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/*
 * #%L
 * **********************************************************************
 * ORGANIZATION  :  Pi4J
 * PROJECT       :  Pi4J :: Java Examples
 * FILENAME      :  MCP3424GpioExample.java
 *
 * This file is part of the Pi4J project. More information about
 * this project can be found here:  http://www.pi4j.com/
 * **********************************************************************
 * %%
 * Copyright (C) 2012 - 2016 Pi4J
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Lesser Public License for more details.
 *
 * You should have received a copy of the GNU General Lesser Public
 * License along with this program.  If not, see
 * .
 * #L%
 */

import java.io.IOException;

import com.pi4j.gpio.extension.mcp.MCP3424GpioProvider;
import com.pi4j.gpio.extension.mcp.MCP3424Pin;
import com.pi4j.io.gpio.GpioController;
import com.pi4j.io.gpio.GpioFactory;
import com.pi4j.io.gpio.GpioPin;
import com.pi4j.io.gpio.GpioPinAnalogInput;
import com.pi4j.io.gpio.event.GpioPinAnalogValueChangeEvent;
import com.pi4j.io.gpio.event.GpioPinListenerAnalog;
import com.pi4j.io.i2c.I2CBus;
import com.pi4j.io.i2c.I2CFactory.UnsupportedBusNumberException;

/**
 * 
 * This example code demonstrates how to setup a custom GpioProvider
 * for GPIO pin state control and monitoring.
 * 
 *
 * 
 * This example implements the MCP3424 GPIO expansion board.
 * More information about the board can be found here: *
 * http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
 * 
 *
 * 
 * The MCP3424 is connected via I2C connection to the Raspberry Pi and provides
 * 16 GPIO pins that can be used for either digital input or digital output pins.
 * 
 *
 * @author Alexander Falkenstern
 */
public class MCP3424GpioExample {

    public static void main(String args[]) throws InterruptedException, UnsupportedBusNumberException, IOException {

        System.out.println("<--Pi4J--> MCP3424 GPIO Example ... started.");

        // create gpio controller
        final GpioController gpio = GpioFactory.getInstance();

        // create custom MCP3424 GPIO provider
        final MCP3424GpioProvider provider = new MCP3424GpioProvider(I2CBus.BUS_1, 0x6C, 18, 1);

        // provision gpio input pins from MCP3424
        GpioPinAnalogInput inputs[] = { gpio.provisionAnalogInputPin(provider, MCP3424Pin.GPIO_CH0, "Channel-0"),
                gpio.provisionAnalogInputPin(provider, MCP3424Pin.GPIO_CH1, "Channel-1"),
                gpio.provisionAnalogInputPin(provider, MCP3424Pin.GPIO_CH2, "Channel-2"),
                gpio.provisionAnalogInputPin(provider, MCP3424Pin.GPIO_CH3, "Channel-3") };

        // Define the amount that the ADC input conversion value must change before
        // a 'GpioPinAnalogValueChangeEvent' is raised.  This is used to prevent unnecessary
        // event dispatching for an analog input that may have an acceptable or expected
        // range of value drift.
        provider.setEventThreshold(0, inputs); // all inputs; alternatively you can set thresholds on each input discretely

        // Print current analog input conversion values from each input channel
        for(GpioPinAnalogInput input : inputs){
            System.out.print(" [" + input.getName() + "] : RAW VALUE = " + input.getValue());
            System.out.println(" -> " + provider.getAnalogValue(input.getPin()) + " V");
        }

        // create and register gpio pin listener
        gpio.addListener(new GpioPinListenerAnalog() {
            @Override
            public void handleGpioPinAnalogValueChangeEvent(GpioPinAnalogValueChangeEvent event) {
            	// get pin
            	GpioPin pin = event.getPin();

            	// get RAW value
                double value = event.getValue();

            	// get Volt value
                double analog = provider.getAnalogValue(pin.getPin());

                // display output
                System.out.print(" [" + pin + "] : RAW VALUE = " + value);
                System.out.println(" -> " + analog + " V");
            }
        }, inputs);

        provider.setMonitorInterval(50);
        provider.setMonitorEnabled(true);

        // Keep this sample program running for 10 minutes
        for (int count = 0; count < 600; count++) {
            Thread.sleep(1000);
        }

        // stop all GPIO activity/threads by shutting down the GPIO controller
        // (this method will forcefully shutdown all GPIO monitoring threads and scheduled tasks)
        gpio.shutdown();

        System.out.println("<--Pi4J--> Exiting MCP3424 GPIO Example.");
    }
}