In SX Microcontrollers, SX/B Compiler and SX-Key Tool, JJHawg wrote:

Back to your last question Sean...

I haven't wired this up to test it, but you might be able to "matrix" the pots.

Consider 8 pots with one end of the resister tied to ground, and the other end tied to 1 of 8 port pins.  The wipers are all tied together and connected to a single ADC input.  Turn the pots on one-at-a-time with a "high" output the desired port pin and read the voltage on the ADC.

Of course this won't work because the other pots are in parallel an mess things up.  So, maybe a forward biased diode between each wiper connnection and the common ADC input would isolate each one, just like when using switch matrices.

There are a few things to consider with this experiment.  The exact voltage you read will be influenced the the voltage of the "high" port pin, and the characteristics of the diode.  There are some workarounds for this, but given your application these limitations might not matter.

For your matrix effect create 8 of these things, each set with its common wiper connection going to a different input on and 8 input ADC, and each pot of a "set" connected to the same "selecting" port pin.

I'm not sure how well this would work, but it sounds like you are really just having fun building it, so try it out...

My $0.02

Jim

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