Agilent Technologies 83620B

870 P0=VAL(Power$)
880 Flips=0
890 Slope=0
900 REPEAT
910 OUTPUT @Meter;"TR2"
920 ENTER @Meter;Power$
930 P1=VAL(Power$)
940 Slope2=SGN(P0-P1)
950 IF Slope2Slope THEN
960 Flips=Flips+1
970 Slope2=Slope
980 ELSE
990 IF Slope2=0 THEN Flips=Flips+.2
1000 END IF
1010 P0=P1
1020 UNTIL Flips>=3
1030 Power=(P0+P1)/2
1040 RETURN Power
1050 FNEND
Getting Started Programming 1-105