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From: sburton@dres.dnd.ca (Stan Burton)
Subject: Re: How to control hobby servo with computer ????
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In article <C1zJD9.623@world.std.com> sja@world.std.com (Stuart J Adams) writes:
> How can I control hobby servos (i.e. the ones used for model planes/cars)
> with my computer ???  From what I remeber these things are +5 powered
> with a PWM signal for controling servo postion. Are there any chips
> to automate the control of servos so that my computer does not have to
> generate the PWM signal ???
>

Hobby servos require a PWM signal for position control.  The signal is a
5 volt positive pulse with a period of approximately 1 to 2 ms
depending on servo manufacturer (some spec it as 1.51 ms +/- 400 us).
Generating this with a PC can be a challenge if you want to do other
things with your PC.  I suggest a 68HC11 processor as a controller, it
is very well suited to this.  You can pass serial commands to the
68HC11 from your PC and guarantee that the timings will be right and
jitter free.

>
> Thanks,
> Stuart Adams
> sja@world.std.com

--

Stan Burton (DND/CRAD/DRES/DTD/MSS/AGCG)                 sburton@dres.dnd.ca
(403) 544-4737     DRE Suffield, Box 4000, Medicine Hat, AB, Canada, T1A 8K6
