Adafruit Bluetooth LE Sensor Nodes User Manual

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Bluetooth LE Sensor Nodes to Raspberry Pi WiFi Bridge

Created by John Park

Last updated on 2021-04-16 12:38:58 PM EDT

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Guide Contents

Guide Contents Overview

Parts Optional Parts

Prepare the CLUE

Libraries Text Editor Code.py How It Works Measurements

Prepare the Feather Sense

Libraries Text Editor Code.py How It Works Measurements Other Boards

Raspberry Pi Quick Setup

SD Card Prep Power to the Pi Ping SSH Change the Password! Rename the Pi Update Application List Software Setup

Make sure you're using Python 3!

Install Blinka

Install Pi Bridge Software BLE Support

Adafruit Blinka BLEio Bluetooth Group

Install Python libraries

Add Examples Adafruit IO Shhh Secrets Service Identity Launch BroadcastNet Bridge

BroadcastNet on AIO

Adafruit IO Getting Started Renaming AIO Feeds Dashboard Setup Blocks Measurement List

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Overview

Use sensor-packed Bluefruit boards and a Raspberry Pi to build a network of sensors that send data to Adafruit IO!

This project takes advantage of CircuitPython running on the Feather Bluefruit Sense (https://adafru.it/JA1) and CLUE boards (https://adafru.it/Jkd) (any nRF52840 Adafruit board will work (https://adafru.it/JA2)) and Python running on the Raspberry Pi.

The Pi receives advertised BLE sensor data from the Feather and CLUE and then sends that data over

WiFi or Ethernet to your Adafruit IO feed.

Its a super easy way to make a wireless sensor node, using the built in wireless/networking capabilities of the Raspberry Pi!

Parts

You can use any of the Adafruit nRF52840 boards and sensors you like. We'll show how it works with the Feather Sense and CLUE boards, since they pack so many sensors right on board.

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Adafruit Feather nRF52840 Sense

The Adafruit Feather Bluefruit Sense takes our popular Feather nRF52840 Express and adds a smorgasbord of sensors... $32.50 In Stock

Your browser does not support the video tag. Adafruit CLUE - nRF52840 Express with Bluetooth LE

Do you feel like you just don't have a CLUE? Well, we can help with that - get a CLUE here at Adafruit by picking up this sensor-packed development board. We wanted to build some... $39.95 In Stock

Add to Cart

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Raspberry Pi 4 Model B

The Raspberry Pi 4 Model B is the newest Raspberry Pi computer made, and the Pi Foundation knows you can always make a good thing better! And what could make the Pi 4 better... Out of Stock

Official Raspberry Pi Power Supply 5.1V 3A with USB C

Add from Store

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The official Raspberry Pi USB-C power supply is here! And of course, we have 'em in classic Adafruit black! Super fast with just the right amount of cable length to get your Pi 4... $7.95 In Stock

Raspberry Pi 3 - Model B+ - 1.4GHz Cortex-A53 with 1GB RAM

The Raspberry Pi 3 Model B is the most popular Raspberry Pi computer made, and the Pi Foundation knows you can always make a good thing better! And what could make the Pi 3... $35.00 In Stock

Add to Cart

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USB cable - USB A to Micro-B

This here is your standard A to micro-B USB cable, for USB 1.1 or 2.0. Perfect for connecting a PC to your Metro, Feather, Raspberry Pi or other dev-board or... $2.95 In Stock

Add to Cart

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Raspberry Pi Zero W Basic Pack - Includes Pi Zero W

Remember those cereal commercials that would always say, "part of a complete breakfast"? Well the Pi Zero's a lot like that bowl of cereal - while it's... $24.50 In Stock

Optional Parts

If you want to use, say, a Feather nRF52840 plus some plug-in STEMMA QT breakouts, here are some great options:

Adafruit Feather nRF52840 Express

The Adafruit Feather nRF52840 Express is the new Feather family member with Bluetooth Low Energy and native USB support featuring the nRF52840! It's... Out of Stock

Add to Cart

Out of

Stock

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SparkFun Qwiic / Stemma QT FeatherWing (Shield for Thing Plus)

The SparkFun Qwiic FeatherWing (Shield for Thing Plus) provides an easy-to-assemble way to add the $4.95 In Stock

