UberVestService.h

00001 class UberVestService {
00002 public:
00003     const static uint16_t UBER_VEST_SERVICE_UUID   = 0xB000;
00004     const static uint16_t ECG_CHARACTERISTIC_UUID  = 0xB002;
00005     const static uint16_t TEMP_CHARACTERISTIC_UUID = 0xB003;
00006 
00007     UberVestService(BLE &_ble, int8_t ecgInitial, uint8_t tempInitial) :
00008         ble(_ble),
00009         ecgState(ECG_CHARACTERISTIC_UUID, &ecgInitial, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY),
00010         tempState(TEMP_CHARACTERISTIC_UUID, &tempInitial, 5, 5, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY)
00011     {
00012         GattCharacteristic *charTable[] = {&ecgState, &tempState};
00013         GattService         uberVestService(UberVestService::UBER_VEST_SERVICE_UUID, charTable, sizeof(charTable) / sizeof(GattCharacteristic *));
00014         
00015         ble.gattServer().addService(uberVestService);
00016     }
00017 
00018     void updateEcg(int8_t value) {
00019         ble.gattServer().write(ecgState.getValueHandle(), (uint8_t *)&value, sizeof(int8_t));
00020     }
00021     
00022     // The following adapted from https://developer.mbed.org/users/donalm/code/BLE_Health_Thermometer_Blog/file/f11df1469db2/main.cpp:
00023     void updateTemp(float value) {
00024         uint8_t  thermTempPayload[5] = { 0, 0, 0, 0, 0 };
00025         uint32_t temp_ieee11073      = quick_ieee11073_from_float(value);
00026         
00027         memcpy(thermTempPayload + 1, &temp_ieee11073, 4);
00028         
00029         ble.gattServer().write(tempState.getValueHandle(), thermTempPayload, sizeof(thermTempPayload));
00030     }
00031  
00032     /**
00033      * @brief A very quick conversion between a float temperature and 11073-20601 FLOAT-Type.
00034      * @param temperature The temperature as a float.
00035      * @return The temperature in 11073-20601 FLOAT-Type format.
00036      */
00037     uint32_t quick_ieee11073_from_float(float temperature)
00038     {
00039         uint8_t  exponent = 0xFF; //exponent is -1
00040         uint32_t mantissa = (uint32_t)(temperature*10);
00041         
00042         return ( ((uint32_t)exponent) << 24) | mantissa;
00043     }
00044 
00045 private:
00046     BLE &ble;
00047     ReadOnlyGattCharacteristic<int8_t> ecgState;
00048     GattCharacteristic                 tempState;
00049 };