SLAA877 December   2018 MSP430FR2633

 

  1.   Capacitive Touch Gesture Software and Tuning
    1.     Trademarks
    2. 1 Introduction
    3. 2 Gestures
      1. 2.1 Theory of Operation
      2. 2.2 Sensor Gesture Processing
      3. 2.3 Gesture Software Overview
        1. 2.3.1 Slider Gesture
        2. 2.3.2 Wheel Gesture
        3. 2.3.3 Button Gesture
        4. 2.3.4 Sensor Handlers
        5. 2.3.5 How to Add Gestures to the CapTIvate Framework
    4. 3 Tuning
      1. 3.1 CapTIvate Design Center
        1. 3.1.1 Enabling Gesture Sensor Output
        2. 3.1.2 CDC Plot Channel Assignments
      2. 3.2 Tuning Process
        1. 3.2.1 Tap
        2. 3.2.2 Double Tap
        3. 3.2.3 Swipe
        4. 3.2.4 Slide
    5. 4 Example Demonstration Software Installation
      1. 4.1 Project Directories
      2. 4.2 Import the Project Into CCS

3.2.1 Tap

The tap gesture is controlled by two timing parameters: ui16TouchSampleCount_Min and ui16TouchSampleCount_Max. The data channels used for Tap tuning are (000) finger touch, (001) sample count and (002) Tap gesture detect.

Figure 5 shows a valid tap gesture. When the finger touches, the sample count resets to zero then is incremented after each sensor measurement. The finger touches for 10 samples, meeting both the minimum and maximum timing parameters. A valid tap gesture is reported.

valid-tap.gifFigure 5. Valid Tap

Figure 6 shows an invalid tap gesture caused by a brief touch. In this capture the finger touches for only two samples. Because this does not meet the minimum timing parameter, no gesture is reported.

invalid-tap-touch-too-short.gifFigure 6. Invalid Tap: Touch Too Short

Figure 7 shows an invalid tap gesture caused by the finger touching too long. Because the maximum timing parameter is exceeded, no gesture is reported.

NOTE

This behavior is different if double tap is supported (see Section 3.2.2).
invalid-tap-touch-too-long.gifFigure 7. Invalid Tap: Touch Too Long