STEMMA QT / Qwiic JST SH 4-pin Cable - 100mm Long

Add to Cart

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This 4-wire cable is a little over 100mm / 4" long and fitted with JST-SH female 4-pin connectors on both ends. Compared with the chunkier JST-PH these are 1mm pitch instead of... $0.95 In Stock

STEMMA QT / Qwiic JST SH 4-Pin Cable

This 4-wire cable is 50mm / 1.9" long and fitted with JST SH female 4-pin connectors on both ends. Compared with the chunkier JST PH these are 1mm pitch instead of 2mm, but... Out of Stock

Add to Cart

Out of

Stock

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Adafruit DPS310 Precision Barometric Pressure / Altitude Sensor

How high are you right now? If you had a precision altitude sensor, you would know for sure! The DPS310 sensor from Infineon a high-precision barometric sensor, perfect for measuring... $6.95 In Stock

Add to Cart

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Adafruit PCT2075 Temperature Sensor - STEMMA QT / Qwiic

The Adafruit PCT2075 Temperature Sensor is a 'code compatible' drop-in replacement for a very... $4.95 In Stock

Adafruit VCNL4040 Proximity and Lux Sensor - STEMMA QT / Qwiic

The VCNL4040 is a handy two-in-one sensor, with a proximity sensor that works from 0 to 200mm (about

7.5 inches) and light sensor with range of 0.0125 to 6553 lux.We've all... $5.95 In Stock

Add to Cart

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Adafruit APDS9960 Proximity, Light, RGB, and Gesture Sensor

This breakout is chock full o' sensors! Add basic gesture sensing, RGB color sensing, proximity sensing, or ambient light sensing to your project with the Adafruit... $7.50 In Stock

Add to Cart

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Adafruit BMP280 I2C or SPI Barometric Pressure & Altitude Sensor

Bosch has stepped up their game with their new BMP280 sensor, an environmental sensor with temperature, barometric pressure that is the next generation upgrade to the... $9.95 In Stock

Adafruit BME280 I2C or SPI Temperature Humidity Pressure Sensor

Bosch has stepped up their game with their new BME280 sensor, an environmental sensor with temperature, barometric pressure and humidity! This sensor is great for all sorts... $14.95 In Stock

Add to Cart

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Prepare the CLUE

We'll set up the CLUE board to act as a sensor for the BroadcastNet.

First, set up CircuitPython on the CLUE following the instructions on this page (https://adafru.it/Jab).

Libraries

Next, install the libraries needed. This guide

page (https://adafru.it/Jb9) will show you where to download

them.

You'll need the following libraries for this project:

adafruit_apds9960 adafruit_ble adafruit_ble_broadcastnet adafruit_bmp280.mpy adafruit_bus_device adafruit_clue.mpy adafruit_register adafruit_lis3mdl.mpy adafruit_lsm6ds adafruit_sht31d.mpy neopixel.mpy

Text Editor

Adafruit recommends using the Mu editor for using your CircuitPython code with the CLUE board. You can get more info in this guide (https://adafru.it/ANO).

Alternatively, you can use any text editor that saves files.

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 Code.py

Copy the code shown below, paste it into Mu. Save the code from Mu to the CLUE's CIRCUITPY drive as

code.py

Temporarily unable to load content:

How It Works

When this code runs on the CLUE board, it'll first import the time , clue , and adafruit_ble_broadcastnet libraries.

Then, it will print the unique ID for the board based on the board's BLE adapter's MAC address. This address will be used when messages are sent so there won't be any clashes when multiple microcontroller boards are in range of the BroadcastNet base station.

 NOTE: this is not a secure connection, so think of this system as "broadcasting" in the truest sense of the word!

import time from adafruit_clue import clue import adafruit_ble_broadcastnet

print("This is BroadcastNet CLUE sensor:", adafruit_ble_broadcastnet.device_address)

Measurements

Next, we will have the main loop of the program. In it, the board sends out an advertisement to alert the base station central device that it is there.

Next we collect the different sensor readings such as measurement.temperature = clue.temperature

We then print the combined measurement to the screen and broadcast it.

Finally, the code will sleep for a certain amount of time. Depending on your needs this can be as frequent as every two seconds if sending a single data point to Adafruit IO* (or every one second to AIO+) to many minutes or hours between sensor measurement broadcasts. In this case, it is pausing for 60 seconds between broadcasts.

