Code:
' Process the fourth display
	If O_C=3 then				' If it is our turn then
	Digit2=0					' Turn OFF the third LED
If sign="-" then
        PortB=%00111111
        PortB.7=0
else
	PortB=Disp_Patt				' Place the digit pattern on portC
endif
	If DP=3 then PortB.7=0			' Check the value of DP and Turn ON the decimal point
	Digit3=1					' Turn ON the fourth LED
	Endif