Adafruit Python BluefruitLE works on Raspberry Pi.

Introduction

We distributed the first stray badge in a limited quantity in Technical Book 7, but we received a comment from the purchaser about "Integration with Raspberry Pi", so we decided to make it an article in Technical Book 8. .. Anyway, with a development policy that works with the same library and source code on both Mac and Linux (Raspberry Pi), make a note of the problems you faced and how to solve them.

After all it did not move

Since there was a sample code (C) for ESP32, a sample code (JavaScript) using the Web Bluetooth API of the Chrome browser, and a message display program (Python) for the USB-HID version LED Badge in Technical Book 7, node.js I decided to develop with Python.

environment

--Mac: macOS Mojave version 10.14.6 (18G1012) + Xcode 11.3 (11C29)

• Linux: Raspberry Pi Zero W / Raspberry Pi 3 Model B+ (Raspbian GNU/Linux 10 buster)

Adafruit Python BluefruitLE library

node.js worked fine with the noble library and Python worked fine on the Mac with Adafruit Python BluefruitLE, but on the Raspberry Pi " Adafruit Python Bluefruit LE didn't work ", and as expected, it didn't work either.

BlueZ (5.38) and later patches

As we investigated, Linux uses BlueZ (5.50), and since BlueZ (5.38), the specifications of D-Bus Object Manager have changed, so it was necessary to apply a patch. As of January 26, 2020, it was not merged into the original home and should be resolved by: (reference) Fixed incompatibility with BlueZ version >= 5.38

environment

--Linux: Python 3.7.3 + BlueZ (5.50) + Adafruit Python BluefruitLE (donatieng patch)

It worked

There are two solutions.

--If you already have the Adafruit Python BluefruitLE library installed, apply the patch manually. Alternatively, uninstall and install the patched Adafruit Python BluefruitLE library. --If you have not already installed the Adafruit Python BluefruitLE library, install the patched Adafruit Python BluefruitLE library.

Manually patch

$ cd /usr/local/lib/python3.7/dist-packages/Adafruit_BluefruitLE/bluez_dbus/
$ sudo mv gatt.py gatt.py_org
$ sudo wget https://raw.githubusercontent.com/donatieng/Adafruit_Python_BluefruitLE/master/Adafruit_BluefruitLE/bluez_dbus/gatt.py

Uninstall the Adafruit Python BluefruitLE library

$ sudo pip3 uninstall Adafruit-BluefruitLE

Installing the patched Adafruit Python BluefruitLE library

$ git clone https://github.com/donatieng/Adafruit_Python_BluefruitLE
$ cd Adafruit_Python_BluefruitLE/
$ sudo python3 setup.py install

Summary

Technical Book 8 is being written with the theme of "hacking light and sound"! (As of January 27, 2020) The store will open on the second day, "Ka 40", so let's meet on the day! !!