*The data limit on Adafruit IO is 30 data points per minute and 60/min on Adafruit IO+)

 Even if you only measure one data point, there will always also be an additional data point sent for the 'missed-message-count' value used as a type of error check. This counts toward the rate limit on AIO.

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while True: measurement = adafruit_ble_broadcastnet.AdafruitSensorMeasurement()

measurement.temperature = clue.temperature measurement.pressure = clue.pressure measurement.relative_humidity = clue.humidity measurement.acceleration = clue.acceleration measurement.magnetic = clue.magnetic

print(measurement) adafruit_ble_broadcastnet.broadcast(measurement) time.sleep(60)

Once we set up the Raspberry Pi to act as a Broadcastnet base station, the CLUE sensor data will be able to make its way all the way to Adafruit IO!

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Prepare the Feather Sense

We'll set up the Feather Sense board to act as a sensor for the BroadcastNet.

First, set up CircuitPython on the Feather Sense following the instructions on this

page (https://adafru.it/EwP). NOTE: This board is so new, the instructions are actually for the regular

nRF52840 Feather, so when you go to the CircuitPython.org download page, be sure to use the download

for the Sense board (https://adafru.it/JqE) instead!

Libraries

Next, install the libraries needed. This guide

page (https://adafru.it/ABU) will show you where to download

them.

You'll need the following libraries for this project:

adafruit_apds9960 adafruit_ble adafruit_ble_broadcastnet adafruit_bmp280 adafruit_bus_device adafruit_register adafruit_lis3mdl adafruit_lsm6ds adafruit_sht31d neopixel.mpy

Text Editor

Adafruit recommends using the Mu editor for using your CircuitPython code with the Feather Sense board. You can get more info in this guide (https://adafru.it/ANO).

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Alternatively, you can use any text editor that saves files.

 Code.py

Copy the code shown below, paste it into Mu. Save the code from Mu to the Feather's CIRCUITPY drive as

code.py

"""This uses the Feather Sense as a Bluetooth LE sensor node."""

import time import adafruit_ble_broadcastnet import board import adafruit_lsm6ds # accelerometer import adafruit_sht31d # humidity sensor import adafruit_bmp280 # barometric sensor import adafruit_lis3mdl # magnetic sensor

i2c = board.I2C()

sense_accel = adafruit_lsm6ds.LSM6DS33(i2c) sense_humid = adafruit_sht31d.SHT31D(i2c) sense_barometric = adafruit_bmp280.Adafruit_BMP280_I2C(i2c) sense_magnet = adafruit_lis3mdl.LIS3MDL(i2c)

print("This is BroadcastNet Feather Sense sensor:", adafruit_ble_broadcastnet.device_address)

while True: measurement = adafruit_ble_broadcastnet.AdafruitSensorMeasurement()

measurement.temperature = sense_barometric.temperature measurement.pressure = sense_barometric.pressure measurement.relative_humidity = sense_humid.relative_humidity measurement.acceleration = sense_accel.acceleration measurement.magnetic = sense_magnet.magnetic

# print(measurement) adafruit_ble_broadcastnet.broadcast(measurement) time.sleep(60)

How It Works

When this code runs on the Feather Sense board, it'll first import the time , board , and

adafruit_ble_broadcastnet libraries, along with the library for each sensor in the board that we're using.

Next, I2C is instantiated on the board for communications with the sensors.

We create an object (with a nice name!) for each sensor as well, and instruct them to use I2C.

Then, it will print the unique ID for the board based on the board's BLE adapter MAC address. This address will be used when messages are sent, so there won't be any clashes when multiple microcontroller boards are in range of the BroadcastNet base station.

 NOTE: this is not a secure connection, so think of this system as "broadcasting" in the truest sense of the word!

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i2c = board.I2C()

sense_accel = adafruit_lsm6ds.LSM6DS33(i2c) sense_humid = adafruit_sht31d.SHT31D(i2c) sense_barometric = adafruit_bmp280.Adafruit_BMP280_I2C(i2c) sense_magnet = adafruit_lis3mdl.LIS3MDL(i2c)

print("This is BroadcastNet Feather Sense sensor:", adafruit_ble_broadcastnet.device_address)

Measurements

Next, we will have the main loop of the program. In it, the board sends out an advertisement to alert the base station central device that it is there.

