Diff: microbit/microbit-dal/source/bluetooth/MicroBitAccelerometerService.cpp

Revision:

0:b9164b348919

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/microbit/microbit-dal/source/bluetooth/MicroBitAccelerometerService.cpp	Mon Oct 17 12:41:20 2016 +0000
@@ -0,0 +1,121 @@
+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 British Broadcasting Corporation.
+This software is provided by Lancaster University by arrangement with the BBC.
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+*/
+
+/**
+  * 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 "MicroBitConfig.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.
+  * @param _accelerometer An instance of MicroBitAccelerometer.
+  */
+MicroBitAccelerometerService::MicroBitAccelerometerService(BLEDevice &_ble, MicroBitAccelerometer &_accelerometer) :
+        ble(_ble), accelerometer(_accelerometer)
+{
+    // 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 = accelerometer.getPeriod();
+
+    // Set default security requirements
+    accelerometerDataCharacteristic.requireSecurity(SecurityManager::MICROBIT_BLE_SECURITY_LEVEL);
+    accelerometerPeriodCharacteristic.requireSecurity(SecurityManager::MICROBIT_BLE_SECURITY_LEVEL);
+
+    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);
+
+    if (EventModel::defaultEventBus)
+        EventModel::defaultEventBus->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);
+        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 = accelerometer.getPeriod();
+        ble.gattServer().write(accelerometerPeriodCharacteristicHandle, (const uint8_t *)&accelerometerPeriodCharacteristicBuffer, sizeof(accelerometerPeriodCharacteristicBuffer));
+    }
+}
+
+/**
+  * Accelerometer update callback
+  */
+void MicroBitAccelerometerService::accelerometerUpdate(MicroBitEvent)
+{
+    if (ble.getGapState().connected)
+    {
+        accelerometerDataCharacteristicBuffer[0] = accelerometer.getX();
+        accelerometerDataCharacteristicBuffer[1] = accelerometer.getY();
+        accelerometerDataCharacteristicBuffer[2] = 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
+};