Example lcd code

pi4j-spring-boot-starter-sample-app/src/main/java/com/pi4j/spring/boot/sample/app/controller/Pi4JController.java

@@ -1,8 +1,7 @@
 package com.pi4j.spring.boot.sample.app.controller;
 
-import com.pi4j.context.Context;
-import com.pi4j.io.gpio.digital.DigitalOutput;
 import com.pi4j.io.gpio.digital.DigitalState;
+import com.pi4j.spring.boot.sample.app.service.Pi4JService;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -16,22 +15,24 @@
 public class Pi4JController {
 
     private static final Logger logger = LoggerFactory.getLogger(Pi4JController.class);
-    private static final int PIN_LED = 22; // PIN 15 = BCM 22
-    private final DigitalOutput led;
+    private final Pi4JService pi4JService;
 
-    public Pi4JController(@Autowired Context pi4j) {
-        // LED example is based on https://www.pi4j.com/getting-started/minimal-example-application/
-        led = pi4j.digitalOutput().create(PIN_LED);
-        logger.info("LED initialized on pin {}", PIN_LED);
+    public Pi4JController(@Autowired Pi4JService pi4JService) {
+        this.pi4JService = pi4JService;
     }
 
-    @GetMapping("/led/{status}")
-    public String setLedStatus(@PathVariable Boolean status) {
-        try {
-            led.state(status ? DigitalState.HIGH : DigitalState.LOW);
-            return "LED status set to " + (status ? "ON" : "OFF");
-        } catch (Exception e) {
-            return "Error while changing the LED status: " + e.getMessage();
-        }
+    @GetMapping("/led/{state}")
+    public Boolean setLedStatus(@PathVariable Boolean state) {
+        return pi4JService.setLedState(state);
+    }
+
+    @GetMapping("/button")
+    public DigitalState setLedStatus() {
+        return pi4JService.getButtonState();
+    }
+
+    @GetMapping("/lcd/{line}/{text}")
+    public Boolean setLcdText(@PathVariable Integer line, @PathVariable String text) {
+        return pi4JService.setLcdText(line, text);
     }
 }

pi4j-spring-boot-starter-sample-app/src/main/java/com/pi4j/spring/boot/sample/app/lcd/Component.java

@@ -0,0 +1,74 @@
+package com.pi4j.spring.boot.sample.app.lcd;
+
+import java.time.Duration;
+import java.util.logging.ConsoleHandler;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+public abstract class Component {
+    /**
+     * Logger instance
+     */
+    private static final Logger logger = Logger.getLogger("Pi4J Components");
+
+    static {
+        Level appropriateLevel = Level.INFO;
+        //Level appropriateLevel = Level.FINE; //use if 'debug'
+
+        System.setProperty("java.util.logging.SimpleFormatter.format",
+                "%4$s: %5$s [%1$tl:%1$tM:%1$tS %1$Tp]%n");
+
+        logger.setLevel(appropriateLevel);
+        logger.setUseParentHandlers(false);
+        ConsoleHandler handler = new ConsoleHandler();
+        handler.setLevel(appropriateLevel);
+        logger.addHandler(handler);
+    }
+
+    protected Component() {
+    }
+
+    /**
+     * Override this method to clean up all used resources
+     */
+    public void reset() {
+        //nothing to do by default
+    }
+
+    protected void logInfo(String msg, Object... args) {
+        logger.info(() -> String.format(msg, args));
+    }
+
+    protected void logError(String msg, Object... args) {
+        logger.severe(() -> String.format(msg, args));
+    }
+
+    protected void logDebug(String msg, Object... args) {
+        logger.fine(() -> String.format(msg, args));
+    }
+
+    protected void logException(String msg, Throwable exception) {
+        logger.log(Level.SEVERE, msg, exception);
+    }
+
+    /**
+     * Utility function to sleep for the specified amount of milliseconds.
+     * An {@link InterruptedException} will be caught and ignored while setting the interrupt flag again.
+     *
+     * @param duration Time to sleep
+     */
+    protected void delay(Duration duration) {
+        try {
+            long nanos = duration.toNanos();
+            long millis = nanos / 1_000_000;
+            int remainingNanos = (int) (nanos % 1_000_000);
+            Thread.sleep(millis, remainingNanos);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+        }
+    }
+
+    protected <T> T asMock(Class<T> type, Object instance) {
+        return type.cast(instance);
+    }
+}

pi4j-spring-boot-starter-sample-app/src/main/java/com/pi4j/spring/boot/sample/app/lcd/I2CDevice.java

@@ -0,0 +1,83 @@
+package com.pi4j.spring.boot.sample.app.lcd;
+
+import com.pi4j.context.Context;
+import com.pi4j.io.i2c.I2C;
+import com.pi4j.plugin.mock.provider.i2c.MockI2C;
+
+import java.time.Duration;
+
+public abstract class I2CDevice extends Component {
+
+    /**
+     * The Default BUS and Device Address.
+     * On the PI, you can look it up with the Command 'sudo i2cdetect -y 1'
+     */
+    protected static final int DEFAULT_BUS = 0x01;
+
+    /**
+     * The PI4J I2C component
+     */
+    private final I2C i2c;
+
+
+    protected I2CDevice(Context pi4j, int device, String name) {
+        i2c = pi4j.create(I2C.newConfigBuilder(pi4j)
+                .id("I2C-" + DEFAULT_BUS + "@" + device)
+                .name(name + "@" + device)
+                .bus(DEFAULT_BUS)
+                .device(device)
+                .build());
+        init(i2c);
+        logDebug("I2C device %s initialized", name);
+    }
+
+
+    /**
+     * send a single command to device
+     */
+    protected void sendCommand(byte cmd) {
+        i2c.write(cmd);
+        delay(Duration.ofNanos(100_000));
+    }
+
+    protected int readRegister(int register) {
+        return i2c.readRegisterWord(register);
+    }
+
+    /**
+     * send custom configuration to device
+     *
+     * @param config custom configuration
+     */
+    protected void writeRegister(int register, int config) {
+        i2c.writeRegisterWord(register, config);
+    }
+
+    /**
+     * send some data to device
+     *
+     * @param data
+     */
+    protected void write(byte data) {
+        i2c.write(data);
+    }
+
+    /**
+     * Execute Display commands
+     *
+     * @param command Select the LCD Command
+     * @param data    Setup command data
+     */
+    protected void sendCommand(byte command, byte data) {
+        sendCommand((byte) (command | data));
+    }
+
+    protected abstract void init(I2C i2c);
+
+    // --------------- for testing --------------------
+
+    public MockI2C mock() {
+        return asMock(MockI2C.class, i2c);
+    }
+
+}