Next we collect the different sensor readings such as measurement.temperature =

sense_barometric.temperature (we're using the temperature sensor that is built onto the barometric pressure

sensor package).

We then broadcast the combined measurement over BLE.

Finally, the code will sleep for a certain amount of time. Depending on your needs, this can be as frequent as every two seconds, if sending a single data point to Adafruit IO* (or every one second to AIO+) to many minutes or hours between sensor measurement broadcasts. In this case, it is pausing for 60 seconds between broadcasts.

*The data limit on Adafruit IO is 30 data points per minute and 60/min on Adafruit IO+)

measurement = adafruit_ble_broadcastnet.AdafruitSensorMeasurement()

# print(measurement) adafruit_ble_broadcastnet.broadcast(measurement) time.sleep(60)

Once we set up the Raspberry Pi to act as a BroadcastNet base station, the CLUE sensor data will be able to make its way all the way to Adafruit IO!

Other Boards

If you choose to use a different Adafruit nRF52840 board and external sensors, the setup will be very nearly the same. Check the guide for the board and sensors for the particulars.

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Raspberry Pi Quick Setup

This quick-start guide will get you ready to connect and run all sorts of Adafruit projects on your Raspberry Pi computer

You will need:

A modern Raspberry Pi computer (https://adafru.it/ejq), we recommend the 'full' size Pi 3 B+ and later,

that come with Ethernet and WiFi built in Matching power supply (USB C type for Pi 4 and later (https://adafru.it/FQQ), or Micro USB type for Pi

3 B+, Pi Zeros (https://adafru.it/e5A) or earlier) 8 GB or larger micro SD card (https://adafru.it/JA0) and USB reader/writer

SD Card Prep

First we need to perform the basic set up the Raspberry Pi. These are the first steps:

download the latest Raspbian desktop operating system burn the OS to an SD card enable SSH add WiFi settings and credentials

For details on doing these things, follow the first four pages of this guide (https://adafru.it/DQA) to get your Pi setup with Raspbian Lite (for 'headless' or remote operation) or NooBs (for graphical / desktop use), WiFi, and ssh enabled.

Once the SD card is prepared, come back here so we can continue.

Power to the Pi

Safely eject the SD card from your main computer. Then, with the Pi unplugged from power, insert the SD card into the Pi's SD card slot.

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Then, plug in the power to the Pi. You should see some LEDs light up.

From here forward, we'll be connecting to the Pi remotely from our main computer. Make sure your computer is on the same WiFi network as the Pi.

Ping

After a minute or two, you can try and ping the Pi to see if it has connected to your network. Open a terminal on your computer, such as Terminal.app on a mac (Windows users will require some additional setup. Read here (https://adafru.it/q1e)), and type this and press return:

ping -c 3 raspberrypi.local

You should see an output similar to this:

jep@machine ~ % ping -c 3 raspberrypi.local PING raspberrypi.local (192.168.1.68): 56 data bytes 64 bytes from 192.168.1.68: icmp_seq=0 ttl=64 time=14.993 ms 64 bytes from 192.168.1.68: icmp_seq=1 ttl=64 time=20.565 ms 64 bytes from 192.168.1.68: icmp_seq=2 ttl=64 time=50.571 ms

--- raspberrypi.local ping statistics --3 packets transmitted, 3 packets received, 0.0% packet loss round-trip min/avg/max/stddev = 14.993/28.710/50.571/15.625 ms

This tells us that the Pi is on the network, and has an address of 192.168.1.68.

SSH

We can now connect to it through the secure shell (SSH) so we can control it remotely.

Here's some great info on SSH (https://adafru.it/vbC) from the Raspberry Pi Foundation.

Type the following in your terminal:

ssh pi@raspberrypi.local

ssh pi@192.168.1.68 (or whatever address you saw returned earlier when you pinged it.)

You may see a message warning you that the authenticity of the host can't be established, Are you sure

you want to continue connecting (yes/no)?

To this question you can reply by typing yes and pressing return. This will add the Pi to your list of known hosts and should not pop up again with this question.

You will now see the password prompt for the Pi:

pi@raspberrypi.local's password:

Go ahead and type in the default password, which is: raspberry

Change the Password!

You will now be logged into the Pi over ssh! There will be a warning about changing your password from the default and instructions on how to do so. Do it now! Type passwd , hit return and follow the instructions

to create a new, secure, non-default password!

