java: Update HelloTinyB sample to read temp from TI Sensor Tagv0.3.2

Signed-off-by: Petre Eftime <[email protected]>

1 files changed, 118 insertions, 59 deletions

diff --git a/examples/java/HelloTinyB.java b/examples/java/HelloTinyB.java
index 84656581..2a2fbb26 100644
--- a/examples/java/HelloTinyB.java
+++ b/examples/java/HelloTinyB.java
@@ -3,54 +3,54 @@ import java.util.*;
 
 public class HelloTinyB {
     private static final float SCALE_LSB = 0.03125f;
+    static boolean running = true;
 
     static void printDevice(BluetoothDevice device) {
         System.out.print("Address = " + device.getAddress());
-        System.out.print("Name = " + device.getName());
-        System.out.print("Connected = " + device.getConnected());
-        System.out.println("");
+        System.out.print(" Name = " + device.getName());
+        System.out.print(" Connected = " + device.getConnected());
+        System.out.println();
+    }
+
+    static float convertCelsius(int raw) {
+        return raw / 128f;
     }
 
     /*
-     * After discovery is started, new devices will be detected. We can
-     * get a list of all devices through the manager's getDevices
-     * method.
-     * We can the look through the list of devices to find the device
-     * with the MAC which we provided as a parameter.
-     * We continue looking until we find it, or we try 15 times (1 minutes).
+     * After discovery is started, new devices will be detected. We can get a list of all devices through the manager's
+     * getDevices method. We can the look through the list of devices to find the device with the MAC which we provided
+     * as a parameter. We continue looking until we find it, or we try 15 times (1 minutes).
      */
     static BluetoothDevice getDevice(String address) throws InterruptedException {
         BluetoothManager manager = BluetoothManager.getBluetoothManager();
         BluetoothDevice sensor = null;
-        for (int i = 0; i < 15; ++i) {
-                List<BluetoothDevice> list = manager.getDevices();
-
-                for (BluetoothDevice device : list) {
-                    printDevice(device);
-                    /*
-                     * Here we check if the address matches.
-                     */
-                    if (device.getAddress().equals(address))
-                        sensor = device;
-                }
+        for (int i = 0; (i < 15) && running; ++i) {
+            List<BluetoothDevice> list = manager.getDevices();
+
+            for (BluetoothDevice device : list) {
+                printDevice(device);
+                /*
+                 * Here we check if the address matches.
+                 */
+                if (device.getAddress().equals(address))
+                    sensor = device;
+            }
 
-                if (sensor != null) {
-                    return sensor;
-                }
-                Thread.sleep(4000);
+            if (sensor != null) {
+                return sensor;
             }
-            return null;
+            Thread.sleep(4000);
+        }
+        return null;
     }
 
     /*
-     * Our device should expose a temperature service, which has a UUID
-     * we can find out from the data sheet.
-     * The service description of the SensorTag can be found here:
-     * http://processors.wiki.ti.com/images/a/a8/BLE_SensorTag_GATT_Server.pdf
-     * The service we are looking for has the short UUID AA00 which we insert into
-     * the TI Base UUID: f000XXXX-0451-4000-b000-000000000000
+     * Our device should expose a temperature service, which has a UUID we can find out from the data sheet. The service
+     * description of the SensorTag can be found here:
+     * http://processors.wiki.ti.com/images/a/a8/BLE_SensorTag_GATT_Server.pdf. The service we are looking for has the
+     * short UUID AA00 which we insert into the TI Base UUID: f000XXXX-0451-4000-b000-000000000000
      */
-    static BluetoothGattService getService (BluetoothDevice device, String UUID) throws InterruptedException {
+    static BluetoothGattService getService(BluetoothDevice device, String UUID) throws InterruptedException {
         System.out.println("Services exposed by device:");
         BluetoothGattService tempService = null;
         List<BluetoothGattService> bluetoothServices = null;
@@ -59,26 +59,32 @@ public class HelloTinyB {
 
             for (BluetoothGattService service : bluetoothServices) {
                 System.out.println("UUID: " + service.getUuid());
-		if (service.getUuid().equals(UUID))
-			tempService = service;
+                if (service.getUuid().equals(UUID))
+                    tempService = service;
             }
             Thread.sleep(4000);
-        } while (bluetoothServices != null && bluetoothServices.isEmpty());
+        } while (bluetoothServices != null && bluetoothServices.isEmpty() && running);
         return tempService;
     }
 
