I need some peggy advice please.

jimcanswim

Hi, I am new to all this so please bear with me.

I want to make a few marine charts with bouys which flash in a certain sequence. What would be the most suitable thing? Peggy 2? Peggy seems a bit overkill though.

I want to have about 60 Leds that flash in different sequences, I will have to wire each led to a flying lead and connect this to peggy, which seems quite difficult.

Also what are they physical dimensions of peggy and what duration does the batteries have?

Thanks for any advice.

Windell Oskay

The Peggy 2 (or 2LE) can do it, but it is indeed overkill. Probably the most straightforward way to use it would be to wire up 6 rows rows of 10 LEDs each, meaning that you'd need to run a total of 16 wires to the Peggy.

The Peggy 2 is 11.320x14.875" in overall size:

 http://shop.evilmadscientist.com/productsmenu/tinykitlist/75-peggy2

You might prefer to use the Peggy 2LE instead, as it is smaller (9.625x5.9") and lower in cost:
http://shop.evilmadscientist.com/productsmenu/tinykitlist/157

The Peggy 2 comes with a 3xD battery holder. One can be added separately to the Peggy 2LE as well: http://shop.evilmadscientist.com/productsmenu/partsmenu/552

I'd estimate battery lifetime under this set of circumstances as about 150-250 hours if the LEDs are on all of the time, and 2-5 times that if the LEDs are flashing intermittently.  I'd certainly recommend turning it off when not needed or (much better) using a plug-in power supply.

Since you don't need all that many LEDs, and they don't need to be on all the time, you might consider using Charlieplexing, directly from a microcontroller, to drive the LEDs instead.   For 60 LEDs, you could do this with a microcontroller board like our Diavolino, using 9 digital output lines to drive a hand-wired matrix.  For a bit more about Charlieplexing, see our article about how the Bulbdial Clock works:

 http://www.evilmadscientist.com/2010/on-the-design-of-the-bulbdial-clock/