GE9
GE9
GE9
GE910 Hardware User Guide
10 Hardware User Guide
10 Hardware User Guide
10 Hardware User Guide
1vv0300962 Rev.4 2012-06-25
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
page 54 of 73
Mod. 0805 2011-07 Rev.2
11.2.
Using a GPIO Pad 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.
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 GE910 when the module is powered off or during
an ON/OFF transition.
11.3.
Using a GPIO Pad 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.
