28125 Parallax Inc, 28125 Datasheet - Page 279

• Manufacturer Part Number: 28125
• Description: TEXT ROBOTICS
• Manufacturer: Parallax Inc

Specifications of 28125

• Title: Robotics with the Boe-Bot
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Not applicable / Not applicable

P2. This behavior is in many ways the opposite of the roaming behavior covered in
' -----[ Main Routine ]------------------------------------------------
Main:
' Loop until something is detected
' Now start roaming -- this code from FastIrRoaming.bs2
' -----[ Subroutines ] ------------------------------------------------
Check_IRs:
this chapter. Instead of avoiding objects, the Boe-Bot tries to go toward the
objects.
"FastIrRoaming.bs2", with a bit added that spins the Boe-Bot slowly until an
object is detected.
In the solution below, once the Boe-Bot has spied an object, it will continue
forward even if the detectors both read "no object" (1) for a few loops. This is
because, as the Boe-Bot is maneuvering toward the object, sometimes the
DO
LOOP UNTIL (irDetectLeft = 0) OR (irDetectRight = 0)
DO
LOOP
FREQOUT 8, 1, 38500
irDetectLeft = IN9
FREQOUT 2, 1, 38500
IrDetectRight = IN0
RETURN
GOSUB Check_IRs
IF (irDetectLeft = 0) AND (irDetectRight = 0) THEN
ELSEIF (irDetectLeft = 0) THEN
ELSEIF (irDetectRight = 0) THEN
ELSE
ENDIF
PULSOUT 13, pulseLeft
PULSOUT 12, pulseRight
PAUSE 15
GOSUB Check_IRs
pulseLeft = 650
pulseRight = 850
pulseLeft = 850
pulseRight = 850
pulseLeft = 650
pulseRight = 650
pulseLeft = 850
pulseRight = 650
For this reason, the main code can be derived from
' Both detect
' Back up
' Left detect
' Turn right
' Right detect
' Turn left
' Nothing detected
' Go forward
' Apply the pulse.
' Check IRs again
' Check IR Detectors