Added possible boot watcher

hardware/arduino/avr/libraries/Bridge/examples/BootWatcher001/BootWatcher001.ino

@@ -0,0 +1,90 @@
+
+/*
+  Arduino Yun Boot watcher
+ 
+ Allows you to use the Yun's 32U4 processor as a
+ serial terminal for the linino processor
+ 
+ Upload this to an Arduino Yun via serial (not WiFi) 
+ then open the serial monitor at 115200 to see the boot process
+ of the linino processor. You can also use the serial monitor
+ as a basic command line interface for the linino processor using 
+ this sketch.
+ 
+ The circuit:
+ * Arduino Yun
+ 
+ created March 2013
+ by Massimo Banzi
+ modified 26 May 2013
+ by Tom Igoe
+ 
+ This example code is in the public domain.
+ */
+
+long baud = 115200;
+
+// Pin 13 has an LED connected on most Arduino boards.
+// give it a name:
+int led = 13;
+int ledState = HIGH;   // whether the LED is high or low      
+
+String bootString = "";
+int bootLineCount = 0;
+boolean booting = true;
+
+void setup() {
+  Serial.begin(baud);        // open serial connection to Linino
+  Serial1.begin(baud);       // open serial connection via USB-Serial
+
+  // initialize the digital pin as an output.
+  pinMode(led, OUTPUT);    
+  digitalWrite(led, ledState);   // turn the LED on (HIGH is the voltage level)
+  while(booting) {
+    listenForBoot();
+  }
+  delay(500);
+}
+
+
+void loop() {
+  // After booting, become a serial terminal:
+  if (Serial.available()) {           // got anything from USB-Serial?
+    char c = (char)Serial.read();     // read from USB-serial
+    Serial1.write(c);                 // write to Linino
+    ledState=!ledState;               // invert LED state
+    digitalWrite(led, ledState);      // toggle the LED
+  }
+  if (Serial1.available()) {          // got anything from Linino?         
+    char c = (char)Serial1.read();    // read from Linino  
+    Serial.write(c);                  // write to USB-serial
+  }
+
+}
+
+void listenForBoot() {
+  char c;
+  if (Serial1.available()) {     // got anything from Linino?         
+    c = (char)Serial1.read();    // read from Linino  
+    
+    if (c == '\n') {             // clear the bootString every newline
+      bootLineCount++;                // increment the boot line counter
+      Serial.println(bootLineCount);  // print the count
+      bootString = "";           // clear the boot string
+    } 
+    else {                       // anything other than newline, add to string
+      bootString += c;
+    }
+  }
+
+  // look for the final boot string message:
+  if (bootString.endsWith("entered forwarding state")) {
+    Serial1.println(); 
+  }
+
+  // look for the command prompt:
+  if (bootString.endsWith(":/#")) {
+    Serial.println("Ready for action.");
+    booting = false;
+  }
+}