Few thoughts...
- If you have the PIC set for pot use and connect the encoder instead,=20
you may have a situation where you're forcing an encoder output to high=20
and perhaps cause a short.
- Doesn't the encoder need pull-up resistors, and if so, does the analog=20
input you're using also have internal weak pull-ups?
- If you have spare pins, perhaps send the encoder outputs to two=20
separate pins for simplicity?
- A high output doesn't go all the way to Vdd, so your A/D conversion=20
may not reach full scale if you're using the internal (Vdd) reference. =20
You can compensate for that in code.

Cheers,
-Neil.




On 3/18/2017 11:24 AM, Josh Koffman wrote:
> Hi all,
>
> I've got to say, I'm having a lot of fun on this little dimmer project
> of mine. Trying to cram as many options and possibilities into a tiny
> space is intriguing!
>
> My latest idea involves the control. I had originally planned on using
> a pot to control the dimmer. But with a bit of searching I've found a
> pot and an encoder with similar enough footprints that with a bit of
> tweaking I'd be able to fit either on the board. For those curious,
> the pot is the P0915N-FC15BR10K and the encoder is the EN11-HSM1BF20 ,
> both from TT Electronics.
>
> My original plan was to use a bunch of resistors as jumpers and load
> the board depending on which controller was installed. Then I got to
> thinking...(uh oh...).
>
> Each device has three pins. On the pot, 1 and 3 are the sides of the
> resistor, and 2 is the wiper. On the encoder, pins 1 and two are the
> outputs, and 2 is the common. What I'm thinking about doing is
> connecting all three to the PIC, with pin 2 being an analog input
> capable pin. For pot use, I'd set pin 1 and 3 as outputs, and set 1
> high, and pin 2 as an analog input. For encoder use, I'd set pin 2 as
> an output and set it low. Then set pins 1 and 3 as inputs with weak
> pull ups and read away.
>
> Thoughts? Pitfalls? Trying for the lowest parts design to save space!
>
> Josh
>
>
>
>

--=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
.