Hi,
Yes of course, one edge.But if the interrupts are meant to fire on either a rising or falling edge, then going from '00' to '10' has only one edge (A rises from 0 to 1; B stays the same).
It depends on the encoder used but most mechanical type encoders I've come across has a full quadrature cycle per detent. Here's cutout from the datasheet for a EN12-series encoder from TT Electronics:The 00 to 10 state change represents one detent, right?
As you can see, going from one detent to the next results in a full quadrature cycle or four edges. So if the IOC is setup to trig the on the rising and falling edge of both the A and the B input then you'll have four interrupts per detent so the MotorRPM variable will increase by 4.
When it "seemed to work back then" was that with this very same encoder or have you changed it? Do you have a modelnumber or datasheet for the encoder you're using?
/Henrik.
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