i nead a random led driver for 4 leds. im hoping there is one out there that requiers little to no ic's, and that none of the leds blink at the same time. thanks
Little or no ICs. ICs are often easyer to solder, and greatly simpify a design. If you needed more than 4 LEDs i would recomend using a line decoder IC, and some astables (explained a bit below). This wouldn't be that random, but it would look rather random. A line decoder converts a 4bit binary signal, into its value, say you have 010 (2 in binary) then the LED on output2 of the line decoder would light up, all the others would be dim. Say you had 7 LEDs hooked up, then 3 bits would control it. If on each binary input line you had an astable, this is something that produces a square wave. _|`|_ by having 3 of these producing differn't intervals, (length of the rectangle) then you get a rather nice random ish effect, thats nicely repetative. It might not be what your looking for but its very simple, and pleasing to the eye.
I guess you could build the IC with transistors and passive components if you don't want to order anything and that is all you have. You can construct an astable timer, like the 555 IC timer, and use logic gates and makeshift memory transistors to make sure that only one LED stays on at a time. Though like all things, the sequence would not really be random since it has a finite amount of possible sequences that it could carry out.
thanks that helps alot but i have never used estables, or logic gates or the 555 timer, and ic's at all thanks again. if it at all were possible to give me a circuit diagram or explain it a little better that would be great .( mabye i should just read up on ic's or somthing)thanks again.
Parallel port + Windows 2000/XP = a really hard time Windows 2000/XP doesn't allow direct access to the parallel port, so be prepared to write a driver (very hard!). I have a PIC programmer that uses the parallel port, which doesn't work with Windows 2000/XP (now I found a use for the old laptop running Windows 98).
im sorry but i forgot to menchun i nead it to be portible thanks enyways, mabye i can youse my parralel port for somthing elts that doesnt nead to be portible
Then get one of those bike flashing lights and throw a decimal counter in there and wire the LEDs to that counter. Cheap and easy.
hey thats a good idea but as i am running it through my head it wouldnt work with what i am doing plus the minummum would have to be 5 leds and it wouldnt be random enough for what i am doing thanks enyways
