Started following some tutorial on att85 usi. Downloaded example code from make avr book.

Make AVR Examples/Chapter05_Serial-IO/serialOrgan/organ.h

@@ -0,0 +1,9 @@
+
+// ------------- Function prototypes -------------- //
+
+// Plays a note for the given duration.  None of these times are
+//  calibrated to actual notes or tempi.  It's all relative to TIMEBASE.
+void playNote(uint16_t period, uint16_t duration);
+
+// Does nothing for a time equal to the passed duration.
+void rest(uint16_t duration);