User's Manual

CE910-DUAL Hardware User Guide

1vv0301010 Rev .0 – 2012-07-10

During the Initialization state, any kind of AT-command is not available. DTE must wait for

the Activation state to communicate with CE910-DUAL.

To check if the CE910-DUAL has powered on, the hardware line VAUX/PWRMON must be

monitored. When VAUX/PWRMON goes high, the module has powered on.

NOTE:

Do not use any pull up resistor on the ON_OFF* line. It is pulled up internally. Using a pull

up resistor may bring latch up problems on the CE910-DUAL power regulator and improper

power on/off of the module. The line ON_OFF* must be connected only in open collector

configuration.

NOTE:

In this document all the lines are inverted. Active low signals are labeled with a name that

ends with "*" or with a bar over the name.

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 CE910-DUAL module when the module is

powered OFF or during an ON/OFF transition.

For example:

1. To drive the ON_OFF* pad with a totem pole output of a +3/5 V microcontroller

(uP_OUT1):