"Smoke testing my pot": Reading serial data from a 10K linear sliding potentiometer via Arduino.

gistfile1.txt

More information on using pots with Arduino:
http://www.arduino.cc/en/Tutorial/Potentiometer

pot.pde

/*
  Analog input, analog output, serial output
 
 Reads an analog input pin, maps the result to a range from 0 to 255
 and uses the result to set the pulsewidth modulation (PWM) of an output pin.
 Also prints the results to the serial monitor.
 
 The circuit:
 * potentiometer connected to analog pin 0.
   Center pin of the potentiometer goes to the analog pin.
   side pins of the potentiometer go to +5V and ground
 * LED connected from digital pin 9 to ground
 
 created 29 Dec. 2008
 Modified 4 Sep 2010
 by Tom Igoe
 
 This example code is in the public domain.
 
 */

// These constants won't change.  They're used to give names
// to the pins used:
const int analogInPin = A0;  // Analog input pin that the potentiometer is attached to
const int analogOutPin = 13; // Analog output pin that the LED is attached to

int sensorValue = 0;        // value read from the pot
int outputValue = 0;        // value output to the PWM (analog out)

void setup() {
  // initialize serial communications at 9600 bps:
  Serial.begin(9600); 
}

void loop() {
  // read the analog in value:
  sensorValue = analogRead(analogInPin);            
  // map it to the range of the analog out:
  outputValue = map(sensorValue, 0, 1023, 0, 255);  
  // change the analog out value:
  analogWrite(analogOutPin, outputValue);           

  // print the results to the serial monitor:
  Serial.print("sensor = " );                       
  Serial.print(sensorValue);      
  Serial.print("\t output = ");      
  Serial.println(outputValue);   

  // wait 100 milliseconds before the next loop
  // for the analog-to-digital converter to settle
  // after the last reading:
  delay(100);                     
}

read-from-pot.js

// read-from-pot.js
// Jason Huggins (@hugs)
// License: WTFPL ( http://sam.zoy.org/wtfpl/ )

// Setup:
//   Buy an Arduino and install the Arduino IDE
//   Upload pot.pde to Arduino
//
//   Install node and npm
//   $ npm install serialport
//   $ node read-from-pot.js

// Example terminal output:
//   $ node read-serial.js
//   sensor = 0	    output = 0
//   sensor = 65    output = 16
//   sensor = 267   output = 66
//   sensor = 464   output = 115
//   sensor = 589   output = 146
//   sensor = 1023  output = 255
//   sensor = 1023  output = 255
//   sensor = 1022  output = 254

var sys = require('sys');
var serialport = require("serialport");
  
var sp = new serialport.SerialPort("/dev/cu.usbserial-A4001ubI", { 
    baudrate: 9600,
    parser: serialport.parsers.readline('\n')
});

sp.on("data", function (data) {
    sys.puts(data);
});