Ultra basic LED flasher

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi all.

I need to find a way to make a number (say 16) of LEDs flash concurrently at a set rate, with the option of flash, constant on, or off.

I know this should be easy, but I need to check a few things before I start playing.

I need to embed the whole circuit in a small item of clothing so am planning to use the arduino nano. Could someone tell me how the LEDs will need to be wired to this? Do they need to be in series or parallel? Will each LED need an accompanying resistor? And what kind of battery life couuld I expect from for example, 2x 3v 260mAh button cells?

Thanks in advance for any answers/ideas!

Will

2

For the simple flashing you're talking about doing, I wouldn't bother with an Arduino: I'd use a CMOS 555.

You need to pick your LEDs carefully, and immediately: voltage requirements for common LEDs can range from about 1.7 to 3.5V. So it's impossible to tell you how to wire them up, or what battery life to expect, until you've spec'ed the LEDs.

Ran