage level

is defined accordingly to the table below:.

Device Status

Led Status

Device off

Permanently off

Not Registered

Permanently on

Registered in idle

Blinking 1sec on + 2 sec off

Registered in idle + power saving

It depends on the event that

triggers the wakeup (In sync with

network paging)

Voice Call Active

Permanently on

Dial-Up

Blinking 1 sec on + 2 sec off