Can I operate a servo without an Arduino?

I just want to open the flush valve on a toilet and flush a toilet automatically on a timer once a day. I plan to use a servo (HS-322HD) to pull open the flush valve and, after a few seconds, release it. Using an Arduino microprocessor seems like overkill to me. Can I operate a servo just using 6vdc on/off signal or does it have to be a PWM signal?

With a little hacking, the below might work.


The usual solution is to use a 555 timer to create the variable pulses to drive a servo. Here's a schematic:

Thanks to Steve Walz for hosting all that stuff...

As your applications have the following requirements:

Continuously generate the servo flush valve closed position (1msec/50Hz pulse train)
Timer to initiate the once a day start flush signal
Generate the servo flush valve open position (2msec/50Hz pulse train) for a proper duration say 5 seconds.
Generate the servo flush valve closed position.
Restart the 24 hour timer.

I would suggest a arduino board of some kind is a simple and cost effective solution. If costs are important then a low cost E-bay Nano 'compatible' arduino board might be considered.


Thanks guys! I think I will go with Lefty's suggestion and buy a cheap Nano at about the same price as just a timer. It's not what I originally asked for, but it will give me great flexibility and the Nano could be used for other things. I didn't realize you can get so much power for only ten bucks.