Fixes based on Fleker's review, with thanks!

sensehat/README.md

@@ -55,15 +55,17 @@ display.draw(bitmap);
 display.close();
 ```
 ```
-                try (BaroTemp bt = SenseHat.openBaroTemp()) {
-                    bt.setBarometerOffset(-6.2);
-                    Log.i(TAG, "PressureRaw: " + bt.getBarometerRaw());
-                    Log.i(TAG, "TemperatureRaw: " + bt.getTemperatureRaw());
-                    Log.i(TAG, "Pressure: " + bt.getBarometer());
-                    Log.i(TAG, "Temperature: " + bt.getTemperature());
-                } catch (Exception e) {
-                    Log.e(TAG, "Oops", e);
-                }
+    // just a snippet that verifies the device is working
+    // your actual use would of course be much more awesome
+    try (BaroTemp bt = SenseHat.openBaroTemp()) {
+        bt.setBarometerOffset(-6.2);
+        Log.i(TAG, "PressureRaw: " + bt.getBarometerRaw());
+        Log.i(TAG, "TemperatureRaw: " + bt.getTemperatureRaw());
+        Log.i(TAG, "Pressure: " + bt.getBarometer());
+        Log.i(TAG, "Temperature: " + bt.getTemperature());
+    } catch (Exception e) {
+        Log.e(TAG, "Oops", e);
+    }
 ```
 
 License

sensehat/src/main/java/com/google/android/things/contrib/driver/sensehat/BaroTemp.java

@@ -48,7 +48,7 @@ public class BaroTemp implements AutoCloseable {
     // The next two registers need special soldering
     private final int LPS_RPDS_L = 0x39;//  Pressure offset for differential pressure computing, low byte
     private final int LPS_RPDS_H = 0x3A; //  Differential offset, high byte
-    private int milliBarAdjust = 0;
+    private int mMillibarAdjust = 0;
 
     /**
      * Create a new barometric pressure and temperature sensor driver connected on the given I2C bus.
@@ -101,18 +101,25 @@ private int readSigned16(int a0, int a1) throws IOException {
     }
 
     /**
-     * The sensor seems to have an offset to the actual pressure. You can find your local "real" pressure quite easily on the web. Get the measured value from the
-     * sensor and compute the difference. The value obtained can be passed to this method to "calibrate" your board's sensor.
+     * The sensor seems to have an offset to the actual pressure. You can find your local "real"
+     * pressure quite easily on the web. Get the measured value from the sensor and compute the
+     * difference. The value obtained can be passed to this method to "calibrate" your board's
+     * sensor. In the author's case the difference was 6.2 hPa which is quite significant. This
+     * error was confirmed with another (unrelated) sensor.
      *
-     * @param hPa difference to actual air pressure
+     * @param hPa difference to actual air pressure in hectoPascal (hPa) or millibar.
      * @throws IOException from I2cDevice
      */
     public void setBarometerOffset(double hPa) throws IOException {
-        this.milliBarAdjust = (int) Math.round(hPa * 4096);
+        this.mMillibarAdjust = (int) Math.round(hPa * 4096);
     }
 
     /**
-     * Fetch raw value, see the data sheet. Note that this call waits for data to be available.
+     * Fetch raw value, see the data sheet. <p>Note that this call waits for data to be available.
+     * From the data sheet the (selected) refresh rate is 12.5 Hz so the max wait could be
+     * 1000/12.5 = 80 milliseconds with an average of 40 milliseconds. Call from asynchronous code
+     * if this is an issue. If your code calls this method less frequently then 12.5 times per
+     * second there will be no wait.</p>
      *
      * @return The raw sensor value, adjusted by the given offset (if any).
      * @throws IOException from I2cDevice
@@ -126,11 +133,15 @@ public int getBarometerRaw() throws IOException {
                 throw new IOException(e);
             }
         }
-        return readSigned24(LPS_PRESS_OUT_XL, LPS_PRESS_OUT_L, LPS_PRESS_OUT_H) + milliBarAdjust;
+        return readSigned24(LPS_PRESS_OUT_XL, LPS_PRESS_OUT_L, LPS_PRESS_OUT_H) + mMillibarAdjust;
     }
 
     /**
-     * Fetch raw value, see the data sheet. Note that this call waits for data to be available.
+     * Fetch raw value, see the data sheet. <p>Note that this call waits for data to be available.
