Category: BleuIO

Python has a lot of GUI frameworks, but Tkinter is the only framework that’s built into the Python standard library. Tkinter has several strengths. It’s cross-platform, so the same code works on Windows, macOS, and Linux. Visual elements are rendered using native operating system elements, so applications built with Tkinter look like they belong on the platform where they’re run.

Tkinter is lightweight and relatively painless to use compared to other frameworks. This makes it a compelling choice for building GUI applications in Python, especially for applications where a modern sheen is unnecessary, and the top priority is to quickly build something functional and cross-platform.

In this article, we will try to create a simple Python GUI application that can scan for nearby Bluetooth devices using Pyserial and shows the list on the screen.

Requirments 

• Bluetooth Low Energy USB dongle BleuIO (https://www.bleuio.com)
• Pyserial.

Instructions

• Connect the BleuIO to your computer. The script uses pyserial to connect to the Bluetooth USB dongle BleuIO.
• Update the script and write the correct COM port (line 25), where the dongle is connected. 
• After connecting to the dongle, we put the dongle into the central role using AT+CENTRAL so that it can scan for nearby Bluetooth devices. 
• Then we do a simple Gap scan using AT+GAPSCAN=3 command to scan for nearby Bluetooth devices for 3 seconds.
• After that, we read the output from the serial port and filter the device to get the unique number of devices.
• Then we add a timestamp when the scan was completed. 
• Finally, we sort the result by RSSI value before printing it out on screen.
• ‘Scan again’ button will do the whole process again.

Here is the final script file. 

# Gjort av William 
# 2022-06-16 
# Smart Sensors Devices AB
# 
# libraries that is necessary for tkinter to work
import tkinter as tk
from tkinter import  ttk

# this is imported for the dongle and also for the "time.sleep()" commands
import serial
import time

# this is the library that is uesd to check the current time 
import datetime
now = datetime.datetime.now()

# this is what creates the main window
main_window = tk.Tk()

#changes the titel of the window
main_window.title('Scan for nearby Bluetooth devices')


# sets your port for the dongle
your_com_port = "COM18"  
connecting_to_dongle = True

#changes the size of the screens window
window_width = 900
window_height = 500

# get the screen dimension
screen_width = main_window.winfo_screenwidth()
screen_height = main_window.winfo_screenheight()
# find the center point
center_x = int(screen_width/2 - window_width / 2)
center_y = int(screen_height/2 - window_height / 2)
# set the position of the window to the center of the screen
main_window.geometry(f'{window_width}x{window_height}+{center_x}+{center_y}')

# apply the grid layout
main_window.grid_columnconfigure(1, weight=1)
main_window.grid_rowconfigure(1, weight=1)


# create the text widget
text = tk.Text(main_window, height=30, width=30)
text.grid(row=1, column=1, sticky=tk.EW)


# this is the part of the code that communicates whit the dongle
print("Connecting to dongle...")
while connecting_to_dongle:
    try:
        console = serial.Serial(
            port=your_com_port,
            baudrate=57600,
            parity="N",
            stopbits=1,
            bytesize=8,
            timeout=0,
        )
        if console.is_open.__bool__():
            connecting_to_dongle = False
    except:
        print("Dongle not connected. Please reconnect Dongle.")
        time.sleep(5)
print("Connected to Dongle.")

console.write(str.encode("AT+CENTRAL"))
console.write("\r".encode())
print("Putting dongle in Central role.")
time.sleep(0.1)

console.write(str.encode("AT+GAPSCAN=3"))
console.write("\r".encode())
time.sleep(0.1)
print("Looking for nearby Bluetooth devices ...")
dongle_output2 = console.read(console.in_waiting)
time.sleep(3)
print("Scan Complete!")
filtered = []

for dev in dongle_output2.decode().splitlines():
    if len(dev)>20:
        filtered.append(dev.split(maxsplit=1)[1])

seen = set()
out = []
for elem in filtered:
    prefix = elem.split(' ')[1]
    if prefix not in seen:
        seen.add(prefix)
        out.append(elem)

