3.2 KiB
Overview
This is a C++ BLE library for the ESP32 that uses the NimBLE host stack instead of bluedroid.
The aim is to maintain, as much as reasonable, the original bluedroid C++ API while adding new features
and making improvements in performance, resource use and stability.
Testing shows a nearly 50% reduction in flash use and approx. 100kB less ram consumed vs the original!
Your results may vary
What is NimBLE?
NimBLE is a completely open source Bluetooth Low Energy stack produced by Apache.
It is more suited to resource constrained devices than bluedroid and has now been ported to the ESP32 by Espressif.
Arduino Installation
Download as .zip and extract to Arduino/libraries folder, or in Arduino IDE from Sketch menu -> Include library -> Add .Zip library.
#include "NimBLEDevice.h" at the beginning of your sketch.
Tested and working with esp32-arduino v1.0.2 and 1.0.4 in Arduino IDE v1.8.12 and platform IO.
ESP-IDF Installation
v4.0+
Download as .zip and extract or clone into the components folder in your esp-idf project.
Run menuconfig, go to Component config->Bluetooth enable Bluetooth and in Bluetooth host NimBLE.
Configure settings in NimBLE Options.
#include "NimBLEDevice.h" in main.cpp.
Call NimBLEDevice::init(""); in app_main.
v3.2 & v3.3
The NimBLE component does not come with these versions of IDF.
A backport that works in these versions has been created and is available here.
Download or clone that repo into your project/components folder and run menuconfig.
Configure settings in main menu -> NimBLE Options.
#include "NimBLEDevice.h" in main.cpp.
Call NimBLEDevice::init(""); in app_main.
Using
This library is intended to be compatible with the original ESP32 BLE functions and types with minor changes.
See: Breaking API Changes vs Original for details.
Also see Improvements_and_updates for information about non-breaking changes.
Arduino
See the Refactored_original_examples in the examples folder for highlights of the differences with the original library.
More advanced examples highlighting many available features are in examples/NimBLE_Server, NimBLE_Client.
Beacon examples provided by beegee-tokyo are in examples/BLE_Beacon_Scanner, BLE_EddystoneTLM_Beacon, BLE_EddystoneURL_Beacon.
Change the settings in the nimconfig.h file to customize NimBLE to your project, such as increasing max connections (default == 3).
Acknowledgments
- nkolban and chegewara for the original esp32 BLE library this project was derived from.
- beegee-tokyo for contributing your time to test/debug and contributing the beacon examples.
- Jeroen88 for the amazing help debugging and improving the client code.