DMD Duplicate Panels

The Dot Matrix Display (DMD) is a 32x16 array of high-brightness LEDs for visually striking effects. [Product Page]
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Wayne2Sanders
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Joined: Sun Mar 16, 2014 7:57 pm

DMD Duplicate Panels

Post by Wayne2Sanders » Tue Mar 25, 2014 1:00 am

Can one duplicate 2 DMD panels , or is it easier to buy another Eleven?
:D

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stryker
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Re: DMD Duplicate Panels

Post by stryker » Tue Mar 25, 2014 9:52 am

Hi,

I'd be tempted to parallel the data lines and split them out to two DMDs which will need an independent power supply as that's too much to power using the data line alone. At first blush I can't see a reason why that shouldn't work, but won't get a chance to try it for you for the next couple of nights so hopefully someone else can confirm if you're in a hurry.
Wayne2Sanders wrote:or is it easier to buy another Eleven? :D
In my experience it's easier or cheaper, but rarely both.

Cheers ! Geoff

Wayne2Sanders
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Re: DMD Duplicate Panels

Post by Wayne2Sanders » Tue Mar 25, 2014 3:39 pm

Thanks for the thoughts , no hurry.

Brissieboy
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Re: DMD Duplicate Panels

Post by Brissieboy » Wed Mar 26, 2014 10:35 am

Wayne2Sanders,

I agree with stryker - All the connections between the DMD and the Arduino are one-way. There is no handshaking or anything similar going on. And there should be plenty of drive from the Arduino data lines to handle the load of 2 DMDs in parallel.

But definitely use a good solid 5V supply for the DMDs - don't attempt to run them via the Arduino/USB power. Despite being fairly common, it is definitely not good practice.

Let us all know how you go please.

Wayne2Sanders
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Joined: Sun Mar 16, 2014 7:57 pm

Re: DMD Duplicate Panels

Post by Wayne2Sanders » Tue Apr 01, 2014 1:28 am

I chickened out and used 2 boards....
Going to have a play when things quiten down - work is mucking up my week !!

Aussie_Wombat
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Location: Adelaide, South Australia

Re: DMD Duplicate Panels

Post by Aussie_Wombat » Sun Apr 06, 2014 12:43 am

Because the DMD's use spi, can't you just connect the two dmd's in series, and set the arduino to only one panel, the data will flow through the first panel into the next panel, but I think the data will be one line lower on the second panel..

AussieWombat

Brissieboy
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Re: DMD Duplicate Panels

Post by Brissieboy » Sun Apr 06, 2014 9:59 pm

Aussie_Wombat,

I don't think so. The first DMD will not output anything to the second until it has received the full set of data. That is the way shift registers work.

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