Based on the signal from {HEAD ~ the difference integrating section}, {TAIL ~ the discriminating section} discriminates the authenticity, denomination and top or bottom surface of the bill 
Based on the signal from { HEAD ~ the difference integrating section } , { TAIL ~ the discriminating section } discriminates the authenticity , denomination and top or bottom surface of the bill
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH