commit 1f4c87b09cfb0bd4ac0ce2878f9d79b7d3e7be25
Author: James <j@j-w.co>
Date:   Thu Nov 29 13:59:16 2018 +1100

    Create VU.ino

diff --git a/VU.ino b/VU.ino
new file mode 100644
index 0000000..8bee761
--- /dev/null
+++ b/VU.ino
@@ -0,0 +1,55 @@
+const int sinePin = 3;
+const int randomPin = 5;
+const int serialLedPin = 6;
+//pins 3, 5, 6, 9, 10, and 11
+const int maxOutputVoltage = 3;
+const int maxBright = 51 * maxOutputVoltage; //51 is ~1v
+const int minBright = 0;
+const int sinePeriod = 3;
+const int randomPeriod = 1;
+const bool debug = false;
+
+unsigned long randomLastRunMillis = 0;
+
+void setup() {
+  Serial.begin(115200);
+  pinMode(sinePin, OUTPUT);
+  pinMode(randomPin, OUTPUT);
+  pinMode(serialLedPin, OUTPUT);
+}
+
+void loop() {
+  int currentSecond = millis() / 1000;
+  analogWrite(sinePin, calculateSine());
+  if(millis() - randomLastRunMillis > (randomPeriod * 1000)) { analogWrite(randomPin, calculateRandom()); };
+  if(Serial.available() > 0) { analogWrite(serialLedPin, map(grabSerial(), 0, 100, minBright, maxBright)); };
+}
+
+int calculateSine() {
+  double tempMillis = millis();
+  double seed = (tempMillis / (1000.0 * sinePeriod)) * 2.0 * PI;
+  int outputValue = (sin(seed) - (-1)) * (maxBright - minBright) / (1 - (-1)) + minBright;
+  return outputValue;
+}
+
+int calculateRandom(){
+  randomLastRunMillis = millis();
+  int randomBrightness = random(minBright, maxBright);
+  if (debug) Serial.println(randomBrightness);
+  return randomBrightness;
+}
+
+int grabSerial(){
+  String incomingString;
+  while (Serial.available() > 0) {
+    char incomingByte = Serial.read();
+    if (debug) Serial.println(incomingByte, DEC);
+    if (incomingByte != 0x13) { //carriage return
+      incomingString.concat(incomingByte);
+    } else {
+      Serial.flush();
+    }
+  }
+  if (debug) Serial.println("I received: " + incomingString);
+  return incomingString.toInt();
+}