> Assuming active-high outputs, with a 0% duty cycle, PA1 is off,
> P1B is on, and the motor spins one way.  At 100% duty cycle,
> the opposite is true.  A 50% duty cycle implies an alternating (but
> balanced) forward/reverse action

Oh, I see what you mean. But using two outputs of an L293 is
actually an H-bridge isn't it, as each output has a high- and low-side
transistor. What you're suggesting would be the same as alternately
turning on/off the (S1, S4) and (S2, S3) pairs of discrete switches.
/Enable =3D 0 of the L293 performs the same function as turning all
devices off in an H-bridge

As you say, the nett effect would be no movement although I suspect
there will be (quite) some heat to dissipate in the motor, as its=20
effectively
receiving full power. This wouldn't be good for a fan-cooled motor. And
perhaps heating also in the drivers if the noise generated and/or switching
waveforms stops them operating as the intended digital devices

Joe

--=20
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