I've used the cheap eBay encoders Bob mentions, they output the full range of codes between detents which came as quite a surprise to me and took a little time to figure out when my code didn't appear to be working as expected. Of course there was no data sheet to reference so I assumed the first out of the pack was faulty, when I got to the third I had to accept that I'd misunderstood something and ordered a slightly more expensive branded part from a local supplier. Which did exactly the same thing. So it appears a lot of the cheaper detented encoders output all codes between detents, still useful but something to be aware of. The Bournes optical ones I'm using now are considerably more expensive but have no detent and make for a delightful VFO control input. On 6 Apr 2017 6:13 am, "Bob Blick" wrote: > Hi Sean, > > Those Grayhill ones definitely don't qualify as cheap :) > > The ones I use are like this: > > http://www.ebay.com/itm/-/311716200695 > > Although I usually pay about $0.40 each for them. > > Friendly regards, > > Bob > > ________________________________________ > From: piclist-bounces@mit.edu on behalf of Sean > Breheny > Sent: Wednesday, April 5, 2017 9:05 PM > To: Microcontroller discussion list - Public. > Subject: Re: [EE] Incremental Encoders > > Hmm, I used the Grayhill 61C series in a project and it had detents at ea= ch > quadrature position. I thought that this was standard when detents were > used. > > On Wed, Apr 5, 2017 at 6:54 PM, Bob Blick wrote: > > > Hi Phil, > > > > The typical cheap ones have detents in the "both switches off" position= .. > > As you move from detent to detent you get a full quadrature cycle, the > > outputs sequentially connecting to common in an order depending on whic= h > > direction you are turning. > > > > They are simple mechanical devices so they bounce and glitch just like > any > > cheap switch. You can hold them(and even balance them) in between > detents. > > Since the ones I use a cheap little things, the exact state while > > in-between is not really defined. But pretty much you can count on both > > outputs being open when within a detent. > > > > I decode them so that a single increment or decrement only happens upon > > both switches opening. Getting maximum resolution (X4) is not reasonabl= e > or > > desirable on these type of encoders. > > > > Cheerful regards, Bob > > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .