BMP180 data logging errors


#1

Hi,
I’ve been running a BMP180 on an Arduino Uno for several weeks and noted a significant logging fault. Very often at the top of the hour, the data trace will either increase (mostly) or decrease (occasionally), giving an erroneous value. I have used the serial output to confirm that the data from the BMP180 is constant, and it is. I didn’t expect any error here because neither the sensor or the Arduino are locked to a RTC, so there is no way the device can be aware of the real time. The problem affects the hour log and the day log and the week log because the the hourly values are carried across to the next logging page. I have a large number of screen shots, but will limit my post to a few temp and pressure images. BTW this anomaly affects both PC web based views and Android app images.



Note in these two shots that the actual atmospheric pressure is under 1000hPa, but because of the spike at 1pm, the weekly log shows the pressure much higher than the actual, so a momentary error is moving into a long-term problem.



These two temperature plots also show how the error is migrated from one group to the next, in this case, from hours to days.

I have MANY more screen shots if needed

I hope the bug can be resolved.
Cheers,
Brian