# sort list 
out.sort(key=lambda x:int(x.split()[3]), reverse=True)

# writes out the amount of bluetooth devices found on the main screen
text.insert('0.5', 'Amount of devices found: ' + str(len(out)) + '\n\n')

# funktion to get the current time
def get_time():
    return now.strftime('%H:%M:%S')

# prints out the time of the scan on the main screen
text.insert('1.0','The time of the scan: ' + str(get_time()) + '\n\n')

# writes out the results on the main screen
for i in range(0,len(out)):
    position = f'{i+5}.{len(out[i])}'
    tempStr = out[i] + "\n"
    text.insert(position,f' {tempStr}')

# is supposed to delet everyting on the list
out.clear()

#the funktion for the scan button
def button_clicked():
    # enables the programe to change the results on the main screen to the new ones after the user presses the scan button
    text['state'] = 'normal'
    # update the current time.
    now = datetime.datetime.now()
    # funktion to get the current time
    def get_time():
        return now.strftime('%H:%M:%S')
    # this simply puts a emty row betwen the results and the rest of the output on kommandotolken
    print()
    # this delets the previous output that is on the main screen
    text.delete('0.0', tk.END)

    # this is the part of the code that communicates whit the dongle 
    console.write(str.encode("AT+GAPSCAN=3"))
    console.write("\r".encode())
    time.sleep(0.1)
    
    dongle_output2 = console.read(console.in_waiting)
    time.sleep(3)
    filtered = []

    for dev in dongle_output2.decode().splitlines():
        if len(dev)>20:
            filtered.append(dev.split(maxsplit=1)[1])

    seen = set()
    out = []
    for elem in filtered:
        prefix = elem.split(' ')[1]
        if prefix not in seen:
            seen.add(prefix)
            out.append(elem)

    # sort list 
    out.sort(key=lambda x:int(x.split()[3]), reverse=True)

    
    #writes out the time of the scan on the main screen
    text.insert('1.0','The time of the scan: ' + str(get_time()) + '\n\n')

     # writes out the amount of bluetooth devices found on the main screen
    text.insert('0.0', 'Amount of devices found: ' + str(len(out)) + '\n\n')

    # writes out the results on the main screen
    for i in range(0,len(out)):
        position = f'{i+5}.{len(out[i])}'
        tempStr = out[i] + "\n" 
        text.insert(position,f' {tempStr}')

    # makes it so that you cant edite the results on the main screen
    text['state'] = 'disabled'

#what calls the function for the scan button. also fixes what the user will see as the buttons name.
main_button = ttk.Button(
    main_window,
    text='Scan again',
    command=lambda: button_clicked()
)
# creat the scan button 
main_button.grid(row=0, column=1, sticky=tk.EW)

# just an exit button.
exit_button = ttk.Button(
    main_window,
    text='Exit',
    command=lambda: main_window.quit()
)
# this determens were the exit button is located 
exit_button.grid(row=2, column=1, sticky=tk.EW)

# makes it so that you cant edite the results on the main screen
text['state'] = 'disabled'

# keeps the main window open
main_window.mainloop()

time.sleep(1)
console.close()

Source code is available at https://github.com/smart-sensor-devices-ab/python_gui_tkinter_bluetooth.git

Run the script

To run the script we use start

pythonw Scan_ble.pyw

Note : Scan_ble.pyw is the file name

Output

After running the script, we see a total 25 devices found nearby. We can scan again using the ‘Scan again’ button

Bluetooth Low Energy (BLE) is a low-power wireless technology used for connecting devices with each other. It is a popular communication method, especially in the era of the Internet of Things. Several devices around the house have a built-in Bluetooth transceiver and most of them provide useful capabilities to automate jobs. For that reason, it is really interesting to create a desktop application using C# that connects to the devices around the house and manages them.

In this example, we are going to create a simple C# windows form application that scans and shows a list of nearby Bluetooth devices. 

Let’s start

As a first step let’s create a new project in visual studio and select C# windows form application from the list.

Choose a suitable name for your project.
Once the project is created, we will see a blank form screen where we will add buttons and labels to communicate with BleuIO graphically through the serial port.

