Owner manual
 GM862-QUAD / PY Software User Guide 
 1vv0300747 Rev. 3 - 10/07/07  
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved    page 76 of 96 
3.6  Using General Purpose Input/Output pins 
The Telit GM862-QUAD / PY provides various General Purpose Input/Output pins, these pins can be 
configured via AT commands as Inputs, Outputs and two of them as "alternate function". 
The  "alternate  function"  are  supported  by  pins  pins  GPIO4  which  can  be  configured  as  RF 
Transmission  Control input pin,  GPIO5, which can be  configured to become  a  RF Transmission 
monitor output  pin that reflects the RF transmission activation,  GPIO6, which can be configured to 
become an alarm output pin that reflects the alarm status, and GPIO7 which can be configured to 
become a buzzer output pin. 
With these pins your application can control external hardware directly using the Telit GM862-QUAD / 
PY pins, with little or even no hardware added. 
3.6.1  GPIO pin setup 
Before using the GPIO pin, you must configure them to select their direction or alternate function 
3.6.1.1 Setting GPIO pin as OUTPUT 
When you set a GPIO as output, you must specify also the value that the pin output must take: 
•  Send command 
AT#GPIO=<pin>,<value>,1<cr>
where: 
<pin> is the GPIO pin number at which the command applies: 
        7 – GPIO7 
2 – GPIO2        8 –  GPIO8 
3 – GPIO3        9 –  GPIO9 
4 – GPIO4        10 –  GPIO10 
5 – GPIO5        11 –  GPIO11 
6 – GPIO6        12 –  GPIO12 
          13 – GPIO13 
<value> is the GPIO pin value that the pin will assume: 
0 – LOW   
1 – HIGH 
•  wait for response 
OK
NOTE: The #GPIO setting is not saved and will be lost on power off, so at start-up repeat pin 
initialization commands. At start-up the setting for GPIO4, GPIO5, GPIO6 and GPIO7 instead is 
maintained even after a shutdown to permit the Alternate feature to work always. 










