Create/modify read string code

crawler_software/arduino/crawler_slave/crawler_slave.ino

@@ -10,16 +10,23 @@
 // This servo is used to wipe and clean the camera lens
 Servo windowWiperServo;
 
+// This is a variable capable of storing up to 4 items
+char instruction[4] = "";
+
 void setup() {
   // Attach the wiper servo to pin 9
   windowWiperServo.attach(9);
 
+  // This is only useful for debugging
+  Serial.begin(9600);
+
   // This is the address the pi will speak to us at
   Wire.begin(0x8);
   
   // Call receiveEvent when data received                
   Wire.onReceive(receiveEvent);
-  
+
+  Serial.print("Finished Setup.");  
 }
 
 // Just loop to keep the running code alive, and wait for events to happen.
@@ -28,9 +35,11 @@ void loop() {
 }
 
 // This method runs when we receive a message
-void receiveEvent(int howMany) {
-  while (Wire.available()) { // loop through all but the last
-    int pos = Wire.read(); // receive byte as a int
-    windowWiperServo.write(pos);
+void receiveEvent(int n) {
+  for (int i = 0; i < n; i++) //n is equal to the number of data bytes received
+  {
+    instruction[i] = Wire.read();
   }
+  
+  Serial.print(instruction);
 }