PICBasic firmware for PIC12F675

Define OSCCAL_1K 1  ' Calibrate internal oscillator
LED Con 0
ENAB Con 5
STOPPED Con 4
ANSEL = 0     ' Set all digital
CMCON = 7     ' Analog comparators off
OPTION_REG.7 = 0 ' Enable WPUs
Low LED
mainloop:
    ' loop while not enabled
    IF ENAB = 1 THEN
        GOTO mainloop
    ENDIF
    ' loop if car not stopped
    IF STOPPED = 1 THEN
        GOTO mainloop
    ENDIF
    Pause 500     ' Delay for .5 seconds
blinking:
    High LED
    Pause 300
    Low LED
    Pause 500
    ' car started moving, or green light disappeared?
    IF STOPPED = 1 OR ENAB = 1 THEN
        GOTO mainloop
    ENDIF
    GOTO blinking
End