We will have buttons that connect and disconnects from the dongle. We create a button called Scan. And a text area will display a list of Bluetooth devices.
The form will look like this

The .cs file associated to this will have the following code.
Source code is available at https://github.com/smart-sensor-devices-ab/c-sharp-scan-bluetooth-device.git

using System;
using System.IO.Ports;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace Scan_BLE_devices
{
    public partial class Form1 : Form
    {
        SerialPort mySerialPort = new SerialPort("COM18", 57600, Parity.None, 8, StopBits.One);
        public Form1()
        {
            InitializeComponent();
            mySerialPort.DataReceived += new SerialDataReceivedEventHandler(mySerialPort_DataReceived);
            mySerialPort.Open();

        }

        //print response from the dongle
        private void mySerialPort_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            SerialPort sp = (SerialPort)sender;
            string s = sp.ReadExisting();
            output_data.Invoke(new EventHandler(delegate { output_data.Text += s + "\r\n"; }));
            //lbl_output.Invoke(this.myDelegate, new Object[] { s });
        }





   

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void btn_disconnect_Click_1(object sender, EventArgs e)
        {
            mySerialPort.Close();
            Environment.Exit(0);
        }

        private void button1_Click_1(object sender, EventArgs e)
        {
            lbl_test.Text = "Connected";
        }

        private void submit_cmd_Click_1(object sender, EventArgs e)
        {
            output_data.Text = "";
            byte[] bytes = Encoding.UTF8.GetBytes("AT+CENTRAL");
            var inputByte = new byte[] { 13 };
            bytes = bytes.Concat(inputByte).ToArray();
            mySerialPort.Write(bytes, 0, bytes.Length);

            System.Threading.Thread.Sleep(1000);
            output_data.Text = "";
            byte[] bytes2 = Encoding.UTF8.GetBytes("AT+GAPSCAN=3");
            var inputByte2 = new byte[] { 13 };
            bytes2 = bytes2.Concat(inputByte2).ToArray();
            mySerialPort.Write(bytes2, 0, bytes2.Length);
            //System.Threading.Thread.Sleep(3000);
        }

        private void output_data_TextChanged(object sender, EventArgs e)
        {

        }
    }
}

As you can notice I wrote COM18 to connect to serial port because BleuIO device on my computer is connected to COM18.
You can check your COM port from device manager.
Lets run the project and click on connect button.

Once we are connected to BlueIO dongle through serial port, we will be able to scan for nearby Bluetooth device. Clicking on Scan button will show a list of nearby Bluetooth device on the screen.

Output

Bluetooth Advertisements are crucial for any BLE device since they are utilized for all types of applications, whether that’s a device that allows connections or one that simply advertises its presence and includes data for others to discover.

The most important goal of advertising packets is to convey information to other BLE devices via the advertising packet type, and the advertising data types included in the packet.

Bluetooth beacons are the most prominent devices that take full advantage of Bluetooth advertising packets. This is due to the reason that most beacons stay in the advertising state throughout their lifetime (do not allow connections), so they rely completely on advertising for relaying the relevant information to the scanning devices.

I tried to create a simple python example script that scans for nearby Bluetooth devices and returns the manufacturer company information by reading the advertising packet.

Requirments 

• Bluetooth Low Energy USB dongle BleuIO (https://www.bleuio.com)
• Pyserial.

Steps

• Get the script from GitHub at https://github.com/smart-sensor-devices-ab/python_bluetooth_device_info.git
• Connect the BleuIO to your computer. The script uses pyserial to connect to the Bluetooth USB dongle BleuIO.
• Update the script and write the correct COM port, where the dongle is connected. (main.py line 6)
• After connecting to the dongle, we put the dongle into the central role so that it can scan for nearby Bluetooth devices. 
• Then we do a simple Gap scan using AT+GAPSCAN=3 command to scan for nearby Bluetooth devices for 3 seconds.
• After that, we read the output from the serial port and print out the list of devices with MAC addresses.
• User selects a device to get manufacturer company information
• We read the advertising packet for this specific device. 
• Pass the response to a function which separates the manufacturer id. 
• Then we try to find a match from an object which I have downloaded recently from https://www.bluetooth.com/specifications/assigned-numbers/company-identifiers/
• The company name shows on the screen.

