BatteryService.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #ifndef __BLE_BATTERY_SERVICE_H__
00018 #define __BLE_BATTERY_SERVICE_H__
00019 
00020 #include "BLEDevice.h"
00021 
00022 /**
00023 * @class BatteryService
00024 * @brief BLE Battery Service. This service displays the battery level from 0%->100% represented as a 8bit number.<br>
00025 * Service:  https://developer.bluetooth.org/gatt/services/Pages/ServiceViewer.aspx?u=org.bluetooth.service.battery_service.xml <br>
00026 * Battery Level Char:  https://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.battery_level.xml
00027 */
00028 class BatteryService {
00029 public:
00030     /**
00031     * @param[ref] _ble
00032     *               BLEDevice object for the underlying controller.
00033     * @param[in] level
00034     *               8bit batterly level. Usually used to represent percentage of batterly charge remaining.
00035     */
00036     BatteryService (BLEDevice &_ble, uint8_t level = 100) :
00037         ble(_ble),
00038         batteryLevel(level),
00039         batteryLevelCharacteristic(GattCharacteristic::UUID_BATTERY_LEVEL_CHAR, &batteryLevel, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY) {
00040 
00041         static bool serviceAdded = false; /* We should only ever need to add the heart rate service once. */
00042         if (serviceAdded) {
00043             return;
00044         }
00045 
00046         GattCharacteristic *charTable[] = {&batteryLevelCharacteristic};
00047         GattService         batteryService(GattService::UUID_BATTERY_SERVICE, charTable, sizeof(charTable) / sizeof(GattCharacteristic *));
00048 
00049         ble.addService(batteryService);
00050         serviceAdded = true;
00051     }
00052 
00053     /**
00054      * @brief Update the battery level with a new value. Valid values range from
00055      * 0..100. Anything outside this range will be ignored.
00056      *
00057      * @param newLevel
00058      *              update to battery level.
00059      */
00060     void updateBatteryLevel(uint8_t newLevel) {
00061         batteryLevel = newLevel;
00062         ble.updateCharacteristicValue (batteryLevelCharacteristic.getValueAttribute().getHandle(), &batteryLevel, 1);
00063     }
00064 
00065 private:
00066     BLEDevice &ble;
00067 
00068     uint8_t    batteryLevel;
00069     ReadOnlyGattCharacteristic<uint8_t> batteryLevelCharacteristic;
00070 };
00071 
00072 #endif /* #ifndef __BLE_BATTERY_SERVICE_H__*/