cap12xx

CAP12XX driver for Android Things

This driver supports capacitive touch controls build on the CAP12XX family of chips (CAP1203, CAP1293, CAP1206, CAP1296, CAP1208 and CAP1298).

NOTE: these drivers are not production-ready. They are offered as sample implementations of Android Things user space drivers for common peripherals as part of the Developer Preview release. There is no guarantee of correctness, completeness or robustness.

How to use the driver

Gradle dependency

To use the cap12xx driver, simply add the line below to your project's build.gradle, where <version> matches the last version of the driver available on jcenter.

dependencies {
    compile 'com.google.android.things.contrib:driver-cap12xx:<version>'
}

Sample usage

import com.google.android.things.contrib.driver.cap12xx.Cap12xx;

// Access the capacitive touch control:

Cap12xx mCapTouchControl;

try {
    mCapTouchControl = new Cap12xx(
            i2cBusName,                     // required I2C
            gpioPinName,                    // optional GPIO for interrupt alerts
            Cap12xx.Configuration.CAP1208   // choose whichever matches your chip
    );
    mCapTouchControl.setOnCapTouchListener(new Cap12xx.OnCapTouchListener() {
        @Override
        public void onCapTouchEvent(Cap12xx controller, boolean[] inputStatus) {
            // do something awesome
        }
    });
} catch (IOException e) {
    // couldn't configure the touch control...
}

// Close the capacitive touch control when finished:

try {
    mCapTouchControl.close();
} catch (IOException e) {
    // error closing servo
}

Instead of listening to touches directly, you can register the capacitive touch control with the system and receive KeyEvents using the standard Android APIs:

int[] keyCodes = new int[] {
        KevEvent.KEYCODE_1, KevEvent.KEYCODE_2, ... KevEvent.KEYCODE_8
};
Cap12xxInputDriver mInputDriver;

try {
    mInputDriver = new Cap12xxInputDriver(
            this,                           // context
            i2cBusName,
            null,
            Cap12xx.Configuration.CAP1208,  // 8 input channels
            keyCodes                        // keycodes mapped to input channels
    );

    // Disable repeated events
    mInputDriver.setRepeatRate(Cap12xx.REPEAT_DISABLE);
    // Block touches above 4 unique inputs
    mInputDriver.setMultitouchInputMax(4);

    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
}

License

Copyright 2016 Google Inc.

Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.