https://github.com/Nilhcem/mpr121-androidthings

MPR121 driver for Android Things
https://github.com/Nilhcem/mpr121-androidthings

Last synced: about 2 months ago
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MPR121 driver for Android Things

• Host: GitHub
• URL: https://github.com/Nilhcem/mpr121-androidthings
• Owner: Nilhcem
• License: apache-2.0
• Created: 2017-02-19T08:23:55.000Z (almost 8 years ago)
• Default Branch: master
• Last Pushed: 2018-05-10T15:56:56.000Z (over 6 years ago)
• Last Synced: 2024-08-01T17:24:36.117Z (5 months ago)
• Language: Java
• Size: 279 KB
• Stars: 11
• Watchers: 1
• Forks: 4
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE

Awesome Lists containing this project

• awesome-android-things - MPR121 - Proximity capacitive touch sensor (Useful links / Drivers)
• awesome-android-things - MPR121 - Proximity capacitive touch sensor (Useful links / Drivers)

README

        
# MPR121 capacitive touch sensor driver for Android Things

A port of the [Adafruit MPR121][adafruit-mpr121] Arduino library for Android Things.

## Download

```groovy

dependencies {

    compile 'com.nilhcem.androidthings:driver-mpr121:0.0.3'

}

```

## Usage

### Registering with the system

```java

int[] keyCodes = new int[] { KevEvent.KEYCODE_1, KevEvent.KEYCODE_2, ... KevEvent.KEYCODE_12 };

Mpr121InputDriver inputDriver;

HandlerThread handlerThread = new HandlerThread("Mpr121Thread");

handlerThread.start();

handler = new Handler(handlerThread.getLooper());

try {

    inputDriver = new Mpr121InputDriver(i2cBusName, handler, keyCodes);

    mInputDriver.register();

} catch (IOException e) {

    // couldn't configure the input driver...

}

// Override key event callbacks in your Activity:

@Override

public boolean onKeyDown(int keyCode, KeyEvent event) {

    switch (keyCode) {

        case KeyEvent.KEYCODE_1:

            doSomethingAwesome();

            return true; // handle keypress

        // other cases...

    }

    return super.onKeyDown(keyCode, event);

}

// Unregister and close the input driver when finished:

mInputDriver.unregister;

try {

    mInputDriver.close();

} catch (IOException e) {

    // error closing input driver

}

```

Also, don't forget to add the required permission to your app's manifest file:

```xml

```

### Calling the driver manually

You can call the `Mpr121` class directly if you prefer not to receive events from the system:

```java

// Instantiate the driver

Mpr121 peripheralDevice = new Mpr121(i2cName);

// Get the current state of each electrode

int data = peripheralDevice.getTouched();

// Loop to check the state of these electrodes

// Ideally, place this code in a thread to check continuously and add a listener when a state changes

boolean[] inputStatus = new boolean[Mpr121.NB_ELECTRODES];

for (int i = 0; i < Mpr121.NB_ELECTRODES; i++) {

    if ((data & (1 << i)) != 0) {

        if (!inputStatus[i]) {

            Log.d(TAG, "#" + i + " touched");

            inputStatus[i] = true;

        }

    } else {

        if (inputStatus[i]) {

            Log.d(TAG, "#" + i + " released");

            inputStatus[i] = false;

        }

    }

}

// Finally, close the driver

peripheralDevice.close();

```

## Sample project

The sample project uses a passive buzzer to play a sound when an electrode is touched.

### Schematic:

![schematic][]

If you prefer playing a real sound file instead (e.g.: wav/mp3), use the `SoundPoolHelper` instead of the `PassiveBuzzerHelper` in the `MainActivity`, and place your assets in `res/raw` (from: `res/raw/sound0.mp3` to: `res/raw/sound11.mp3`)

[adafruit-mpr121]: https://github.com/adafruit/Adafruit_MPR121/

[schematic]: https://raw.githubusercontent.com/Nilhcem/mpr121-androidthings/master/assets/schematic.png