Parallax Boe-Bot Student Manual page 311

intersection is a 3-way or 4-way intersection, the Boe-Bot will arbitrarily turn in
the direction that black is first detected. A constant,
to tune the 90 degree turn. Some audible and visual indicators are included,
which aid in troubleshooting and understanding what the Boe-Bot is seeing and
deciding, as well as adding a bit of personality and fun.
' -----[ Title ]-------------------------------------------------------
' Robotics with the Boe-Bot - IntersectionsBoeBot.bs2
' Navigate 90 degree left/right, 3-way, and 4-way intersections.
' Based on StripeFollowingBoeBot.bs2
' {$STAMP BS2}
' {$PBASIC 2.5}
DEBUG "Program Running!"
' -----[ Constants ]---------------------------------------------------
Kpl CON
Kpr CON
SetPoint CON
CenterPulse CON
Turn90Degree CON
RightLED PIN
LeftLED PIN
' -----[ Variables ]---------------------------------------------------
freqSelect VAR
irFrequency VAR
irDetectLeft VAR
irDetectRight VAR
distanceLeft VAR
distanceRight VAR
pulseLeft VAR
pulseRight VAR
numPulses VAR
fwdPulses VAR
counter VAR
isStuck VAR
' -----[ Initialization ]----------------------------------------------
FREQOUT 4, 2000, 3000
' -----[ Main Routine ]------------------------------------------------
DO
GOSUB Get_Ir_Distances
Chapter 8: Robot Control with Distance Detection · Page 297
' Stamp directive.
' PBASIC directive.
35 ' Left proportional constant
-35 ' Right proportional constant
3 ' 0-1 is White, 4-5 is Black
750
30 ' Pulses needed for 90 turn
1 ' LED Indicators
10
Nib ' Sweep through 5 frequencies
Word ' Freq sent to IR emitter
Bit ' Store results from detectors
Bit
Nib ' Calculate distance zones
Nib
Word ' Servo pulseWidths
Word
Byte ' Count total pulses
Byte ' Count forward pulses
Byte
Bit ' Boolean variable,is bot stuck?
' Read IR sensors
, is provided
Turn90Degree