[sdiy] Using an AT90S1200 as a triple DCO

[Paul Maddox]

Jarek,

> The micro DOES NOT generate square waves!
> Look at the schematic - the op-amps U4A, U4B, U4C act as comparators
> and compare the sawtooth waves from U3B, U3C, U3D to the CONTROL
> VOLTAGES held at their non-inverting inputs. These three op-amps are in
fact
> "sample & hold & compare" units.

<DOH>
my bad, not enough caffine!

> Generating additionally three pulse waveforms, each one with independent
> pulse width setting, would be definitely too much for that poor AT90S1200!

hehe.

Paul