+    static BluetoothGattCharacteristic getCharacteristic(BluetoothGattService service, String UUID) {
+        List<BluetoothGattCharacteristic> characteristics = service.getCharacteristics();
+
+        for (BluetoothGattCharacteristic characteristic : characteristics) {
+            if (characteristic.getUuid().equals(UUID))
+                return characteristic;
+        }
+        return null;
+    }
+
     /*
-     * This program connects to a TI SensorTag 2.0 and reads the temperature
-     * characteristic exposed by the device over Bluetooth Low Energy.
-     * The parameter provided to the program should be the MAC address of
-     * the device.
+     * This program connects to a TI SensorTag 2.0 and reads the temperature characteristic exposed by the device over
+     * Bluetooth Low Energy. The parameter provided to the program should be the MAC address of the device.
      *
-     * A wiki describing the sensor is found here:
-     * http://processors.wiki.ti.com/index.php/CC2650_SensorTag_User's_Guide
+     * A wiki describing the sensor is found here: http://processors.wiki.ti.com/index.php/CC2650_SensorTag_User's_Guide
      *
-     * The API used in this example is based on TinyB v0.3, which only supports
-     * polling, but v0.4 will introduce a simplied API for discovering devices
-     * and services.
+     * The API used in this example is based on TinyB v0.3, which only supports polling, but v0.4 will introduce a
+     * simplied API for discovering devices and services.
      */
     public static void main(String[] args) throws InterruptedException {
 
@@ -87,19 +93,28 @@ public class HelloTinyB {
             System.exit(-1);
         }
 
+        final Thread mainThread = Thread.currentThread();
+        Runtime.getRuntime().addShutdownHook(new Thread() {
+            public void run() {
+                running = false;
+                try {
+                    mainThread.join();
+                } catch (InterruptedException e) {
+                    e.printStackTrace();
+                }
+            }
+        });
+
         /*
-         * To start looking of the device, we first must initialize the TinyB
-         * library. The way of interacting with the library is through
-         * the BluetoothManager. There can be only one BluetoothManager at one
-         * time, and the reference to it is obtained through the
-         * getBluetoothManager method.
+         * To start looking of the device, we first must initialize the TinyB library. The way of interacting with the
+         * library is through the BluetoothManager. There can be only one BluetoothManager at one time, and the
+         * reference to it is obtained through the getBluetoothManager method.
          */
         BluetoothManager manager = BluetoothManager.getBluetoothManager();
 
         /*
-         * The manager will try to initialize a BluetoothAdapter if any adapter
-         * is present in the system. To initialize discovery we can call
-         * startDiscovery, which will put the default adapter in discovery mode.
+         * The manager will try to initialize a BluetoothAdapter if any adapter is present in the system. To initialize
+         * discovery we can call startDiscovery, which will put the default adapter in discovery mode.
          */
         boolean discoveryStarted = manager.startDiscovery();
 
@@ -126,19 +141,63 @@ public class HelloTinyB {
             System.exit(-1);
         }
 
-        BluetoothGattService tempService =
-            getService(sensor, "f000aa00-0451-4000-b000-000000000000");
+        BluetoothGattService tempService = getService(sensor, "f000aa00-0451-4000-b000-000000000000");
 
         if (tempService == null) {
-            /*
-             * This device does not have the temperature service we are looking for.
-             */
+            System.err.println("This device does not have the temperature service we are looking for.");
             sensor.disconnect();
             System.exit(-1);
         }
+        System.out.println("Found service " + tempService.getUuid());
 
-        List<BluetoothGattCharacteristic> temperatureCharacteristics =
-            tempService.getCharacteristics();
+        BluetoothGattCharacteristic tempValue = getCharacteristic(tempService, "f000aa01-0451-4000-b000-000000000000");
+        BluetoothGattCharacteristic tempConfig = getCharacteristic(tempService, "f000aa02-0451-4000-b000-000000000000");
+        BluetoothGattCharacteristic tempPeriod = getCharacteristic(tempService, "f000aa03-0451-4000-b000-000000000000");
+
+        if (tempValue == null || tempConfig == null || tempPeriod == null) {
+            System.err.println("Could not find the correct characteristics.");
+            sensor.disconnect();
+            System.exit(-1);
+        }
+
+        System.out.println("Found the temperature characteristics");
+
+        /*
+         * Turn on the Temperature Service by writing 1 in the configuration characteristic, as mentioned in the PDF
+         * mentioned above. We could also modify the update interval, by writing in the period characteristic, but the
+         * default 1s is good enough for our purposes.
+         */
+        byte[] config = { 0x01 };
+        tempConfig.writeValue(config);
+
+        /*
+         * Each second read the value characteristic and display it in a human readable format.
+         */
+        while (running) {
+            byte[] tempRaw = tempValue.readValue();
+            System.out.print("Temp raw = {");
+            for (byte b : tempRaw) {
+                System.out.print(String.format("%02x,", b));
+            }
+            System.out.print("}");
+
+            /*
+             * The temperature service returns the data in an encoded format which can be found in the wiki. Convert the
+             * raw temperature format to celsius and print it. Conversion for object temperature depends on ambient
+             * according to wiki, but assume result is good enough for our purposes without conversion.
+             */
+            int objectTempRaw = tempRaw[0] + (tempRaw[1] << 8);
+            int ambientTempRaw = tempRaw[2] + (tempRaw[3] << 8);
+
+            float objectTempCelsius = convertCelsius(objectTempRaw);
+            float ambientTempCelsius = convertCelsius(ambientTempRaw);
+
+            System.out.println(
+                    String.format(" Temp: Object = %fC, Ambient = %fC", objectTempCelsius, ambientTempCelsius));
+
+            Thread.sleep(1000);
+        }
+        sensor.disconnect();
 
     }
 }