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Analog read of off-the-shelf potentiometer 
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Joined: Tue Sep 21, 2010 9:28 pm
Posts: 1
Post Analog read of off-the-shelf potentiometer
All of the online resources I have read indicate that a potentiometer on analog 1 should read about 5 to 4095 showing 12 bit resolution. Other sources indicate a 16 kHz
sample rate. I have an off-the-shelf potentiometer which is not a vex sensor. I have it set up in an analog sensor. When the pot is full
right and reads 0 on a meter, it shows 0 as a sensor value in the debug window of RobotC. However, when I turn the pot to the other side, it only reads 61. The sensor reading is
smooth and predictable, but the resolution is very coarse. I want to capture at least a half-degree resolution. I am using the black/white sensor plug and wiring it to the middle and outside leg of the potentiometer. Using the VEX potentiometer is not possible. Any suggestions?


Thu Oct 24, 2013 9:18 pm
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Joined: Thu Dec 01, 2011 12:07 am
Posts: 34
Post Re: Analog read of off-the-shelf potentiometer
The analog ports have 0V, 5V, and the input.
http://content.vexrobotics.com/docs/VEXnet_Cortex_UserGuide_081811.pdf
One side of the pot goes to 0V, the other goes to 5V, and the wiper goes to the analog input.
The pot should be 5K Ohm.
You should measure from 0V to 5V on the analog input with a DMM as you turn the pot.
Please provide a schematic and pot data if it still does not work.
Good luck!


Fri Oct 25, 2013 12:16 pm
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