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Rename the Pi

You may end up with multiple Pi computers on your network, which can get confusing if they are all named raspberrypi. To rename this one for this project, type in sudo raspi-config and press return.

 sudo? What's sudo? It stands for "superuser do", and it's a program that lets you run powerful commands which are normally restricted for reasons of safety and security. Or just to prevent accidents!

Use the arrows and enter key on your keyboard to navigate. Pick 2 Network Options and press return on your keyboard.

Then, pick N1 Hostname.

Enter a new hostname -- I typed raspberrypiBlinkaBridge

Use the Tab key to get to the <Ok> button and press return.

Press tab twice to get to the <Finish> button and press return.

Now, we'll restart the Pi to make the changed host name show up on the network by typing sudo reboot and pressing return.

Note, this will close the SSH session. After the Pi restarts, wait about a minute, and then reconnect over SSH. This time, you'll use the new name: ssh pi@raspberrypiBlinkaBridge

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Update Application List

Once logged into the Pi, we'll do some software updates to make sure we have the latest of everything.

 We really really recommend the lastest Raspbian only. If you have an older Raspbian install, run "sudo apt-get update" and "sudo apt-get upgrade" to get the latest OS!

Type:

sudo apt-get update

And then press return. This will run for a little bit as it reads the available package lists, and then finish, reporting that it is done.

You can now apply any of these changes by typing:

sudo apt-get upgrade

Type Y and press enter to continue.

Software Setup

Now that the Pi is updated and renamed on the network, we'll make sure we have Python 3 setup, as

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Python 2 is no longer used or supported.

pip3, is the software package installer we'll use. Let's upgrade it to the latest version with this command:

sudo pip3 install --upgrade setuptools

If above doesn't work try

sudo apt-get install python3-pip

Once that has finished you'll be returned to the prompt.

Make sure you're using Python 3!

The default Python on your computer may not be Python 3. Python 2 is officially discontinued and all our libraries are Python 3 only.

We'll be using python3 and pip3 in our commands, use those versions of Python and pip to make sure you're using 3 and not 2.

Install Blinka

Blinka is the software that allows us to run CircuitPython and its libraries on Linux. You can read more

about it here (https://adafru.it/EQa).

To install blinka, type:

sudo pip3 install adafruit-blinka

That's it! You can reboot again if you like.

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Install Pi Bridge Software BLE Support

Next we'll set up BLE support with the BlueZ Bluetooth protocol stack. Type this and hit return:

sudo apt-get install bluez-hcidump

Adafruit Blinka BLEio

"Old MacDonald had a snake, BLEeeee-iiiiii-BLEeeee-iiiiii-oooooo!"

Next, we'll install the Adafruit Blinka bleio library, which is required for CircuitPython BLE to work properly.

In the ssh terminal type:

pip3 install adafruit-blinka-bleio

Bluetooth Group

In order to have the Pi scan for BLE devices we need to increase the permissions granted to the pi user.

To add the user to the bluetooth group do:

sudo usermod -a -G bluetooth pi

(Or, whatever your username is if not the default.)

Now, the pi user won't actually have these new permissions until the next time we log in, so type exit and then re-login to the ssh with

ssh pi@raspberrypiblinkabridge.local

Enter your password when promted, then you can check the groups the pi user is in by typing:

groups

pi@raspberrypiBlinkaBridge:~ $ groups pi adm dialout cdrom sudo audio video plugdev games users input netdev bluetooth gpio i2c spi

Now, we'll set permissions so that we can do comprehensive BLE scanning.

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Type the following lines into the ssh terminal, pressing enter after each one:

sudo chown :bluetooth /usr/bin/hcidump /usr/bin/hcitool sudo chmod o-x /usr/bin/hcidump /usr/bin/hcitool sudo setcap 'cap_net_raw,cap_net_admin+eip' /usr/bin/hcitool sudo setcap 'cap_net_raw,cap_net_admin+eip' /usr/bin/hcidump

Install Python libraries

Now you're ready to install the Python support library (https://adafru.it/Jra) for the BLE BroadcastNet bridge. Run the following command to install it:

pip3 install adafruit-circuitpython-ble-broadcastnet

Add Examples

Let's add some example code to try by cloning a Git repository locally.

