Newbie with Big Project Goal - 25 LED Candles wireless control

Discussion in 'Embedded Systems and Microcontrollers' started by dreamwrx, Oct 3, 2014.

  1. dreamwrx

    Thread Starter New Member

    Oct 3, 2014
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    Hi I am interested in controlling 25 LED modules (each module with RGB LED) wirelessly (433mhz which is cheaper than wifi).

    My ultimate goal is to build a program that will let me run these modules synchronously with a song. I don't know if it would be better that these modules store specific programs they execute or if there is master controller that tell them simple commands via radio/wifi.

    Basically I want to do this:

    I am not an electrical engineer so treat me like an fool please. Any help is appreciated. I just have no idea where to start.

    In all honestly I would like to do this for my wedding reception and cost is a major factor so I would like to do this as cost efficient as possible.
     
  2. R!f@@

    AAC Fanatic!

    Apr 2, 2009
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    The lighting could be pre programmed to the source by the way I see the lights are working.
    Or it could be tht the light controller is frequency depended or may be loudness depended.

    I can not say for sure how the LED controller switching is done.
    Lets see any one else has any idea.
     
  3. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    My guess is that there is a master controller. Synchronization would be nigh impossible otherwise. The master controller would address each "candle" and color. For 25 candles, this can be done with a byte (5 bits for the candle and three bits for the color). A second byte would defne the brightness. You might need a third or fourth bytes to frame each command.

    The lighting sequence would be preprogrammed in the master controller. The master controller could start the music to synchronize it. The sequence of lighting commands would be broadcast from the master controller and each candle would only respond to the command addressed to it. (Those first 5 bits, remember?)

    Each candle would need a microcontroller ($2-3) and a 433MHz receiver ($3), plus miscellaneous components.

    Programming the custom protocol would be a challenge, but do-able.

    Just blue-skying.
     
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  4. dreamwrx

    Thread Starter New Member

    Oct 3, 2014
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    Awesome!!! those are some great Ideas... now if you guys would kindly point me in the right direction to start this epic project i would greatly appreciate it.

    What master controller should I be looking at?
    Ideas for the transmitter/receivers?
    Which microcontroller would be enough to control 3 LEDs maybe even add in PWMs (for Candle lighting effect)?

    Thank you very much for your inputs!!
     
  5. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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  6. dreamwrx

    Thread Starter New Member

    Oct 3, 2014
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    I noticed those transmitters & receivers too. But I'm stuck on how to choose the right MASTER controller and if its possible to even transmit to that many devices?
     
  7. sirch2

    Well-Known Member

    Jan 21, 2013
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    there are lots of cheap ISM band (433Mhz, etc) transmitter and receivers available. I would avoid the really cheap ones as they can be hard to work with. http://www.rfsolutions.co.uk/ is one company that I have used in the past and their modules seem ok.

    With these low cost modules you will need your own protocol for sending data. If I understand your requirement correctly you only need one transmitter and then a number of receivers. One system I have used in the past is to send out a pulse train starting wit say 5 long (around 5kHz pulses) as a handshake and then send a number of quicker (around 10kHz) pulses that contain the data. So your receiver listens for the long pulses, it may miss the first one or two but once it gets a number of 5kHz pulses it then checks for half-width (10kHz) pulses, if it gets a 10k pulse it starts counting. In your application you could send an number of pulses as an identifier to identify which "candle" should light and then send another set of pulses (at a different frequency or with some kind of separator) to identify the colour.

    There are more sophisticated encoding schemes for sending serial data but keeping it simple is often good.
     
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  8. dreamwrx

    Thread Starter New Member

    Oct 3, 2014
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    I guess I gotta get something to build and try first before attempting to go all 25. I don't know what master to handle communications though.

    So I am understanding that what I would need to do is:

    PC -> Master Controller/Transmitter -> Receiver/microcontroller -> LEDs

    As such I guess I would like to run a preset program from the PC that the master controller would run (like a certain song or sequence.)
     
    Last edited: Oct 6, 2014
  9. dreamwrx

    Thread Starter New Member

    Oct 3, 2014
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    I got some Arduino clones for pretty low cost I will try them out with the RF transmitters. I just have to start somewhere.

    Thank you for pointing me in the right direction. I will post if I have other questions.
     
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