Added protothread arduino library

arduino/libs/ArduinoThread/Thread.cpp

@@ -0,0 +1,52 @@
+#include "Thread.h"
+
+Thread::Thread(void (*callback)(void), unsigned long _interval){
+	enabled = true;
+	onRun(callback);
+	_cached_next_run = 0;
+	last_run = millis();
+
+	ThreadID = (int)this;
+	#ifdef USE_THREAD_NAMES
+		ThreadName = "Thread ";
+		ThreadName = ThreadName + ThreadID;
+	#endif
+
+	setInterval(_interval);
+};
+
+void Thread::runned(unsigned long time){
+	// Saves last_run
+	last_run = time;
+
+	// Cache next run
+	_cached_next_run = last_run + interval;
+}
+
+void Thread::setInterval(unsigned long _interval){
+	// Save interval
+	interval = _interval;
+
+	// Cache the next run based on the last_run
+	_cached_next_run = last_run + interval;
+}
+
+bool Thread::shouldRun(unsigned long time){
+	// If the "sign" bit is set the signed difference would be negative
+	bool time_remaining = (time - _cached_next_run) & 0x80000000;
+
+	// Exceeded the time limit, AND is enabled? Then should run...
+	return !time_remaining && enabled;
+}
+
+void Thread::onRun(void (*callback)(void)){
+	_onRun = callback;
+}
+
+void Thread::run(){
+	if(_onRun != NULL)
+		_onRun();
+
+	// Update last_run and _cached_next_run
+	runned();
+}