Type cd to go to your home directory on the Pi.

Note, you can type pwd (print working directory) to see where you are at any time:

pi@raspberrypiBlinkaBridge:~ $ pwd /home/pi

Here we will clone the example directory. Type:

git clone https://github.com/adafruit/Adafruit_CircuitPython_BLE_BroadcastNet.git

Once it finishes copying the files, you can have a look. Go to the directory by typing cd

Adafruit_CircuitPython_BLE_BroadcastNet (Hint, you can press Tab to complete that long directory name

after you type a couple of the letters).

Check out the contents by typing ls -1

pi@raspberrypiBlinkaBridge:~/Adafruit_CircuitPython_BLE_BroadcastNet $ ls -1 adafruit_ble_broadcastnet.py CODE_OF_CONDUCT.md docs examples LICENSE README.rst requirements.txt setup.py

The adafruit_ble_broadcastnet.py file is the Python library we'll be using when we run the code. The code we want to run on the Pi is inside the /examples directory. Let's go there by typing:

cd ./examples/

ble_broadcastnet_blinka_bridge.py is the one we'll run on the Pi (after setting up the secrets.py file below), while the others are examples we can run on different microcontrollers such as the CLUE, Circuit Playground Bluefruit, Feather nRF52840, Feather Sense, and ItsyBitsy nRF52840.

ble_broadcastnet_battery_level_neopixel.py

ble_broadcastnet_battery_level.py

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ble_broadcastnet_cpb.py

ble_broadcastnet_expo_backoff.py

ble_broadcastnet_multisensor.py

ble_broadcastnet_simpletest.py

Adafruit IO

In order to used the Adafruit IO Internet of Things service (which is absolutely free to use) you'll need to log in with your Adafruit account. If you don't already have an Adafruit login, create one

here (https://adafru.it/dAQ).

If you haven't used Adafruit IO before, check out this guide for more info (https://adafru.it/Ef8).

Once you have logged into your account, there are two pieces of information you'll need to place in your secrets.py file: Adafruit IO username , and Adafruit IO key . Head to io.adafruit.com (https://adafru.it/fsU) and

simply click the View AIO Key link on the left hand side of the Adafruit IO page to get this information.

Shhh Secrets

The ble_broadcastnet_blinka_bridge.py program will need to authenticate your Adafruit IO credentials in order to run. So, we'll create a file called secrets.py to contain this info.

Inside is a Python dictionary named secrets with a line for each entry. Each entry has an entry name (say

'aio_username' ) and then a colon to separate it from the entry key 'daphne_von_person'

secrets = { 'aio_username' : '_your_aio_username_', 'aio_key' : '_your_big_huge_super_long_aio_key_' }

 Don't share your secrets.py - keep that out of GitHub, Discord or other project-sharing sites.

Use a text editor to create and save this file into the /Adafruit_CircuitPython_BLE_Broadcast/examples directory. Since you are ssh'd into the Pi, the easiest way to do this is with the nano text editor. Type:

nano secrets.py

In the nano editor that launches, copy and paste the secrets text from above, replacing the username and key with your own, then save & exit.

Your /examples directory should now look like this:

ble_broadcastnet_battery_level_neopixel.py

ble_broadcastnet_battery_level.py

ble_broadcastnet_blinka_bridge.py

ble_broadcastnet_cpb.py

ble_broadcastnet_expo_backoff.py

ble_broadcastnet_multisensor.py

ble_broadcastnet_simpletest.py

secrets.py

Service Identity

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Next, we'll install the service_identity module, which is used behind the scenes for certificate verification. Type this into the ssh terminal and press return:

pip3 install service_identity

Launch BroadcastNet Bridge

We're now ready to run the broadcast bridge software on the Pi! When this runs it will look for BLE sensors, collect their message data, and then send it to your Adafruit IO account as a uniquely named feed.

