7b5cd47d07
* Set IDF to v3.2 * Remove BLE submodule * Add BLE lib source * Update Camera example to support OV3660
112 lines
3.6 KiB
C++
112 lines
3.6 KiB
C++
/*
|
|
Video: https://www.youtube.com/watch?v=oCMOYS71NIU
|
|
Based on Neil Kolban example for IDF: https://github.com/nkolban/esp32-snippets/blob/master/cpp_utils/tests/BLE%20Tests/SampleNotify.cpp
|
|
Ported to Arduino ESP32 by Evandro Copercini
|
|
updated by chegewara
|
|
|
|
Create a BLE server that, once we receive a connection, will send periodic notifications.
|
|
The service advertises itself as: 4fafc201-1fb5-459e-8fcc-c5c9c331914b
|
|
And has a characteristic of: beb5483e-36e1-4688-b7f5-ea07361b26a8
|
|
|
|
The design of creating the BLE server is:
|
|
1. Create a BLE Server
|
|
2. Create a BLE Service
|
|
3. Create a BLE Characteristic on the Service
|
|
4. Create a BLE Descriptor on the characteristic
|
|
5. Start the service.
|
|
6. Start advertising.
|
|
|
|
A connect hander associated with the server starts a background task that performs notification
|
|
every couple of seconds.
|
|
*/
|
|
#include <BLEDevice.h>
|
|
#include <BLEServer.h>
|
|
#include <BLEUtils.h>
|
|
#include <BLE2902.h>
|
|
|
|
BLEServer* pServer = NULL;
|
|
BLECharacteristic* pCharacteristic = NULL;
|
|
bool deviceConnected = false;
|
|
bool oldDeviceConnected = false;
|
|
uint32_t value = 0;
|
|
|
|
// See the following for generating UUIDs:
|
|
// https://www.uuidgenerator.net/
|
|
|
|
#define SERVICE_UUID "4fafc201-1fb5-459e-8fcc-c5c9c331914b"
|
|
#define CHARACTERISTIC_UUID "beb5483e-36e1-4688-b7f5-ea07361b26a8"
|
|
|
|
|
|
class MyServerCallbacks: public BLEServerCallbacks {
|
|
void onConnect(BLEServer* pServer) {
|
|
deviceConnected = true;
|
|
BLEDevice::startAdvertising();
|
|
};
|
|
|
|
void onDisconnect(BLEServer* pServer) {
|
|
deviceConnected = false;
|
|
}
|
|
};
|
|
|
|
|
|
|
|
void setup() {
|
|
Serial.begin(115200);
|
|
|
|
// Create the BLE Device
|
|
BLEDevice::init("ESP32");
|
|
|
|
// Create the BLE Server
|
|
pServer = BLEDevice::createServer();
|
|
pServer->setCallbacks(new MyServerCallbacks());
|
|
|
|
// Create the BLE Service
|
|
BLEService *pService = pServer->createService(SERVICE_UUID);
|
|
|
|
// Create a BLE Characteristic
|
|
pCharacteristic = pService->createCharacteristic(
|
|
CHARACTERISTIC_UUID,
|
|
BLECharacteristic::PROPERTY_READ |
|
|
BLECharacteristic::PROPERTY_WRITE |
|
|
BLECharacteristic::PROPERTY_NOTIFY |
|
|
BLECharacteristic::PROPERTY_INDICATE
|
|
);
|
|
|
|
// https://www.bluetooth.com/specifications/gatt/viewer?attributeXmlFile=org.bluetooth.descriptor.gatt.client_characteristic_configuration.xml
|
|
// Create a BLE Descriptor
|
|
pCharacteristic->addDescriptor(new BLE2902());
|
|
|
|
// Start the service
|
|
pService->start();
|
|
|
|
// Start advertising
|
|
BLEAdvertising *pAdvertising = BLEDevice::getAdvertising();
|
|
pAdvertising->addServiceUUID(SERVICE_UUID);
|
|
pAdvertising->setScanResponse(false);
|
|
pAdvertising->setMinPreferred(0x0); // set value to 0x00 to not advertise this parameter
|
|
BLEDevice::startAdvertising();
|
|
Serial.println("Waiting a client connection to notify...");
|
|
}
|
|
|
|
void loop() {
|
|
// notify changed value
|
|
if (deviceConnected) {
|
|
pCharacteristic->setValue((uint8_t*)&value, 4);
|
|
pCharacteristic->notify();
|
|
value++;
|
|
delay(10); // bluetooth stack will go into congestion, if too many packets are sent, in 6 hours test i was able to go as low as 3ms
|
|
}
|
|
// disconnecting
|
|
if (!deviceConnected && oldDeviceConnected) {
|
|
delay(500); // give the bluetooth stack the chance to get things ready
|
|
pServer->startAdvertising(); // restart advertising
|
|
Serial.println("start advertising");
|
|
oldDeviceConnected = deviceConnected;
|
|
}
|
|
// connecting
|
|
if (deviceConnected && !oldDeviceConnected) {
|
|
// do stuff here on connecting
|
|
oldDeviceConnected = deviceConnected;
|
|
}
|
|
}
|