Thread: Why are four states needed with Quadratuer encoders?
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Unread 10-11-2005, 10:58
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Re: Why are four states needed with Quadratuer encoders?
Absolutely, you need to catch both the rising and falling edge.

If you watch only one edge,for the sake of argument let's use the rising edge (0->1) , you will only ever be looking at the following transitions...
00->01 00->10 01->11 10->11
Compare that to the table above and you'll see that you're only getting half the story. Watching only one edge will definately not work for the normal usage.