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Unread 10-11-2017, 06:32 PM
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Question on CIMcoder codes per rev

I was curious as to what the codes per revolution were for the CIMcoder. Trying to look through the documentation and it looks like it should be 20, but I wanted to make sure. Thanks!
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Unread 10-11-2017, 06:39 PM
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Re: Question on CIMcoder codes per rev

According to the AndyMark product page, the CIMcoder has a resolution of 20 PPR (pulses per revolution). Since it's a quadrature encoder, that gives it a CPR (counts per revolution) of 20*4=80. I've never heard of "codes per revolution", but I'm assuming its equivalent to one of those two. There's a decent explanation of the definition of each here.
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Unread 10-11-2017, 06:46 PM
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Re: Question on CIMcoder codes per rev

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Originally Posted by AriMB View Post
According to the AndyMark product page, the CIMcoder has a resolution of 20 PPR (pulses per revolution). Since it's a quadrature encoder, that gives it a CPR (counts per revolution) of 20*4=80. I've never heard of "codes per revolution", but I'm assuming its equivalent to one of those two. There's a decent explanation of the definition of each here.
Edit: Upon searching past threads, this actually appears to be used both ways - CPR can refer to individual counts, or to entire cycles. Huh. That's a possible spot for confusion.
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Last edited by Oblarg : 10-11-2017 at 06:58 PM.
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Unread 10-11-2017, 06:59 PM
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Re: Question on CIMcoder codes per rev

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Originally Posted by Oblarg View Post
You have that backwards. PPR=4*CPR for a quadrature encoder. There are four pulses per cycle.
At first I only saw sources saying what I originally said, but now I am seeing sources for both directions. I remember this being a very confusing and controversial topic in the past. Basically, it seems like different companies are using the same words to mean different things, often without explaining which definitions they are using.

Sources my way:
https://granitedevices.com/wiki/Quadrature
http://www.cui.com/blog/what-is-encoder-ppr-cpr-and-lpr

Sources your way:
http://encoder.com/glossary-of-terms/
https://www.usdigital.com/support/glossary

ChiefDelphi argument:
https://www.chiefdelphi.com/forums/s....php?p=1604976

I still have yet to see "codes per revolution" in any of these search results, so I'm interested in hearing what the OP meant by that.
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Unread 10-13-2017, 10:10 AM
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Re: Question on CIMcoder codes per rev

codes per revolution actually came from the talon srx library. When setting up the talon object, there is a parameter called configEncoderCodesPerRev when using a quad encoder.

Thanks for the feedback everyone, I appreciate it
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