More LEDs and Different colours ???

MiniPOV4 and previous versions

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ali89ma
 
Posts: 3
Joined: Thu Jul 16, 2009 1:04 am

More LEDs and Different colours ???

Post by ali89ma »

Hi,
What do i need to do if i want to add more LEDs? Do i need a better microcontroller?
And how about using RGB LEDs, so we can get a picture or something colourful ?

Thanks a lot...

adafruit
 
Posts: 12151
Joined: Thu Apr 06, 2006 4:21 pm

Re: More LEDs and Different colours ???

Post by adafruit »

yes you'd need a bigger microcontroller like the one in an arduino. the minipov3 doesnt have that many pins!

s133p
 
Posts: 9
Joined: Wed Jul 15, 2009 1:37 am

Re: More LEDs and Different colours ???

Post by s133p »

Alternatively you can run quite a few LED's with the attiny2313 (the micro-controller used in the kit), the two possible methods are multiplexing and charlieplexing.

With multiplexing you can run up to N*M led's off of N+M pins. (that makes 72 leds, the limit on the attiny2313 if you dont use the reset pin)

With charliplexing you can run n*(n-1) led's off n pins. (that makes 272 led's, also limited by not using the reset pin)

One thing to take into account is that with either of these methods, the code to light individual leds is more complex and you have to alternate led's on and off very quickly to be able to animate or anything of that sort. There are some good instructables on the topic if you want to learn more.

Hope that helps.

sparr
 
Posts: 196
Joined: Tue Nov 04, 2008 5:21 pm

Re: More LEDs and Different colours ???

Post by sparr »

A third option is to use a shift register, so that you send the data out one byte at a time. This allows you to run infinitely many LEDs from 3-4 pins, at the cost of slower refresh (you have to send out the entire 'list' of LEDs to change one of them).

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