To run it, type this in the ssh shell and press return:

python3 ble_broadcastnet_blinka_bridge.py

If your Feather Sense and/or CLUE boards you set up earlier are powered on and within range, you will start to see the measurement values being received successfully:

bridge-dca63202680a-sensor-fdc492775544 [{'key': 'missed-message-count', 'value': 0}, {'key': 'acceleration-0-x', ' value': -5.6099700927734375}, {'key': 'acceleration-0-y', 'value': 2.15712833404541}, {'key': 'acceleration-0-z', ' value': 7.956132888793945}, {'key': 'pressure-0', 'value': 992.184814453125}] Done logging measurement to IO. Took 0.628571397000087 seconds

bridge-dca63202680a-sensor-fdc492775544 [{'key': 'missed-message-count', 'value': 2}, {'key': 'acceleration-0-x', ' value': -5.6506500244140625}, {'key': 'acceleration-0-y', 'value': 2.1284141540527344}, {'key': 'acceleration-0-z', 'value': 7.968097686767578}, {'key': 'pressure-0', 'value': 992.178955078125}] Done logging measurement to IO. Took 1.1094765150000967 seconds

bridge-dca63202680a-sensor-fdc492775544 [{'key': 'missed-message-count', 'value': 1}, {'key': 'magnetic-0-x', 'valu e': -0.9061675071716309}, {'key': 'magnetic-0-y', 'value': -21.879562377929688}, {'key': 'magnetic-0-z', 'value': -

100.5845947265625}, {'key': 'temperature-0', 'value': 24.0244140625}] Done logging measurement to IO. Took 0.6365861880001376 seconds

bridge-dca63202680a-sensor-fdc492775544 [{'key': 'missed-message-count', 'value': 0}, {'key': 'acceleration-0-x', ' value': -5.626718521118164}, {'key': 'acceleration-0-y', 'value': 2.1152544021606445}, {'key': 'acceleration-0-z', 'value': 7.981258392333984}, {'key': 'pressure-0', 'value': 992.23876953125}] Done logging measurement to IO. Took 0.6315450570000394 seconds

If you open your Adafruit IO Feeds page, you'll see this feed there.

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Let's have a look at how to work with your feed data.

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BroadcastNet on AIO

Adafruit IO Getting Started

If you're new to Adafruit IO, this guide page (https://adafru.it/JA3) has lots of great info and links to check out.

Renaming AIO Feeds

When you head to your Adafruit IO Feeds page, you'll see the Raspberry Pi bridge name and sensor name pairings of any sensor boards you're running. Here, I have two:

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Since these names are derived from the MAC addresses of the devices themselves, they are good unique IDs, but not very friendly looking! Let's change them.

First, look at the CLUE screen and make note of the sensor ID. In my case it reports caa19e07860b .

Then, click on the feed group of the same name. You'll see a settings gear icon in the Group Info box. Click that.

In the Edit Group popup, give the Name field a more descriptive name. Be sure to leave the Key value as it is or things will break!

Repeat this process for any other boards you're using.

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Dashboard Setup

Set up a new dashboard -- I named mine BroadcastNet Dashboard.

Hit Create to make the new dashboard, which we can then fill with feed data blocks.

Blocks

Now we'll add feed data blocks to the Dashboard.

Press the + icon to add new blocks.

Here I've added a graph widget with the two temperatures from the two different boards.

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You can continue to add elements to the dashboard depending on what you'd like to see!

Measurement List

The BroadcastNet library has many different measurements it can read with the measurement command. You can check out the documentation here (https://adafru.it/JA4).

For convenience, this is the full list:

TVOC

Total Volatile Organic Compounds as a float in parts per billion.

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acceleration

Acceleration as (x, y, z) tuple of floats in meters per second per second.

battery_voltage

Battery voltage in millivolts. Saves two bytes over voltage and is more readable in bare packets.

color

Color as RGB integer.

current

Current as a float in milliamps.

distance

Distance as a float in centimeters.

duty_cycle

16-bit PWM duty cycle. Independent of frequency.

eCO2

Equivalent CO2 as a float in parts per million.

frequency

As integer Hertz

gyro

Gyro motion as (x, y, z) tuple of floats in radians per second.

light

Brightness as a float without units.

lux

Brightness as a float in SI lux.

magnetic

Magnetism as (x, y, z) tuple of floats in micro-Tesla.

orientation

Absolution orientation as (x, y, z) tuple of floats in degrees.

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pressure

Pressure as a float in hectopascals.

relative_humidity

Relative humidity as a float percentage.

temperature

Temperature as a float in degrees centigrade.

value

16-bit unit-less value. Used for analog values and for booleans.

voltage

Voltage as a float in Volts.

weight

Weight as a float in grams.

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Adafruit Bluetooth LE Sensor Nodes User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual