/*
* #%L
* **********************************************************************
* ORGANIZATION : Pi4J
* PROJECT : Pi4J :: Java Examples
* FILENAME : MCP23S17GpioExample.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 - 2013 Pi4J
* %%
* Licensed 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.
* #L%
*/
import java.io.IOException;
import com.pi4j.gpio.extension.mcp.MCP23S17GpioProvider;
import com.pi4j.gpio.extension.mcp.MCP23S17Pin;
import com.pi4j.io.gpio.GpioController;
import com.pi4j.io.gpio.GpioFactory;
import com.pi4j.io.gpio.GpioPinDigitalInput;
import com.pi4j.io.gpio.GpioPinDigitalOutput;
import com.pi4j.io.gpio.PinPullResistance;
import com.pi4j.io.gpio.PinState;
import com.pi4j.io.gpio.event.GpioPinDigitalStateChangeEvent;
import com.pi4j.io.gpio.event.GpioPinListenerDigital;
import com.pi4j.wiringpi.Spi;
/**
* <p>
* This example code demonstrates how to setup a custom GpioProvider
* for GPIO pin state control and monitoring.
* </p>
*
* <p>
* This example implements the MCP23S17 GPIO expansion board.
* More information about the board can be found here: *
* http://ww1.microchip.com/downloads/en/DeviceDoc/21952b.pdf
* </p>
*
* <p>
* The MCP23S17 is connected via SPI connection to the Raspberry Pi and provides
* 16 GPIO pins that can be used for either digital input or digital output pins.
* </p>
*
* @author Robert Savage
*/
public class MCP23S17GpioExample {
public static void main(String args[]) throws InterruptedException, IOException {
System.out.println("<--Pi4J--> MCP23S17 GPIO Example ... started.");
// create gpio controller
final GpioController gpio = GpioFactory.getInstance();
// create custom MCP23017 GPIO provider
final MCP23S17GpioProvider gpioProvider = new MCP23S17GpioProvider(MCP23S17GpioProvider.DEFAULT_ADDRESS, Spi.CHANNEL_0);
// provision gpio input pins from MCP23S17
GpioPinDigitalInput myInputs[] = {
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B0, "MyInput-B0", PinPullResistance.PULL_UP),
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B1, "MyInput-B1", PinPullResistance.PULL_UP),
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B2, "MyInput-B2", PinPullResistance.PULL_UP),
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B3, "MyInput-B3", PinPullResistance.PULL_UP),
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B4, "MyInput-B4", PinPullResistance.PULL_UP),
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B5, "MyInput-B5", PinPullResistance.PULL_UP),
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B6, "MyInput-B6", PinPullResistance.PULL_UP),
gpio.provisionDigitalInputPin(gpioProvider, MCP23S17Pin.GPIO_B7, "MyInput-B7", PinPullResistance.PULL_UP),
};
// create and register gpio pin listener
gpio.addListener(new GpioPinListenerDigital() {
@Override
public void handleGpioPinDigitalStateChangeEvent(GpioPinDigitalStateChangeEvent event) {
// display pin state on console
System.out.println(" --> GPIO PIN STATE CHANGE: " + event.getPin() + " = "
+ event.getState());
}
}, myInputs);
// provision gpio output pins and make sure they are all LOW at startup
GpioPinDigitalOutput myOutputs[] = {
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A0, "MyOutput-A0", PinState.LOW),
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A1, "MyOutput-A1", PinState.LOW),
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A2, "MyOutput-A2", PinState.LOW),
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A3, "MyOutput-A3", PinState.LOW),
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A4, "MyOutput-A4", PinState.LOW),
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A5, "MyOutput-A5", PinState.LOW),
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A6, "MyOutput-A6", PinState.LOW),
gpio.provisionDigitalOutputPin(gpioProvider, MCP23S17Pin.GPIO_A7, "MyOutput-A7", PinState.LOW)
};
// keep program running for 20 seconds
for (int count = 0; count < 10; count++) {
gpio.setState(true, myOutputs);
Thread.sleep(1000);
gpio.setState(false, myOutputs);
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();
}
}