add gain=2, non-blocking operation, led abstracted

Metro.h

@@ -0,0 +1,49 @@
+
+/*
+ *      This program is free software; you can redistribute it and/or modify
+ *      it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 of the License, or
+ *      (at your option) any later version.
+ *      
+ *      This program is distributed in the hope that it will be useful,
+ *      but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *      GNU General Public License for more details.
+ *      
+ *      You should have received a copy of the GNU General Public License
+ *      along with this program; if not, write to the Free Software
+ *      Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ *      MA 02110-1301, USA.
+ */
+
+
+
+/*  * * * * * * * * * * * * * * * * * * * * * * * * * * * 
+ Main code by Thomas O Fredericks (tof@t-o-f.info)
+ Contributions by Paul Bouchier and Benjamin.soelberg
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+#ifndef Metro_h
+#define Metro_h
+
+#include <inttypes.h>
+
+
+class Metro
+{
+
+public:
+  Metro();
+  Metro(unsigned long interval_millis);
+  void interval(unsigned long interval_millis);
+  uint8_t check();
+  void reset();
+	
+private:
+  unsigned long  previous_millis, interval_millis;
+
+};
+
+#endif
+
+