rainbowhat

Rainbow Hat driver for Android Things

This driver provides easy access to the peripherals available on the Rainbow Hat for Android Things:

• BMP280 temperature and pressure sensor (I2C)
• HT16K33 segment display (I2C)
• Capacitive buttons (GPIO)
• LEDs (GPIO)
• APA102 RGB LEDs (SPI)
• Piezo Buzzer (PWM)
• Servo header (PWM)

The pin/bus mapping and helper methods provided by this driver are only compatible with the following boards: Raspberry Pi 3 and NXP Pico i.MX7D.

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 rainbowhat 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-rainbowhat:<version>'
}

Sample usage

// import the RainbowHat driver
import com.google.android.things.contrib.driver.rainbowhat.RainbowHat;

// Light up the Red LED.
Gpio led = RainbowHat.openLedRed();
led.setValue(true);
// Close the device when done.
led.close();

// Display a string on the segment display.
AlphanumericDisplay segment = RainbowHat.openDisplay();
segment.setBrightness(Ht16k33.HT16K33_BRIGHTNESS_MAX);
segment.display("ABCD");
segment.setEnabled(true);
// Close the device when done.
segment.close();

// Play a note on the buzzer.
Speaker buzzer = RainbowHat.openPiezo();
buzzer.play(440);
// Stop the buzzer.
buzzer.stop();
// Close the device when done.
buzzer.close();

// Log the current temperature
Bmx280 sensor = RainbowHat.openSensor();
sensor.setTemperatureOversampling(Bmx280.OVERSAMPLING_1X);
Log.d(TAG, "temperature:" + sensor.readTemperature());
// Close the device when done.
sensor.close();

// Display the temperature on the segment display.
Bmx280 sensor = RainbowHat.openSensor();
sensor.setTemperatureOversampling(Bmx280.OVERSAMPLING_1X);
AlphanumericDisplay segment = RainbowHat.openDisplay();
segment.setBrightness(Ht16k33.HT16K33_BRIGHTNESS_MAX);
segment.display(sensor.readTemperature());
segment.setEnabled(true);
// Close the devices when done.
sensor.close();
segment.close();

// Light up the rainbow
Apa102 ledstrip = RainbowHat.openLedStrip();
ledstrip.setBrightness(31);
int[] rainbow = new int[RainbowHat.LEDSTRIP_LENGTH];
for (int i = 0; i < rainbow.length; i++) {
    rainbow[i] = Color.HSVToColor(255, new float[]{i * 360.f / rainbow.length, 1.0f, 1.0f});
}
ledstrip.write(rainbow);
// Close the device when done.
ledstrip.close();

// Detect when button 'A' is pressed.
Button button = RainbowHat.openButtonA();
button.setOnButtonEventListener(new Button.OnButtonEventListener() {
    @Override
    public void onButtonEvent(Button button, boolean pressed) {
        Log.d(TAG, "button A pressed:" + pressed);
    }
});
// Close the device when done.
button.close();

// Get native Android 'A' key events when button 'A' is pressed.
ButtonInputDriver inputDriver = RainbowHat.createButtonAInputDriver(
        KeyEvent.KEYCODE_A      // keyCode to send
);
inputDriver.register();

// In your Activity.
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_A) {
        // ...
    }
    return super.onKeyDown(keyCode, event);
}
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_A) {
        // ...
    }
    return super.onKeyUp(keyCode, event);
}

// Continuously report temperature.

// Register the sensor somewhere in your Activity initialization code
Bmx280SensorDriver  temperatureSensorDriver = new Bmx280SensorDriver("I2C1");
temperatureSensorDriver.registerTemperatureSensor();

// Now you can register the sensor callback for continously report temperature
final SensorManager sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
sensorManager.registerDynamicSensorCallback(new SensorManager.DynamicSensorCallback() {
    @Override
    public void onDynamicSensorConnected(Sensor sensor) {
        if (sensor.getType() == Sensor.TYPE_AMBIENT_TEMPERATURE) {
            sensorManager.registerListener(
                    new SensorEventListener() {
                        @Override
                        public void onSensorChanged(SensorEvent event) {
                            Log.i(TAG, "sensor changed: " + event.values[0]);
                        }
                        @Override
                        public void onAccuracyChanged(Sensor sensor, int accuracy) {
                            Log.i(TAG, "accuracy changed: " + accuracy);
                        }
                    },
                    sensor, SensorManager.SENSOR_DELAY_NORMAL);
        }
    }
});

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.