microbit-dal/source/ble-services/MicroBitAccelerometerServic...

93 lines
4.4 KiB
C++

/**
* Class definition for the custom MicroBit Accelerometer Service.
* Provides a BLE service to remotely read the state of the accelerometer, and configure its behaviour.
*/
#include "MicroBit.h"
#include "ble/UUID.h"
#include "MicroBitAccelerometerService.h"
/**
* Constructor.
* Create a representation of the AccelerometerService
* @param _ble The instance of a BLE device that we're running on.
*/
MicroBitAccelerometerService::MicroBitAccelerometerService(BLEDevice &_ble) :
ble(_ble)
{
// Create the data structures that represent each of our characteristics in Soft Device.
GattCharacteristic accelerometerDataCharacteristic(MicroBitAccelerometerServiceDataUUID, (uint8_t *)accelerometerDataCharacteristicBuffer, 0,
sizeof(accelerometerDataCharacteristicBuffer), GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY);
GattCharacteristic accelerometerPeriodCharacteristic(MicroBitAccelerometerServicePeriodUUID, (uint8_t *)&accelerometerPeriodCharacteristicBuffer, 0,
sizeof(accelerometerPeriodCharacteristicBuffer),
GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE);
// Initialise our characteristic values.
accelerometerDataCharacteristicBuffer[0] = 0;
accelerometerDataCharacteristicBuffer[1] = 0;
accelerometerDataCharacteristicBuffer[2] = 0;
accelerometerPeriodCharacteristicBuffer = uBit.accelerometer.getPeriod();
GattCharacteristic *characteristics[] = {&accelerometerDataCharacteristic, &accelerometerPeriodCharacteristic};
GattService service(MicroBitAccelerometerServiceUUID, characteristics, sizeof(characteristics) / sizeof(GattCharacteristic *));
ble.addService(service);
accelerometerDataCharacteristicHandle = accelerometerDataCharacteristic.getValueHandle();
accelerometerPeriodCharacteristicHandle = accelerometerPeriodCharacteristic.getValueHandle();
ble.gattServer().write(accelerometerDataCharacteristicHandle,(uint8_t *)accelerometerDataCharacteristicBuffer, sizeof(accelerometerDataCharacteristicBuffer));
ble.gattServer().write(accelerometerPeriodCharacteristicHandle, (const uint8_t *)&accelerometerPeriodCharacteristicBuffer, sizeof(accelerometerPeriodCharacteristicBuffer));
ble.onDataWritten(this, &MicroBitAccelerometerService::onDataWritten);
uBit.MessageBus.listen(MICROBIT_ID_ACCELEROMETER, MICROBIT_ACCELEROMETER_EVT_DATA_UPDATE, this, &MicroBitAccelerometerService::accelerometerUpdate, MESSAGE_BUS_LISTENER_IMMEDIATE);
}
/**
* Callback. Invoked when any of our attributes are written via BLE.
*/
void MicroBitAccelerometerService::onDataWritten(const GattWriteCallbackParams *params)
{
if (params->handle == accelerometerPeriodCharacteristicHandle && params->len >= sizeof(accelerometerPeriodCharacteristicBuffer))
{
accelerometerPeriodCharacteristicBuffer = *((uint16_t *)params->data);
uBit.accelerometer.setPeriod(accelerometerPeriodCharacteristicBuffer);
// The accelerometer will choose the nearest period to that requested that it can support
// Read back the ACTUAL period it is using, and report this back.
accelerometerPeriodCharacteristicBuffer = uBit.accelerometer.getPeriod();
ble.gattServer().write(accelerometerPeriodCharacteristicHandle, (const uint8_t *)&accelerometerPeriodCharacteristicBuffer, sizeof(accelerometerPeriodCharacteristicBuffer));
}
}
/**
* Accelerometer update callback
*/
void MicroBitAccelerometerService::accelerometerUpdate(MicroBitEvent e)
{
if (ble.getGapState().connected)
{
accelerometerDataCharacteristicBuffer[0] = uBit.accelerometer.getX();
accelerometerDataCharacteristicBuffer[1] = uBit.accelerometer.getY();
accelerometerDataCharacteristicBuffer[2] = uBit.accelerometer.getZ();
ble.gattServer().notify(accelerometerDataCharacteristicHandle,(uint8_t *)accelerometerDataCharacteristicBuffer, sizeof(accelerometerDataCharacteristicBuffer));
}
}
const uint8_t MicroBitAccelerometerServiceUUID[] = {
0xe9,0x5d,0x07,0x53,0x25,0x1d,0x47,0x0a,0xa0,0x62,0xfa,0x19,0x22,0xdf,0xa9,0xa8
};
const uint8_t MicroBitAccelerometerServiceDataUUID[] = {
0xe9,0x5d,0xca,0x4b,0x25,0x1d,0x47,0x0a,0xa0,0x62,0xfa,0x19,0x22,0xdf,0xa9,0xa8
};
const uint8_t MicroBitAccelerometerServicePeriodUUID[] = {
0xe9,0x5d,0xfb,0x24,0x25,0x1d,0x47,0x0a,0xa0,0x62,0xfa,0x19,0x22,0xdf,0xa9,0xa8
};