On Thu, Sep 8, 2011 at 9:54 PM, David Duffy (AVD)
<david@audiovisualdevices.com.au> wrote:
> Josh, the basic idea is:
>
> Set up a free running 20ms timer on tmr0.
>
> When tmr0 fires, set the first servo output high and set tmr1 to the
> pulse width you want for servo 1.
>
> When tmr1 fires, turn servo output 1 off, turn servo 2 output on and set
> tmr1 to the pulse width you want for servo 2.
>
> Repeat unitl all servos are serviced, then wait for the 20ms timer to
> fire again.
>
> This round robin works for up to 8 servos as 8 x 2ms =3D 16ms so you can
> service them all within the 20ms. =A0The pulse positions move about
> somewhat within each 20ms event, but the servos don't seem to mind.

Ok, that's what I figured. Is there a clever way to save a timer and
integrate it all into one? That's where I was headed with my comments
before. I don't know if this is possible, but could you have say TMR3
generating the 20mS interrupt, then use the CCP module on TMR3 to
generate the pulse width? I haven't had the time to do the math to see
if that would work, but I have no idea if it's even within the realm
of possibility.

Thanks!

Josh
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