police siren

Using Arduino LEDs and Multiplexing
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Hi everyone
I would want to do something like a police siren with 12 RGB leds. As I want to control them individually I need 36 pins and I think that there´s a lot (i would need arduino mega and it consumes a lot of battery)
could you recommend me something???? And... I have seen that using random pins for my RGB led it does not work equally; could you tell me why????
I´m noob

Thanks

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Please read the forum guide in the sticky post, then modify your post above so that we have some chance of helping you.

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You can consider an addressable LED strip. That will only cost you one pin.

You can also consider multiplexing (there is a section on the forum for that).

Regarding power consumption, the two determining factors are how many leds are ON at a time and how bright you want them to be.

Telmooo:
And... I have seen that using random pins for my RGB led it does not work equally; could you tell me why????

Please explain in detail.

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