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

2.3.2 Wheel Gesture

The processWheelGesture() function, located in file media_player_wheel.c, is called from the wheel sensor handler and operates as a state machine performing the gesture processing after every wheel sensor measurement. This function uses the timing and motion parameters from the SliderGestureParams data structure:

tSensorGestureParams WheelGestureParams = { .ui16TouchSampleCount_Min = 3, .ui16TouchSampleCount_Max = 16, .ui16SwipeSampleCount_Max = 10, .ui16FingerDistance_Min = 3, .ui16SwipeDistance_Min = 10, .ui16SlideStepSize_Min = 5, };

Figure 2 shows the state machine states and actions.

wheel-fsm.gifFigure 2. Wheel Sensor State Diagram