Telegesis HA 101
Even though the Telegesis HA
solution is designed to be friendly to
the nontechnical user, we will
approach it from a technical point of
view. This HA package consists of
standard 802.15.4-based ZigBee
radios that are loaded with a ZigBee
PRO stack and custom firmware. The
custom firmware is written to follow
the ZigBee Home Automation Public
Access to the Telegesis ZigBee
HA profile is provided by Hayes-like
AT commands. The AT command set
shields the user from the
complexities of the ZigBee stack and
exposes an easy to understand HA
The Telegesis solution is
implemented using their ETRX357
ZigBee radio module. The custom
ZigBee HA firmware comes in two
flavors. The Combined Interface
firmware runs on an ETRX357
module that is under the control of a
mains powered device such as a PC.
Five-In-One firmware resides on
ETRX357-hosted endpoints which can
be battery powered.
The endpoint firmware has the
ability to service multiple monitor
and control functions using a single
ETRX357 radio. Since there are five
logical endpoints encapsulated in a
single hardware endpoint, the
firmware name Five-In-One is a
In the lighting area, two of the
five endpoints perform light on/off
and light dimmer functions.
Temperature and illuminance sensing
in addition to an on/off switch
function round out the five endpoints
targeted by the Telegesis HA
development kit. The five endpoints
are accessed with commands that
are transmitted by the Combined
Nuts and Volts
The Five-In-One device is
These days, one would be
hard pressed to find a
household gadget that isn't
in some way automated.
Take a trip to your local
home improvement store.
You'll find that you can
purchase a thermostat that
plays on your household
LAN and can be controlled
from anywhere by way of
your Android cell phone.
Your garage door can be
put under the control of
another app residing in that
same phone. If today's
technology is applied
accordingly, every appliance
in your home down to the
coffee maker has the
opportunity to be remotely
controlled and monitored.
For those with deep
pockets, home automation
is just another purchase.
For those with little to no
technical savvy, home
automation is out of reach.
Well, at least it used to be.
This month's discussion
will revolve around a
automation (HA) package
offered by Telegesis.
Absolutely zero ZigBee
technical knowledge or a
third mortgage is required
to put the Telegesis home
automation radios to work.
THE DESIGN CYCLE
Go to www.nutsvolts.com/index.php?/magazine/article/
september2013_DesignCycle for any additional files and/or
downloads associated with this article. You can also discuss
this topic at http://forum.nutsvolts.com.
■ Photo 1. This
is an aerial view
of the Five-In-One device that
is part of the
and LEDs can be
accessed via the
ADVANCED TECHNIQUES FOR DESIGN ENGINEERS ■ BY FRED EADY
September 2013 57