Merge branch 'crawler-software'

crawler_software/arduino/crawler_slave/crawler_slave.ino

@@ -0,0 +1,63 @@
+/* Crawler Slave
+ *  
+ *  This code runs on the crawler i2c network
+ *  and provides a cleaner, less CPU intensive control over PWM devices.
+ */
+
+#include <Wire.h>
+#include <Servo.h>
+
+// This servo is used to wipe and clean the camera lens
+Servo windowWiperServo;
+
+// Variables populated over i2c from master
+int id;
+int val;
+
+void setup() {
+  // For debugging
+  //Serial.begin(115200);
+  
+  // Attach the wiper servo to pin 9
+  windowWiperServo.attach(9);
+
+  // This is the address the pi will speak to us at
+  Wire.begin(0x4);
+  
+  // Call receiveEvent when data received                
+  Wire.onReceive(receiveEvent);
+
+  // Setup LED
+  pinMode(LED_BUILTIN, OUTPUT);
+  digitalWrite(LED_BUILTIN, LOW);
+
+  //Serial.println("Started");
+}
+
+// Just loop to keep the running code alive, and wait for events to happen.
+void loop() {
+  delay(50);
+}
+
+// This method runs when we receive a message
+void receiveEvent(int n) {
+  Wire.read(); // Remove smbus trash
+  if (true) { // Dont do anything if this is not true
+    id  = Wire.read(); // ID of the servo/device to access
+    val = Wire.read(); // Value to assign
+
+    //Serial.println(id);
+    //Serial.println(val);
+  
+    switch(id) {
+      case 1:
+        windowWiperServo.write(val);
+        break;
+    }
+  }
+
+  // Prevents a bug where if bytes are left in buffer, arduino crashes.
+  while (Wire.available()) {
+    Wire.read();
+  }
+}