Rotary encoders

LoPP · Guest

Hello,

What type of rotary encoders can we connect to a PICmicro: TTL or HTL. Can we connect it directly or via a special device?

Regards

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

Here's how to find the information:

Look on Microchip's motor control web page. Look at their suggested
solutions, based on your type of motor (you didn't post your motor type):
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=2125&param=en026178

Look on the Microchip Part Selector page. Set the chip type to 18F.
Then set the number of QEI (Quadrature Encoder Interface) channels to
1 minimum and 2 maximum.
http://www.microchip.com/maps/microcontroller.aspx
You will get 4 results:

asmboy · Joined: 20 Nov 2007 Posts: 2128 Location: albany ny

About a year ago I did a rotary encoder interface that just uses a couple of B port lines - inplementing the interrupt on change function - and from inside the ISR, doing "state machine" comparisons - then outputting data as a +/- integer.

This is useful for relatively low update rates applicable to a manually turned shaft - and would crap out if the encoder is on a high RPM motor shaft. Would be fine for a human with a knob in their fingers though.

Ttelmah · Guest

Some time ago, I posted some parts of a quadrature decoder code, using INT_RB, and a high speed handler for the quadrature interrupt. This handled 'edge' rates up to quite a few 10's of KHz. Was used with a 256 line encoder, at over 5000RPM OK. Was posted here, so should be findable with a search.

Best Wishes