Here is the final script file. 

import serial
import time
from companydata import companyData
       

your_com_port = "COM18"  # Change this to the com port your dongle is connected to.
connecting_to_dongle = True

print("Connecting to dongle...")
# Trying to connect to dongle until connected. Make sure the port and baudrate is the same as your dongle.
# You can check in the device manager to see what port then right-click and choose properties then the Port Settings
# tab to see the other settings

# function to get company name from advertised id
def getCompany(adv):
  # example advertised package would look like this 
  # 0201061BFF5B070504220118A3003127ED006901090100000000000001BD03
  # explains here 
  # https://twitter.com/josryke/status/763006284052463617/photo/1
  indentifierReversed=''
  # first part 02 is the length
  length = int(adv[0:2],16)  
  pl =int(adv[length*2+2:length*2+4 ], 16) 
  # this gives us 1B which is 27 in decimal. that is our length
  startsFrom = length*2+4
  # this gives us 8, from where it starts
  # now get the packet
  fd=adv[startsFrom:pl]
  # look for the position of flag FF
  flagPosition = fd.find("FF")
  if flagPosition!=-1:    
    identifier = fd[flagPosition+2:flagPosition+6]
    # get 5B07
    indentifierReversed = identifier[2]+identifier[3]+identifier[0]+identifier[1]
    # get 075B
    # now look for the company name on the list
    for attr in companyData:
        if attr['Hexadecimal']=='0x'+indentifierReversed:
            theName=attr['Company']
  else:
    indentifierReversed='-'
    theName='Unknown'
  
  return theName

while connecting_to_dongle:
    try:
        console = serial.Serial(
            port=your_com_port,
            baudrate=115200,
            parity="N",
            stopbits=1,
            bytesize=8,
            timeout=0,
        )
        if console.is_open.__bool__():
            connecting_to_dongle = False
    except:
        print("Dongle not connected. Please reconnect Dongle.")
        time.sleep(5)

print("Connected to Dongle.")

#put the dongle in dual role, so we can scan for nearby device
console.write(str.encode("AT+CENTRAL"))
console.write("\r".encode())
print("Putting dongle in Central role.")
time.sleep(0.1)
# Scan for nearby devices for 3 seconds
console.write(str.encode("AT+GAPSCAN=3"))
console.write("\r".encode())
time.sleep(0.1)
print("Looking for nearby Bluetooth devices ...")
dongle_output2 = console.read(console.in_waiting)
time.sleep(3)
filtered = []
# Filter out unncecssary outputs and keep only the list of devices (also remove index)
for dev in dongle_output2.decode().splitlines():
    if len(dev)>20:
        filtered.append(dev)

# Get unique device by device id and add distance to each raw        
seen = set()
out = []
for elem in filtered:
    prefix = elem.split(' ')[2]
    if prefix not in seen:
        seen.add(prefix)
        out.append(elem) 

# sort list by closest device
# out.sort(key=lambda x:int(x.split()[3]),reverse=True)
print("Scan Completed! "+ str(len(out)) +" devices found.")
# print(out)
for i in range(0, len(out)):
    print (out[i]) 

getInput = input("Select device from the list to get company identifier information (ex.1): ")
deviceToScan = out[int(getInput)-1].split(" ")[2]
# clear output
console.flushInput()
console.flushOutput()
time.sleep(0.1)
# Scan for advertised data of the selected device for 4 seconds
console.write(str.encode("AT+SCANTARGET="+deviceToScan+"=4"))
console.write("\r".encode())
time.sleep(0.1)
print("Getting company identifier information ...")
dongle_output3 = console.read(console.in_waiting)
time.sleep(5)
resp = dongle_output3.decode().splitlines()
# get the adv data only 
for d in resp:
    if('[ADV]' in d):
        companyName=getCompany(d.split(" ")[-1])
        break;
print(companyName)               
time.sleep(0.1)
console.close()

Output

After running the script, we see a total of 20 devices found nearby. The script prints out the manufacturer company information of the device [05] Device: [1]C1:BF:22:71:81:36

Bluetooth ranging technology is very popular. There are many localization systems that exist based on beacons. Beacon technology usually estimates the distance between devices using the received signal strength (RSSI). 

