Saturday, September 16, 2017

Solving sensors communication errors

Dealing with sensors communication errors

  There are situations when after configuring one or more sensors embedded inside a SensorTag, on the main user interface:
  1. the information presented "freezes" (from one or more configured sensors) – e.g. does not change its value, while the information from other sensors is displayed correctly, or
  2. even we activated correctly a sensor, the associated controls are dimmed – on the blessTags user interface a control is dimmed only when: (a) the related sensor is invalidated and do not send data to the blessTags application or when (b) that sensor is not embedded on the SensorTag.
 Even if it looks surprising, the problem is the low battery level. Previously I said surprisingly because the battery level can be, for example, 67% or even 71% - the value displayed on the user interface for CC2650STK SensorTag. By replacing the battery with a new one, you will notice that all the problems listed above will disappear. I suspect that these false levels, of battery power, are due to a problem with the battery state measurement algorithm for CC2650STK (at least in the Firmware version 1.40).
 If the same battery is measured on a ThunderBoardSense SensorTag, battery power levels are much lower, somewhere in the 5 - 12% range.
 To prove all the statements presented previously, please view the movie below.