io.silverspoon.bulldog.devices.sensors.BH1750LightIntensitySensor Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of bulldog-devices Show documentation

There is a newer version: 0.3.0

package io.silverspoon.bulldog.devices.sensors;

import java.io.IOException;

import io.silverspoon.bulldog.core.io.bus.i2c.I2cBus;
import io.silverspoon.bulldog.core.io.bus.i2c.I2cConnection;
import io.silverspoon.bulldog.core.io.bus.i2c.I2cDevice;
import io.silverspoon.bulldog.core.util.BitMagic;
import io.silverspoon.bulldog.core.util.BulldogUtil;

public class BH1750LightIntensitySensor extends I2cDevice {

   public static final int MODE_HIGH_RES_1LX_CONTINUOUS = 0b00010000;
   public static final int MODE_HIGH_RES_1LX_ONE_TIME = 0b00100000;
   public static final int MODE_HIGH_RES_05_LX_CONTINUOUS = 0b00010001;
   public static final int MODE_HIGH_RES_05_LX_ONE_TIME = 0b00100001;
   public static final int MODE_LOW_RES_4LX_CONTINUOUS = 0b00010011;
   public static final int MODE_LOW_RES_4LX_ONE_TIME = 0b00100011;

   public static final int COMMAND_POWER_OFF = 0b00000000;
   public static final int COMMAND_POWER_ON = 0b00000001;
   public static final int COMMAND_RESET = 0b00000111;

   private int activeMode = 0;

   public BH1750LightIntensitySensor(I2cBus bus, int address) {
      super(bus, address);
   }

   public BH1750LightIntensitySensor(I2cConnection connection) {
      super(connection);
   }

   public void initMode(int mode) throws IOException {
      getBusConnection().writeByte(mode);
      activeMode = mode;
   }

   public double readLuminance() throws IOException {
      if (BitMagic.isBitSet(activeMode, 6)) {
         getBusConnection().writeByte(COMMAND_POWER_ON);
         getBusConnection().writeByte(activeMode);
      }

      byte[] buffer = new byte[2];
      getBusConnection().readBytes(buffer);
      int intValue = (((BulldogUtil.getUnsignedByte(buffer[0]) << 8)) | BulldogUtil.getUnsignedByte(buffer[1]));
      double value = intValue / 1.2;
      return value;
   }

   public double readLuminanceNormalized() throws IOException {
      double luminance = readLuminance();
      double normalized = Math.log10(luminance) / 5.0;
      if (normalized < 0 || Double.isInfinite(normalized)) {
         return 0.0;
      }

      return normalized;
   }
}