Bluetooth can be an excellent way to narrow down a search area at close distances when tracking something. This feature can be used in several fields. such as Secure Locks for Buildings and Automotive, Asset localization & tracking, Indoor navigation etc

GPS tracking isn’t excellent at giving accurate measurements of the close distance, especially in the indoor environment. On the other hand, Bluetooth is excellent in short ranges because the waves can go through walls. This might fill the gap that GPS tracking has when tracking devices in indoor spaces.

However, most calculations of the distance between two Bluetooth devices are estimates. It’s hard to determine the exact distance between two Bluetooth devices because many factors affect the calculations. Despite the challenges, there are methods to determine the distance between two Bluetooth devices with an accuracy of at least 80%.

The ranging method is simple to implement, and it has the formula to calculate the distance between two Bluetooth devices. As the name suggests, both devices need to be within Bluetooth range to estimate the distance. 

This article will share a simple python script to determine nearby Bluetooth devices and their distance in meters.

This script scans for nearby Bluetooth devices and gets an approximation of the distance by using the well-known RSSI to distance formula.

Read more about how to calculate the distance

How to Calculate Distance from the RSSI value of the BLE Beacon

Requirments 

• Bluetooth Low Energy USB dongle BleuIO (https://www.bleuio.com)
• Pyserial.

Instructions

• Get the script from GitHub at https://github.com/smart-sensor-devices-ab/python_bluetooth_device_distance_meter.git
• Connect the BleuIO to your computer. The script uses pyserial to connect to the Bluetooth USB dongle BleuIO.
• Update the script and write the correct COM port, where the dongle is connected. 
• After connecting to the dongle, we put the dongle into the central role so that it can scan for nearby Bluetooth devices. 
• Then we do a simple Gap scan using AT+GAPSCAN=3 command to scan for nearby Bluetooth devices for 3 seconds.
• After that, we read the output from the serial port and use our RSSI to distance formula to get the distance in meters. 
• Finally, we sort the result by distance before printing it out on screen.

Here is the final script file. 

import serial
import time

your_com_port = "COM18"  # Change this to the com port your dongle is connected to.
connecting_to_dongle = True

print("Connecting to dongle...")
# Trying to connect to dongle until connected. Make sure the port and baudrate is the same as your dongle.
# You can check in the device manager to see what port then right-click and choose properties then the Port Settings
# tab to see the other settings

while connecting_to_dongle:
    try:
        console = serial.Serial(
            port=your_com_port,
            baudrate=57600,
            parity="N",
            stopbits=1,
            bytesize=8,
            timeout=0,
        )
        if console.is_open.__bool__():
            connecting_to_dongle = False
    except:
        print("Dongle not connected. Please reconnect Dongle.")
        time.sleep(5)

print("Connected to Dongle.")

# function to convert rssi to distance in meter
def rssiToDistance(rssi):    
  n=2
  mp=-69
  return round(10 ** ((mp - (int(rssi)))/(10 * n)),2)    

#put the dongle in dual role, so we can scan for nearby device
console.write(str.encode("AT+CENTRAL"))
console.write("\r".encode())
print("Putting dongle in Central role.")
time.sleep(0.1)
# Scan for nearby devices for 3 seconds
console.write(str.encode("AT+GAPSCAN=3"))
console.write("\r".encode())
time.sleep(0.1)
print("Looking for nearby Bluetooth devices ...")
dongle_output2 = console.read(console.in_waiting)
time.sleep(3)
print("Scan Complete!")
filtered = []
# Filter out unncecssary outputs and keep only the list of devices (also remove index)
for dev in dongle_output2.decode().splitlines():
    if len(dev)>20:
        filtered.append(dev.split(maxsplit=1)[1])
# Get unique device by device id and add distance to each raw        
seen = set()
out = []
for elem in filtered:
    prefix = elem.split(' ')[1]
    if prefix not in seen:
        seen.add(prefix)
        out.append(elem + " Distance: "+str(rssiToDistance(elem.split()[3]))+" meter") 

# sort list by closest device
out.sort(key=lambda x:int(x.split()[3]),reverse=True)

# print(out)
for i in range(0, len(out)):
    print (out[i]) 

time.sleep(0.1)
console.close()

Output

After running the script, we see a total 20 devices found nearby. The list shows their distance in meter from the central device.

