Since today, no matter what program that uses sensors I try to run on my EV3 I get the following error:

lejos.hardware.DeviceException: unable to open port
    at lejos.internal.ev3.EV3Port.open(EV3Port.java:75)
    at lejos.hardware.sensor.AnalogSensor.<init>(AnalogSensor.java:24)
    at lejos.hardware.sensor.AnalogSensor.<init>(AnalogSensor.java:35)
    at lejos.hardware.sensor.EV3TouchSensor.<init>(EV3TouchSensor.java:61)
    at ia.Sensor.<init>(Sensor.java:19)
    at ia.Robot.<init>(Robot.java:16)
    at ia.Jeu.main(Jeu.java:16)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at lejos.internal.ev3.EV3Wrapper.invokeClass(EV3Wrapper.java:62)
    at lejos.internal.ev3.EV3Wrapper.main(EV3Wrapper.java:46)

I've checked the ports, the cables and my ultrasonic sensor (which seems to be where the problem is) but nothing. I get the same error when I try closing the sensor.

  • 4
    This is a stack trace. What is the actual error? Are you using LeJOS firmware or ev3dev-lang-java? Commented Dec 1, 2023 at 0:18
  • 1
    @DavidLechner Sorry, I didn't paste it correctly, it should appear now. I'm using ev3dev-lang-java.
    – celia
    Commented Dec 1, 2023 at 12:25
  • Do the sensors show up in the in the "Device Browser" on the EV3? Commented Dec 2, 2023 at 16:38


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