I am trying to figure out the easiest way to have a bunch of LEDs alternate glowing continuously. I want to open a box and the lights to go on intermittently. Would I use a 555 timer or something else. And if so, how?
thanks, Paul
And the sequencing should seem fairly random.
Hmmm, go to the dollar store and pick up a few 1$ fiber optic trees with RGB LEDs in them. These things cycle across all kinds of colors too. When you get bored of them, lots of parts are already laid out for you to tinker with.
Use a PIC, of course.
-- Many thanks, Don Lancaster voice phone: (928)428-4073
uC preferred but if that scares you then..
MLS (maximum length sequence) generator. This uses a shift register + logic gates. Use RC networks to get the glow effect. D from BC
Make up 3 or 4 strings consisting of LEDs (say 4 leds), a current limiting resistor and a "flashing" LED (the ones with the integrated flashing circuitry) in series. Put the 3 or 4 strings all in parallel. The flashing LEDs flash at a slightly different rate to each other giving a random flashing effect. "Mix" up the locations of the LEDs so they are not all in the same area / line etc. Works well for little christmas trees.
See how this goes:
|---->|---->|---->|---->|------>|----/\/\/\/---------| | | |---->|---->|---->|---->|------>|----/\/\/\/---------| | | |---->|---->|---->|---->|------>|----/\/\/\/---------| | | |---->|---->|---->|---->|------>|----/\/\/\/---------| | | | ^ | pos flasher gnd/neg
It worked for me, ymmv.
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