There are so many Bluetooth-enabled smart devices that it can be confusing how the technology connects the devices. Often we want to connect to multiple peripheral devices simultaneously to get advertised packets or do other operations. In this article, we will see how we can get advertised packets from two different Air quality monitoring sensor devices. 

For this project, we will use Chrome Web serial API to connect to a Bluetooth USB dongle. Using the serial port read/write operation we will scan for specific device advertised data and filter out what we need. After that, we decode the advertised packet to meaningful air quality data using the device documentation.

Requirments

1. BleuIO Bluetooth USB dongle x1
2. HibouAir Air quality monitor x2

Steps

At first, we will get the bleuIO javascript library from NPM. This library will help us easily connect to the serial port,wtire AT commands and read responses in real-time.

Type npm i bleuio on the command prompt of your project root folder.

After that, we create two files. index.html and script.js

Index.html will be responsible for the output and layouts of the project. 

Script.js will have the programming and logic to connect to the dongle and read/write data.

There will be two buttons connect and get data.

The connect button will connect to the bleuIO dongle using the serial port. 

The get data button will do several tasks.

At first, we put the dongle in a dual role (central mode) so that it can scan for peripheral devices. Then we will look for advertised data with their sensor ID one after another. 

Using the documentation from the air quality device, we decode the advertised data.

Finally, we print it out on the screen.

Here is the index.html file code

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <title>Bootstrap demo</title>
    <link
      href="https://cdn.jsdelivr.net/npm/bootstrap@5.2.0-beta1/dist/css/bootstrap.min.css"
      rel="stylesheet"
      integrity="sha384-0evHe/X+R7YkIZDRvuzKMRqM+OrBnVFBL6DOitfPri4tjfHxaWutUpFmBp4vmVor"
      crossorigin="anonymous"
    />
  </head>
  <body>
    <div class="container mt-5">
      <h1>Get air quality Bluetooth LE sensor data from multiple devices</h1>
      <br /><br /><br /><button
        id="connect"
        class="btn btn-success btn-lg me-5"
      >
        Connect
      </button>
      <button id="getData" class="btn btn-warning btn-lg ms-5">Get Data</button>
      <br />
      <br />
      <div id="loading" style="display: none">Fetching Data ...</div>
      <br />
      <div id="airData"></div>
    </div>

    <script src="script.js"></script>
  </body>
</html>

Here is script.js file code

import * as my_dongle from 'bleuio'
document.getElementById('connect').addEventListener('click', function(){
  my_dongle.at_connect()
  document.getElementById("connect").classList.add('disabled');
})
let dev1BoardID='45840D'
let dev2BoardID='60FDED'
document.getElementById('getData').addEventListener('click', function(){
    
    //show loading
    document.getElementById("loading").style.display = "block";
    //make the dongle in dual role , so it can scan for peripheral devices advertised data
    my_dongle.at_dual().then(()=>{
        //scan for a devices advertised data, a PM sensor
        my_dongle.at_findscandata(dev1BoardID,8).then((x)=>{
            //it returns an array of advertised data
            //from the array, we take the last one
            //it looks like this "[F9:0D:35:E7:72:65] Device Data [ADV]: 0201061BFF5B07050345840DB1031527FB002A010402040004000400000001"
            //then we split it by space
            //so we can get the advertised data only (the last part)
            return x[x.length-1].split(" ").pop()
        }).then((adv1)=>{ 
            //now lets decode the advertised data for this device using the device documentaion
            let pmEnvData=advDataDecode(adv1)
            //we do the same process to get advertised data of another device
            //after waiting 1 seconds
            setTimeout(()=>{
                my_dongle.at_findscandata(dev2BoardID,8).then((y)=>{
                    let adv2= y[y.length-1].split(" ").pop()
                    //again we decode the advertised data for this device using the device documentaion
                    let co2EnvData=advDataDecode(adv2)
                    //now merge pm data to this array
                    co2EnvData.pm1=pmEnvData.pm1
                    co2EnvData.pm25=pmEnvData.pm25
                    co2EnvData.pm10=pmEnvData.pm10
                    document.getElementById('airData').innerHTML=`
                    Air Quality data from PM and CO2 sensor devices<br/><br/>
                    CO2 : ${co2EnvData.co2} ppm<br/>
                    PM 1.0 : ${co2EnvData.pm1} µg/m³<br/>
                    PM 2.5 : ${co2EnvData.pm25} µg/m³<br/>
                    PM 10 : ${co2EnvData.pm10} µg/m³<br/>
                    Temperature : ${co2EnvData.temp} °C<br/>
                    Humidity : ${co2EnvData.hum} %rH<br/>
                    Pressure : ${co2EnvData.pressure} mbar<br/>
                    Light : ${co2EnvData.light} Lux<br/>

