User's Manual

DE910 Series Hardware User Guide
1vv0301183 Rev.1 – 2015-2-13
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Reserved. Page 22 of 70
4.2. Turning off the DE921 module
Turning off the device can be done in two ways:
 By software command (see DE921 Software User Guide)
 By hardware shutdown
When the device is shut down by software command or by hardware shutdown, it issues a
detach request to the network that informs the network that the device will no longer be
reachable.
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 DE921 when the module is powered OFF or
during an ON/OFF transition.
The following flow chart shows the proper turnoff procedure: