GE/GC864-QUAD V2 and GE864-GPS Hardware User Guide
1vv0300915 Rev.5 – 2011-10-03
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved.
Page 67 of 94
GPIO6 supports all three modes and can be input, output, alarm output (Alternate
function)
GPIO7 supports all three modes and can be input, output, buzzer output
(Alternate function)
11.1.
GPIO Logic Levels
Where not specifically stated, all the interface circuits work at 2.8V CMOS logic levels.
The following tables show the logic level specifications used in the GE/GC864-QUAD V2
and GE864-GPSinterface circuits:
Absolute Maximum Ratings
–
Not Functional
Parameter
Min
Max
Input level on any
digital pin when on
-0.3V
+3.1V
Input voltage on analog
pins when on
-0.3V
+3.0 V
Operating Range
–
Interface Levels (2.8V CMOS)
Level
Min
Max
Input high level
2.1V
3.1V
Input low level
0V
0.5V
Output high level
2.2V
3.0V
Output low level
0V
0.35V
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 2.8V
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 2.8V CMOS, then it can be buffered with an open collector transistor with a
47K pull up to 2.8V, this pull up must be switched off when the module is in off condition.
