User guide

UC864-E/G/WD/WDU Hardware User Guide

1vv0300766a Rev.4

- 03/02/09

11.4. Using the RF Transmission Control GPIO4

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

it is necessary to add a pull up resistor (47K to PWRMON).

11.5. Using the RFTXMON Output GPIO5

The GPIO5 pin, when configured as RFTXMON Output, is controlled by the UC864-

E/G/WD/WDU 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 conversations and it

will be again LOW after hanged up.

The line rises up 300ms before first TX burst and will become again LOW from

500ms to 1sec after last TX burst.

11.6. Using the Alarm Output GPIO6

The GPIO6 pad, when configured as Alarm Output, is controlled by the UC864-E/G

/WD/WDU 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 UC864-E/G/WD/WDU controlling

microcontroller 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 or the UC864-E/G/WD/WDU during sleep periods. This will

dramatically reduce the sleep consumption to few μA.

In battery-powered devices this feature will greatly improve the autonomy of the

device.

11.7. Using the Buzzer Output GPIO7

As Alternate Function, the GPIO7 is controlled by the firmware that depends on the

function implemented internally.

This setup places always the GPIO7 pin in OUTPUT direction and the corresponding

function must be activated properly by AT#SRP command (refer to AT commands

specification).

NOTE:

During RESET the line is set to HIGH logic level.