rotary encoder question

[aballen]

I'm trying to figure out what type of rotary encoder this is.(does it put out grey code, 2-bit or 3-bit)

I'm looking at the Alps EC11B and Alps EC11E.

http://www.alps.com/WebObjects/catalog.woa/E/HTML/Encoder/Incremental/EC11/EC11_list.html

Kind of a long story, I'd be happy to provide more details if someone thinks they can assist.

[RobA]

From the output waveform in the doc, it looks like it's an incremental quadrature encoder.

[aballen]

ok, so I bought these, will these do ?

http://www.ebay.com/itm/160903297812?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

Trying to put together a pedal with a BTSE-99FX.  I have shift registers, most of the digital stuff is pretty straightforward, but I'm new to rotary encoders.  Appreciate the assist.

[RobA]

I found a schematic on their website for the effects unit. But, it's pretty blurry and it doesn't have a lot of info. So, I can't really be sure, but I'd guess that those encoders are going to be OK. The say they are two bit Gray code. That matches up with a standard quadrature encoder output and is pretty standard for use with microcontrollers. The reason is that the Gray code is setup to only have one bit change at each increment and this eliminates erroneous states that would occur using something like a straight binary representation.

Different encoders can have different numbers of detents and transitions per turn and per detent. They can also have the detents in different places on the output of the bits. That might have some influence on how the programs change, but I'd guess that it'll still work. The software probably just uses the output to determine which direction you are turning the knob and maybe how fast. That'll work with most any quadrature output encoder.

I assume that the switch on the schematic and the one on the encoder you ordered are both momentary. Neither of the docs say so, but it would be the normal thing for both of them really.

[aballen]

thanks, I'll give it a go.

accutronics sent me the alps rotary encoder, so it looks like I bought something similar enough.