GE864 Hardware User Guide
1vv0300694 Rev.10 - 10/06/08
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 48 of 69
The GPIO4 pin, when configured as RF Transmission Control Input, permits to disable the Transmitter
when the GPIO is set to Low by the application.
In the design is necessary to add a pull up resistor (47K to PWRMON).
The GPIO5 pin, when configured as RFTXMON Output, is controlled by the GE864-QUAD / PY
module and will rise when the transmitter is active and fall after the transmitter activity is completed.
For example, if a call is started, the line will be HIGH during all the conversation and it will be again
LOW after hanged up.
The line rises up 300ms before first TX burst and will became again LOW from 500ms to 1sec after
last TX burst.
10.6 Using the Alarm Output GPIO6 The GPIO6 pad, when configured as Alarm Output, is controlled by the GE864-QUAD / PY module
and will rise when the alarm starts and fall after the issue of a dedicated AT command.
This output can be used to power up the GE864-QUAD / PY controlling micro controller or application
at the alarm time, giving you the possibility to program a timely system wake-up to achieve some
periodic actions and completely turn off either the application and the GE864-QUAD / PY during sleep
periods, dramatically reducing the sleep consumption to few μA.
In battery-powered devices this feature will greatly improve the autonomy of the device.
NOTE: During RESET the line is set to HIGH logic level.