                    `
                    //hide loading
                    document.getElementById("loading").style.display = "none"; 
                })
            },1000)
            
        })
    })
    

  })

  const advDataDecode =((data)=>{
    let pos = data.indexOf("5B0705")
    let dt = new Date();
    let currentTs = dt.getFullYear() 
    + '/' 
    + (dt.getMonth() + 1).toString().padStart(2, "0") 
    + '/' 
    + dt.getDate().toString().padStart(2, "0")
    +' '
    +
    dt.getHours().toString().padStart(2, "0")
    +
    ':'
    +
    dt.getMinutes().toString().padStart(2, "0")
    +
    ':'
    +dt.getSeconds().toString().padStart(2, "0")
    let tempHex=parseInt('0x'+data.substr(pos+22,4).match(/../g).reverse().join(''))
    if(tempHex>1000)
        tempHex = (tempHex - (65535 + 1) )/10
    else
        tempHex = tempHex/10
    return {
      "boardID":data.substr(pos+8,6),
      "type":data.substr(pos+6,2),
      "light":parseInt('0x'+data.substr(pos+14,4).match(/../g).reverse().join('')),
      "pressure":parseInt('0x'+data.substr(pos+18,4).match(/../g).reverse().join(''))/10,
      "temp":tempHex,
      "hum":parseInt('0x'+data.substr(pos+26,4).match(/../g).reverse().join(''))/10,
      "pm1":parseInt('0x'+data.substr(pos+34,4).match(/../g).reverse().join(''))/10,
      "pm25":parseInt('0x'+data.substr(pos+38,4).match(/../g).reverse().join(''))/10,
      "pm10":parseInt('0x'+data.substr(pos+42,4).match(/../g).reverse().join(''))/10,
      "co2":parseInt('0x'+data.substr(pos+46,4)),
      "ts":currentTs
    }
})

Source code also available on github

https://github.com/shuhad/bluetooth_mutiple_device_read

Run the script

You can either clone the script from github or follow the instructions and make a new project.

For this project to run we may need a web build tool. I prefer using parcel.

https://parceljs.org/

install parcel if you don’t have

npm install --save-dev parcel

Now run the script using

parcel index.html

Output

The script can be modified to read more than two devices as required.

Home automation involves automating household environment equipment. To achieve that, we have created a smart bulb that can be controlled remotely using smart phone app. The aim of this project is to control different home appliances using smartphone at your home.

Introduction

This example is showing how to control a GPIO pin on a RaspberryPi remotely from a smart phone (or another BleuIO Dongle).

For this example we will need:

• A RaspberryPi
• A BleuIO Dongle (https://www.bleuio.com/)
• Our example python script (https://github.com/smart-sensor-devices-ab/bleuio_rpi_switch_example)
• A way to connect to the GPIO Pin (Like a 5V Relay and a Lightbulb)

WARNING – THIS PROJECT INVOLVES HIGH VOLTAGES THAT CAN CAUSE SERIOUS INJURY OR DEATH. PLEASE TAKE ALL NECESSARY PRECAUTIONS, AND TURN OFF ALL POWER TO A CIRCUIT BEFORE WORKING ON IT.

