com.diozero.devices.Keypad Maven / Gradle / Ivy
package com.diozero.devices;
/*-
* #%L
* Organisation: diozero
* Project: diozero - Core
* Filename: Keypad.java
*
* This file is part of the diozero project. More information about this project
* can be found at https://www.diozero.com/.
* %%
* Copyright (C) 2016 - 2021 diozero
* %%
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
* #L%
*/
import java.util.ArrayList;
import java.util.List;
import com.diozero.api.DeviceInterface;
import com.diozero.api.DigitalInputDevice;
import com.diozero.api.DigitalOutputDevice;
import com.diozero.api.GpioEventTrigger;
import com.diozero.api.GpioPullUpDown;
/**
* References:
*
* Note, this class should be run with the mmap provider as it configures input pull-up registers,
* something that cannot be done with the sysfs provider unfortunately. You can of course wire it up
* with your own pull-up resistors.
*/
public class Keypad implements DeviceInterface {
public static final char NO_KEY = '\0';
private DigitalInputDevice[] rows;
private DigitalOutputDevice[] cols;
private char[][] keys;
// Last read on / off state for all keys
private boolean[][] values;
public Keypad(int[] rowGpios, int[] colGpios, char[][] keys) {
// Validate keys array dimensions matches rowGpios and colGpios
if (keys.length != rowGpios.length || keys[0].length != colGpios.length) {
throw new IllegalArgumentException("Array dimensions do not match");
}
this.keys = keys;
rows = new DigitalInputDevice[rowGpios.length];
cols = new DigitalOutputDevice[colGpios.length];
int i=0;
for (int gpio : rowGpios) {
rows[i++] = new DigitalInputDevice(gpio, GpioPullUpDown.PULL_UP, GpioEventTrigger.NONE);
}
i=0;
for (int gpio : colGpios) {
cols[i++] = new DigitalOutputDevice(gpio, false, false);
}
values = new boolean[rows.length][cols.length];
}
public List getKeys() {
scanKeys();
List keys_pressed = new ArrayList<>();
for (int r=0; r