IMU shield ADC misbehavior

My friend and I just received another IMU shield today, but I'm getting strange values from the ADC with APM_ADC_test:

ArduPilot Mega ADC library test

When running the same code with our working shields, we get numbers in the thousands that respond to rotational and acceleration movements.  The numbers on the new shield do not change regardless of inertial input.  I have tried r473 and r39 of the APM_ADC library (thinking maybe something got messed up recently), but they yield the same results.  The APM_BMP085 example runs fine on the new shield, and I can get the pressure & altitude values to change by blowing on the sensor.  I haven't had a chance to check the RC functionality.

In the unlikely event that it's helpful, the number below ADS7844N on one of the working shields is either 030G or 0306.  The number below the ADS7844N on the new shield is 0461.

Any ideas on what might be going on here?  Did we get a bad board?

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  • Developer
    Benjamin, maybe is a defective board... We test every board before shipping, but we may missed that one...
  • Admin

    What version of the IMU Mega Shield do you have? The original Foxtrap (F) or the new Hotel (H). It would help Jordi to know.

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