;--------------------------------------------------------------------------
;				Cmd 0 / Arpeggio
;--------------------------------------------------------------------------

Input:		Counter
			n_period
			
Output:		SampPer

Counter % 3 = 0: SampPer := n_period
Counter % 3 = 1: SampPer := n_period + halfnotes1
Counter % 3 = 2: SampPer := n_period + halfnotes2

