Multiple measurements

The library will not automatically perform multiple measurements on a sensor (Ex: To resolve for instance Detect Integration or recalibration.). The user is given the option to perform the measurement multiple times if certain conditions are met. This will enable the user to implement the time critical code thereby making the qt_measure_sensors() a non-blocking API .The host application has to perform multiple measurements, based on the need. The global flag QTLIB_BURST_AGAIN indicating that multiple measurements are needed is passed to the user. This is BIT8 of the return value from the qt_measure_sensors( ) API. The main_<devicename>.c has the example usage to perform multiple measurements.

If QTLIB_BURST_AGAIN = 1, multiple measurements are needed to

  1. 1.

    To compensate for drift

  2. 2.

    Resolve re-calibration

  3. 3.

    Resolve calibration.

  4. 4.

    Resolve detect integration.

If QTLIB_BURST_AGAIN = 0, multiple measurements are not needed and the user can execute the host application code. Apart from QTLIB_BURST_AGAIN, various flags are provided to the user to perform the multiple measurements based on the need of the host application to act to specific situation. Description of the these flags can be found in QTouch API and Usage

Note: To maintain robustness and timing of the touch sensing measurement, it is recommended that the user calls the qt_measure_sensors() immediately if the flag QT_BURST_AGAIN=1. However, the user is allowed to run time- critical section (not more than few instructions) of the host application comprising on the touch sensing timing.