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Diagnostic LEDs

The Cricket hardware has three LEDs, which you can use to infer a few things about the device's state. At startup, all the LEDs light up for 500 milliseconds. At run time the LEDs light up as shown in the following table:

LED Listener Beacon
Green (D3) lights up when a lights up for 150 microseconds
  valid RF chirp during ultrasound trasmission
  arrives from a beacon (may not be visible in bright light)
Red (D2) lights up when a lights up for 150 microseconds,
  collision occurs (e.g., due to hidden when the beacon fails to
  terminal or improper beaconing) grab a time slot to send a chirp
Yellow (D4) lights up when an Not used yet
  RF message is received  
  but with no ultrasonic pulse  


next up previous contents
Next: Test Switch Up: Cricket Hardware Details Previous: Cricket Hardware Details   Contents
Michel Goraczko 2004-12-02