Robotics with the Boe-Bot text v2.2

Chapter 7: Navigating with Infrared Headlights · Page 259
FREQOUT 4, 2000, 3000 ' Signal program start/reset.
DO ' Main Routine.
FREQOUT 8, 1, 38500 ' Check IR detectors.
irDetectLeft = IN9
FREQOUT 2, 1, 38500
irDetectRight = IN0
' Decide navigation.
IF (irDetectLeft = 0) AND (irDetectRight = 0) THEN
pulseCount = 1 ' Both detected,
pulseLeft = 850 ' one pulse forward.
pulseRight = 650
ELSEIF (irDetectRight = 1) THEN ' Right not detected,
pulseCount = 10 ' 10 pulses left.
pulseLeft = 650
pulseRight = 650
ELSEIF (irDetectLeft = 1) THEN ' Left not detected,
pulseCount = 10 ' 10 pulses right.
pulseLeft = 850
pulseRight = 850
ELSE ' Neither detected,
pulseCount = 15 ' back up and try again.
pulseLeft = 650
pulseRight = 850
ENDIF
FOR loopCount = 1 TO pulseCount ' Send pulseCount pulses
PULSOUT 13,pulseLeft
PULSOUT 12,pulseRight
PAUSE 20
NEXT
LOOP
How AvoidTableEdge.bs2 Works
Since this program is a modified version of FastIrRoaming.bs2, only changes to the program
are discussed here.
A FOR…NEXT loop is added to the program to control how many pulses are delivered each
time through the main (DO…LOOP) routine. Two variables are added, loopCount
functions as an index for a FOR…NEXT loop and pulseCount is used as the
EndValue
argument.
loopCount VAR Byte