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Putting 3 MiniPovs together
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Putting 3 MiniPovs together

by Greasetattoo on Tue Oct 17, 2017 8:39 am

Hey all,

I have a simple question.

If I were to put 3 of the MiniPovs together, would it work?
Like instead of 8 pixels, I would have 24 pixels.

I would just tape them together and when I made my design, just split it up in 3's.
Put 1/3 of the design on each POV.
All the POVs would be separate, though...


Would it work?

Greasetattoo
 
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Re: Putting 3 MiniPovs together

by adafruit_support_rick on Tue Oct 17, 2017 10:06 am

Wellll ... maybe. The problem will be synchronizing the three displays. You'll have to get them all to start the pattern at the same time, and you'll have to get them all to run it at the same speed.

I imagine you would have to modify the hardware and firmware to create some sort of synchronization - Maybe have a single button someplace that causes them all to start at the same time. Getting the speed right is a little more difficult.
The firmware does an analog read of the pot to set the speed. You should be able to use a single pot and have all three processors read the same pot. But there will be slight differences in the reading between the three processors, since there will be voltage variations between the battery packs. You can get rid of a lot of that by setting the analog input to use an external analog reference. Tie the AREF pin on each processor to the same battery. Or just use one battery pack for all three (an external reference might still work better, though).

Actually, a better approach would be to control all the timing from a single processor. What you would do is modify the timer-based interrupt service routine on the first POV to toggle a digital write on an output pin. Wire the pin to an external interrupt pin on each of the other two POVs. Modify the ISR on the other two POVs to respond to the external interrupt instead of to the timer interrupt.

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