Mbed OS Reference | EnvironmentalService.h Source File

 /* mbed Microcontroller Library
  * Copyright (c) 2006-2020 ARM Limited
  *
  * SPDX-License-Identifier: Apache-2.0
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 
 #ifndef __BLE_ENVIRONMENTAL_SERVICE_H__
 #define __BLE_ENVIRONMENTAL_SERVICE_H__
 
 #include "ble/BLE.h"
 #include "ble/Gap.h"
 #include "ble/GattServer.h"
 
 #if BLE_FEATURE_GATT_SERVER
 
 /**
 * @class EnvironmentalService
 * @brief BLE Environmental Service. This service provides temperature, humidity and pressure measurement.
 * Service:  https://developer.bluetooth.org/gatt/services/Pages/ServiceViewer.aspx?u=org.bluetooth.service.environmental_sensing.xml
 * Temperature: https://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.temperature.xml
 * Humidity: https://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.humidity.xml
 * Pressure: https://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.pressure.xml
 */
 class EnvironmentalService {
 public:
     typedef int16_t  TemperatureType_t;
     typedef uint16_t HumidityType_t;
     typedef uint32_t PressureType_t;
 
     /**
      * @brief   EnvironmentalService constructor.
      * @param   _ble Reference to BLE device.
      */
     EnvironmentalService(BLE& _ble) :
         ble(_ble),
         temperatureCharacteristic(GattCharacteristic::UUID_TEMPERATURE_CHAR, &temperature),
         humidityCharacteristic(GattCharacteristic::UUID_HUMIDITY_CHAR, &humidity),
         pressureCharacteristic(GattCharacteristic::UUID_PRESSURE_CHAR, &pressure)
     {
         static bool serviceAdded = false; /* We should only ever need to add the information service once. */
         if (serviceAdded) {
             return;
         }
 
         GattCharacteristic *charTable[] = { &humidityCharacteristic,
                                             &pressureCharacteristic,
                                             &temperatureCharacteristic };
 
         GattService environmentalService(GattService::UUID_ENVIRONMENTAL_SERVICE, charTable, sizeof(charTable) / sizeof(charTable[0]));
 
         ble.gattServer().addService(environmentalService);
         serviceAdded = true;
     }
 
     /**
      * @brief   Update humidity characteristic.
      * @param   newHumidityVal New humidity measurement.
      */
     void updateHumidity(HumidityType_t newHumidityVal)
     {
         humidity = (HumidityType_t) (newHumidityVal * 100);
         ble.gattServer().write(humidityCharacteristic.getValueHandle(), (uint8_t *) &humidity, sizeof(HumidityType_t));
     }
 
     /**
      * @brief   Update pressure characteristic.
      * @param   newPressureVal New pressure measurement.
      */
     void updatePressure(PressureType_t newPressureVal)
     {
         pressure = (PressureType_t) (newPressureVal * 10);
         ble.gattServer().write(pressureCharacteristic.getValueHandle(), (uint8_t *) &pressure, sizeof(PressureType_t));
     }
 
     /**
      * @brief   Update temperature characteristic.
      * @param   newTemperatureVal New temperature measurement.
      */
     void updateTemperature(float newTemperatureVal)
     {
         temperature = (TemperatureType_t) (newTemperatureVal * 100);
         ble.gattServer().write(temperatureCharacteristic.getValueHandle(), (uint8_t *) &temperature, sizeof(TemperatureType_t));
     }
 
 private:
     BLE& ble;
 
     TemperatureType_t temperature{};
     HumidityType_t    humidity{};
     PressureType_t    pressure{};
 
     ReadOnlyGattCharacteristic<TemperatureType_t> temperatureCharacteristic;
     ReadOnlyGattCharacteristic<HumidityType_t>    humidityCharacteristic;
     ReadOnlyGattCharacteristic<PressureType_t>    pressureCharacteristic;
 };
 
 #endif // BLE_FEATURE_GATT_SERVER
 
 #endif /* #ifndef __BLE_ENVIRONMENTAL_SERVICE_H__*/
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