[TriEmbed] NRF24L01+ Based Large LED Array control - TriEmbed Digest, Vol 24, Issue 2

[Terry King]

Hello Michael,

The nRF24L01 could work for this; there is the ability to talk to multiple units and also "RF24"
has a library for a mesh type network, I think.

See:  http://arduino-info.wikispaces.com/Nrf24L01-2.4GHz-HowTo

and: http://maniacbug.github.io/RF24Network/index.html

Regards, Terry King
...In the Woods in Vermont USA
terry at terryking.us

DISCLAIMER: Mentioned stuff I do sell in my own shop...

-The One who Dies with the most Parts LOSES. What do you need??

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Message: 1
Date: Fri, 01 May 2015 21:15:48 -0400
From: Michael Fulbright <mike.fulbright at pobox.com>
To: triembed at triembed.org
Subject: [TriEmbed] NRF24L01+ Based Large LED Array control
Message-ID: <55442544.4060202 at pobox.com>
Content-Type: text/plain; charset=utf-8; format=flowed

I've been following the large scale building lighting project and it
sounds cool.  I was thinking about it some driving home today and
wondered if the simple NRF24L01+ modules wouldn't work.  These are $1
each and have the typical 30m indoor range (depending on walls, etc) and
can be run between 200 Kbit/sec to 1.5 Mbit/sec as I recall.  I use them
for remote sensors I built and put all over the house.   They work at
2.4GHZ as I recall.

I would think you could have a master at the base level of the building
and each "refresh cycle" for the display you would have the master send
a message which encoded the display contents (which building levels are
on/off).  If all of the lighting nodes would just be listening nodes so
this is easy.  The first floor light will receive the message from the
master, put its light in the correct state, then temporarily go into
xmit mode and repeat the message, then return to listening mode.  The
second floor would either have already received the masters message or
more likely the repeated message from the 1st floor.  Then goes on until
the final floor receives a message.  It would take a little
experimenting but I think you could easily support a refresh rate of
several HZ using this.  The nice thing is you can add as many nodes as
you want and as long as the message encodes each nodes state then you
really have no configuration except teaching each node what its address
is (so it can pick out its state from the message).

The message could be a simple bit-encoded state array so it would be
quick to xmit.

Just an idea based on some things I've played with.  The NRF20L01+
modules have fairly robust support for Arduinos so you could get the
cost for a single node down to almost single digits if you use really
cheap Arduinos (not including the cost of the LED strip controller, but
that is a fixed cost we can't control).

Michael Fulbright

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