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Octolively Kit

htezhtez
in LED Matrix Kits

Hello all,

i recently decided to make up 5 Octolively LED kits.
After soldering 3 together and testing them I was very happy with the soldering and could see that everything was working perfectly.
Then I connected the 3 boards together using the male female connectors and plugged the DC input into the 1st board. I am using a plug with adjustable voltage from Maplins. The plug is set to 1amp and I have adjusted the voltage to 5v (which worked perfectly on each individual board when tested).

I then switched on the power and nothing. Now none of the boards work together or even individually. There is no observable evidence of any fried parts and it doesn't make sense to me that the boards worked fine on their own at the 5v 1 amp setting but then fried when plugged in together to the same power source at the same setting. Perhaps i'm being stupid here?

What are my best solutions?

-Can i simply replace the AT mega chip on each board and put the source code onto each chip manually? (not sure if the source code is available online but I am sure I can pull it off 1 of the other unassembled octolively kits i have and get the code off using an arduino).

What did do wrong and how should I power the units differently to avoid the same mistake again?
-does anyone recommend a plug I can buy that powers 5 of these things together well?

Would really appreciate some help! :(

Thanks,

htez

Comments

  • Windell OskayWindell Oskay

    The first question is whether the power supply is still working. Try measuring it directly, to see what it's actually outputting.

    As to the solution, that depends a great deal on what is wrong. If the power supply is damaged, you'll need to replace it. The microcontrollers are quite tough, and rarely get damaged, even by brief overvoltage or reverse voltage. They can, rarely, get into a situation where they need to be reflashed, and yes, our source code is available online.

    We do sell power supplies that work well to power multiple boards; our 5 V 1 A board powers up to 5 Octolively modules and our 5 V 3 A board powers up to 15 Octolively modules.

  • htezhtez

    HI again,

    Thanks for the comment Windell.

    I've tested my power source and as far as I can tell the power source is fine. I tested it using the guidelines in this YouTube video

    However after doing some testing i noticed when my dc supply was set to 5 volts it was outputting 6.22 volts. I have tested the DC plug also on 3v, 4.5v, 5v 6v, 9v and 12v and each time it is outputting at least 1 volt more than is listed (although i feel like this is standard).

    Could this be the reason the boards fried? Surely not?
    -With this in mind would you consider just 're-flashing the boards'. If so are you able to run me through the process?Alternatively what would you suggest?

    Thank you very much for your help I greatly appreciate it!

    Best,

    Hugh

  • Windell OskayWindell Oskay

    Hi Hugh,
    Yes, that certainly could explain it. As it says on both the product pages and in the documentation, Octolively requires a regulated 5V power supply. A regulated power supply typically keeps the output voltage within about 1% of the nominal value. An unregulated power supply like the one that you have may give 6 V before being plugged in, but may droop as low as 3 V once under power. This is not a safe or reliable way to drive these modules.

    A value greater than 5.5 V can potentially (but does not usually-- these are tough chips) permanently destroy the AVR microcontroller. It is also possible that the program was corrupted due to some unfortunate timing coincidence of the power dropout.

    You could certainly attempt to reflash the chips, or you could send them back to us for reflashing (no cost except postage), or order a set of pre-flashed replacement chips.

    If you'd like to reflash them yourself, you'll need an AVR ISP programmer, or you can substitute (for example) an Arduino, using the ArduinoISP method. The source code is available here: https://github.com/evil-mad/Octolively

  • htezhtez

    Hi Windell,
    Thanks for the response. I think I will simply order some pre-flashed replacement chips, are you able to send a link to where I can buy some?

    In addition to the above I will also buy x2 power sources that you recommended previously, are you able to send a link for this also?

    Kind regards,

    Hugh

  • Windell OskayWindell Oskay

    Here is our 5 V, 3 A power supply: https://emsl.us/487

    Our pre-flashed microcontrollers are here; select your chip and program: https://emsl.us/132

  • htezhtez

    Thanks Windell, youdamman!

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