Skip to main content

Reply to "Recommendation for a Potentiometer with Stops (Detents)"

You could use the single output pin method driving 3 cascaded CD4026.  That is, you have a 3-digit decade counter that counts 000...999 by using the carry-out pin to drive the clock of the next counter.  Can get a bit messy since changing just the left-most digit involves sending 100 (to increment) or 900 (to decrement) clock pulses!  Changing just the right-most digit (without affecting the other digits) can get interesting too!  But it does meet the single-output pin criteria.  Obviously you could set up the 3 displays as 3 independent CD4026s but that would require 3 output pins.

So in this example the shift-register method might make more sense.  That is you cascade 3 74AC164 serial-in, parallel-out registers to create a 24-bit output.  You always need to send exactly 24 Morse-code pulses to change any display.  But it does meet the single-output pin criteria.

To your point, if the box is 10 feet away, having a separate Arduino becomes attractive.  As I recall there was angst in reliably decoding the analog voltage from the potentiometer using an A/D input of the Arduino.  Having that analog voltage run 10 feet down a cable would not help matters!

OGR Publishing, Inc., 1310 Eastside Centre Ct, Suite 6, Mountain Home, AR 72653
800-980-OGRR (6477)
www.ogaugerr.com

×
×
×
×
×