 OWI owi(Board::D1);
 #else
 OWI owi(Board::D7);
+#define USE_RTC
+#endif
+
+#ifdef USE_RTC
+#include "Cosa/TWI/Driver/DS1307.hh"
+DS1307 rtc;
+time_t now;
 #endif
 
 // Simple alarm callback handler


void loop()
{
  // Issue a convert request and check for alarms
  ledPin.toggle();
  DS18B20::convert_request(&owi, 12, true);
  owi.alarm_dispatch();
  ledPin.toggle();
  SLEEP(1);
}

 * pin(D7). They may be in parasite power mode.
 *
 * Note that temperature is only read on an alarm. A conversion
 * request is issued every 2 seconds. The request is boardcasted to all
 * connected devices (i.e. a single command is sent without rom
 * address).
  *