Connecting the relay

Beware:

Always be very careful when experimenting with AC, electrical shock can result in serious injuries! NOTICE OF RISK; DISCLAIMER OF LIABILITY

Instructions for bleuio_rpi_switch_example.py

• Connect the BleuIO Dongle to your RaspberryPi.
• Edit the variable ‘switch’ in the script to the GPIO pin you want to use. (You can use the command pinout to get a graphical view showing you the GPIO pins for the board)

• Finally just run python script and and use your phone to connect to the BleuIO Dongle and send on/off messages to controll the GPIO!

Instructions for connecting to the BleuIO from mobile

• Download a BLE scanning App that can connect and read/write to a device. (Like nRFConnect or BLEScanner)
  Android, IOS

• Look for the dongle, it will be advertising as ‘BleuIO’.

• Connect to the BleuIO Dongle.

• To enable BleuIO to recieve commands you must first write 0x01 to the Flow Control characteristic (UUID: 0783b03e-8535-b5a0-7140-a304d2495cb9)

• Now you can write to the Server RX Data characteristic (UUID: 0783b03e-8535-b5a0-7140-a304d2495cba) to control the GPIO.
  |CMD|Effect|
  |–|–|
  |“SW=1”| ON|
  |“SW=0”| OFF|

The script

Here is the python script that receives the messages from smart phone app and helps control the light.

#!/usr/bin/python3
# Copyright 2022 Smart Sensor Devices in Sweden AB
#
# 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.

import time
import serial.tools.list_ports
import serial
import RPi.GPIO as io


switch = 7  # Edit this to suit your setup! (7 = GPIO 04), use command pinout to graphically show you the GPIO pins for the board
io.setmode(io.BOARD)
io.setup(switch, io.OUT)

master_array = []
index = 1
dongle_port = ""

print("\nWelcome to BleuIO RaspberryPi Switch Example!\n")

print("\nPlease insert dongle...")
try:
    while len(master_array) == 0:
        m_ports = serial.tools.list_ports.comports(include_links=False)
        for port in m_ports:
            if str(port.hwid).__contains__("VID:PID=2DCF"):
                master = port.device + " " + port.hwid
                if master.__contains__("VID:PID=2DCF:6002"):
                    print("Found dongle in port: %s" % port.device)
                    master_array.append(master)
                    dongle_port = port
                    break

    for dongle in master_array:
        print("\nConnecting to BleuIO @ %s\n" % dongle)

    time.sleep(0.5)
    dongle_conn = serial.Serial(
        dongle_port.device,
        115200,
        timeout=1,
    )

    if not dongle_conn.is_open:
        dongle_conn.open()

    print("Starting Advertising...")
    dongle_conn.write("AT+GAPDISCONNECTALL\rAT+DUAL\rAT+ADVSTART\rATI\r".encode())
    read_tries = 0
    dongle_resp = ""
    while read_tries < 20:
        dongle_resp = dongle_conn.readline().decode()
        if "Not Advertising" in dongle_resp:
            dongle_conn.write("AT+ADVSTART\r")
        if b"Advertising\r\n" in dongle_resp.encode():
            break
        read_tries += 1
        time.sleep(0.01)

    if dongle_resp:
        print("BleuIO is %s" % dongle_resp)
    else:
        print("ERROR! No response...")
        exit()

    print(
        "Going into loop, waiting for signal to turn switch on/off...\n(Press Ctrl+C to abort)"
    )
    while True:
        try:
            dongle_resp = dongle_conn.readline().decode()
            if "SW=0" in dongle_resp:
                print("Turn Switch off!")
                io.output(switch, io.LOW)
            if "SW=1" in dongle_resp:
                print("Turn Switch on!")
                io.output(switch, io.HIGH)
        except KeyboardInterrupt:
            if dongle_conn.is_open:
                dongle_conn.write("AT+GAPDISCONNECTALL\rAT+ADVSTOP\r".encode())
                dongle_conn.close()
                io.cleanup()
            print("\nBye!")
            exit()

except Exception as e:
    print("(ERROR: %s)" % (e))

Output

We have tested the script using nRFConnect app from both IOS and Android phone to turn on/off the light bulb. Here is the output of this project.