URGENT: Random light circuit

[cimo]

Hi

I am looking for more advice for a simple project: the circuit should light up 4 ultra-bright LEDs randomly, that s it, maybe being able to change the way it behaves would be nice as well..

tx

[TK.]

http://www.free-electronic-circuits.com/circuits/8-random-flashing-leds.html

[cimo]

http://www.free-electronic-circuits.com/circuits/8-random-flashing-leds.html

Hi

I know that circuit, I ve actually won 2 years ago' pumpkin contest in Sahira school with a flashing blue and red pumpkin... scaaaryy

The point is that now I need to flash a single light (4 leds in parallel) at random intervals ..

tx

[TK.]

Ah alright, so you need more randomness for a single light.

I would take a microcontroller (can be a real small one) that outputs a pseudo random pulse train, e.g. with a linear feedback shift register algorithm (LFSR)

Building a LFSR with discrete logic is too complex/expensive.

Using a discrete true random generator (example) is a bit easier to build, but it wouldn't give you enough control about the effect (and this was your request)

Best Regards, Thorsten.

[SLP]

two NE555 (556) and a "AND" gate or something?

[clem!]

Hi,

perhaps this can help to do it software based:

http://courses.missouristate.edu/KenVollmar/MARS/CCSC-CP%20material/Fibonacci.asm

Best regards,

clem!

Randomness is an Illusion