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Can i control a servo with a 555 timer?


I would like to sweep a servo back and forth, and theres no point on using the arduino for this, and thats all i have at the moment, so if i supply 0v to the yellow wire on the servo(signal) and then supply it with 5v, then 0, then 5v again.... would it sweep the servo? or does it have to be modulated?



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Take a look at this page for information on how to control a servo.

A servo requires a pulsed signal, about one pulse every 20ms or faster for smooth movement. The width of the pulse, typically between 1 and 2ms at most, determines the angle the servo will go to. To make a servo sweep you need to feed the servo a series of pulses that becomes shorter and longer; shorter pulses make the servo go one way and longer pulses make the servo go the other way.
Although I'm sure there's a way to sweep a servo using a single 555, it's probably easier to use 2 555s. Have one 555 produce the standard neutral position pulse (1.25ms every 20ms), and then have the other 555 generate a slower signal that biases the first 555, making its pulses lengthen or shorten. As you can probably tell, this solution is already starting to get a bit complicated compared to just using an Arduino, but if you're really determined to do it this way then take a good look at the 555 datasheet and check out some recommended circuits.

yes, very complicated :P

 i guess i can use an attiny, i just dont know how to program those, other option is 8 pin picaxe, i have never used any of these, and cant really spend much dough on this right now... i will try using the 555's, whoknos, maybe even by modifying the servo internally?

The picaxe(08M) would be pretty simple(cheap,small) and you could do quite a bit with it as well if you wanted to expand on just simply rotating back and fourth...