Merge pull request #325 from adafruit/TheKitty-patch-23

Create potentiometer-neopixels.ino

Make_It_Twist_Potentiometer/potentiometer-neopixels.ino

@@ -0,0 +1,55 @@
+// Read analog potentiometer on Circuit Playground Express or other board with changes
+// Mike Barela for Adafruit Industries 9/2018 based on
+// NeoPixel Ring simple sketch (c) 2013 Shae Erisson
+// released under the GPLv3 license to match the rest of the AdaFruit NeoPixel library
+
+#include <Adafruit_NeoPixel.h>
+#ifdef __AVR__
+  #include <avr/power.h>
+#endif
+
+// Which pin on the microcontroller board is connected to the NeoPixels?
+#define PIN             8  // For Circuit Playground Express
+
+// How many NeoPixels are attached to the board?
+#define NUMPIXELS      10
+
+// When we setup the NeoPixel library, we tell it how many pixels, and which pin to use to send signals.
+// Note that for older NeoPixel strips you might need to change the third parameter--see the strandtest
+// example for more information on possible values.
+Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, PIN, NEO_GRB + NEO_KHZ800);
+
+int delayval = 500; // delay for half a second
+
+void setup() {
+  Serial.begin(9600);
+  pixels.begin(); // This initializes the NeoPixel library.
+}
+
+void loop() {
+   int i;              // loop variable
+   int value;          // analog read of potentiometer
+   int display_value;  // number of NeoPixels to display out of NUMPIXELS
+
+   // Read PIN value and scale from 0 to NUMPIXELS -1
+   value = analogRead(A1);
+   Serial.print(value);
+   Serial.print(", ");
+   display_value = int(value  * NUMPIXELS / 1023);
+   Serial.println(display_value);
+
+   // For a set of NeoPixels the first NeoPixel is 0, second is 1, all the way up to the count of pixels minus one
+
+   for(i=0; i<display_value; i++){
+
+      // pixels.Color takes RGB values, from 0,0,0 up to 255,255,255
+      pixels.setPixelColor(i, 0, 050, 0); // Moderately bright green color
+   }
+   for(i=display_value; i<NUMPIXELS; i++) {
+      pixels.setPixelColor(i, 0, 0, 0);    // turn off all pixels after value displayed
+   }
+
+   pixels.show(); // This sends the updated pixel color to the hardware.
+
+   delay(delayval); // Delay for a period of time (in milliseconds).
+}