[sdiy] SAW core VCO flyback time

[David G Dixon]

> However, any 
> sub-oscillator divider that triggers off either edge would 
> suffer some pitch modulation.  I guess the easiest way to 
> mitigate this would be to just drive the sub-osc divider from 
> whatever logic in the tri-core that periodically switches the 
> direction of integration.

Yes, that's how we handle it in the Atlantis and the Dixie II+.  With a
tri-square oscillator, there is a perfect square wave available for this.