+     * From the data sheet the (selected) refresh rate is 12.5 Hz so the max wait could be
+     * 1000/12.5 = 80 milliseconds with an average of 40 milliseconds. Call from asynchronous code
+     * if this is an issue. If your code calls this method less frequently then 12.5 times per
+     * second there will be no wait.</p>
      *
      * @return The raw sensor value.
      * @throws IOException from I2cDevice
@@ -148,20 +159,29 @@ public int getTemperatureRaw() throws IOException {
     }
 
     /**
-     * Fetch air pressure in hPa (milli bar). Note that this call waits for data to be available.
+     * Fetch air pressure in hPa (millibar). <p>Note that this call waits for data to be available.
+     * From the data sheet the (selected) refresh rate is 12.5 Hz so the max wait could be
+     * 1000/12.5 = 80 milliseconds with an average of 40 milliseconds. Call from asynchronous code
+     * if this is an issue. If your code calls this method less frequently then 12.5 times per
+     * second there will be no wait.</p>
      *
-     * @return The current air pressure, adjusted by the given offset (if any).
+     * @return The current air pressure in hPa(millibar), adjusted by the given offset (if any).
      * @throws IOException from I2cDevice
      */
     public double getBarometer() throws IOException {
         return getBarometerRaw() / 4096.0;
     }
 
     /**
-     * Fetch the temperature in degrees Celcius. Note that the design of the SenseHat makes this more the
-     * temperature of the board then the actual (room) temperature!
+     * Fetch the temperature in degrees Celcius. Note that the design of the SenseHat makes this
+     * more the temperature of the board then the actual (room) temperature!
+     * <p>Also note that this call waits for data to be available.
+     * From the data sheet the (selected) refresh rate is 12.5 Hz so the max wait could be
+     * 1000/12.5 = 80 milliseconds with an average of 40 milliseconds. Call from asynchronous code
+     * if this is an issue. If your code calls this method less frequently then 12.5 times per
+     * second there will be no wait.</p>
      *
-     * @return The temperature as reported by the sensor.
+     * @return The temperature as reported by the sensor in degrees Celcius.
      * @throws IOException from I2cDevice
      */
     public double getTemperature() throws IOException {

sensehat/src/main/java/com/google/android/things/contrib/driver/sensehat/SenseHat.java

@@ -24,16 +24,46 @@
 @SuppressWarnings({"unused", "WeakerAccess"})
 public class SenseHat {
     public static final int I2C_DISPLAY_ADDRESS =  0x46;
-    public static final int I2C_LPS25H_ADDRESS =  0x46;
+    public static final int I2C_LPS25H_ADDRESS =  0x5C;
     public static final String BUS_NAME = "I2C1";
     public static final int DISPLAY_WIDTH = LedMatrix.WIDTH;
     public static final int DISPLAY_HEIGHT = LedMatrix.HEIGHT;
 
+    /**
+     * Connect to the LedMatrix of the SenseHat on a Raspberry Pi 3.
+     * @return The autoclosing LedMatrix object.
+     * @throws IOException If caused by the hardware.
+     */
     public static LedMatrix openDisplay() throws IOException {
         return new LedMatrix(BUS_NAME);
     }
 
+    /**
+     * Connect to the LPS25H barometer/temperature of the SenseHat sensor on a Raspberry Pi 3.
+     * @return The autoclosing BaroTemp object.
+     * @throws IOException If caused by the hardware.
+     */
     public static BaroTemp openBaroTemp() throws IOException {
         return new BaroTemp(BUS_NAME);
     }
+
+    /**
+     * Connect to the LedMatrix of the SenseHat.
+     * @param busName The name of the I2C bus device on a non-raspi3 board.
+     * @return The autoclosing LedMatrix object.
+     * @throws IOException If caused by the hardware.
+     */
+    public static LedMatrix openDisplay(final String busName) throws IOException {
+        return new LedMatrix(busName);
+    }
+
+    /**
+     * Connect to the LPS25H barometer/temperature of the SenseHat sensor.
+     * @param busName The name of the I2C bus device on a non-raspi3 board.
+     * @return The autoclosing BaroTemp object.
+     * @throws IOException If caused by the hardware.
+     */
+    public static BaroTemp openBaroTemp(final String busName) throws IOException {
+        return new BaroTemp(busName);
+    }
 }