First of all, to manage to glean information from Twitter by avoiding any authentification process pertaining to the Twitter API, I chose to use a content delivery network (CDN) - cdn.syndication.twimg - to obtain the number of followers of a selected Twitter account by its screen name. When I managed to get information from Twitter, I programmed a web application in PHP, named Twitter Follower Tracker, running on Raspberry Pi to print a data packet containing:

Then, I used an Arduino Nano 33 IoT to get my Twitter account information and follower count transferred by the PHP web application and display them with a Nokia 5110 Screen.

Finally, I added a COM-09032 analog joystick and two buttons to control the menu options and scroll text.

After completing wiring on a breadboard and testing the code, I designed a PCB (Twitter Follower Tracker) having the Twitter logo carved at its center. It became a stylish and fitting addition to my desk as an efficient apparatus to track the follower count of my account :)

In addition to displaying information, the device:

Huge thanks to PCBWay for sponsoring this project.

Step 1: Designing and soldering the Twitter Follower Tracker PCB

Before prototyping my PCB design, I tested all connections and wiring with the Arduino Nano 33 IoT on the breadboard.

Then, I designed the Twitter Follower Tracker and Status Notifier PCB by using KiCad. I attached the Gerber file of the PCB below, so if you want, you can order this PCB from PCBWay to create a stylish and fitting apparatus to display the follower count of a selected account and get notified when there is a change, inspired by the Twitter logo :)

Click here to inspect and order this PCB directly on PCBWay.

First of all, by using a soldering iron, I attached headers (female), COM-09032 analog joystick, buzzer, 5mm common cathode RGB LED, 6x6 pushbuttons, 1K resistors, and the power jack.

Component list on the PCB:

A1 (Headers for Arduino Nano 33 IoT)

S1 (Headers for Nokia 5110 Screen)

U1 (COM-09032 Analog Joystick)

BZ1 (Buzzer)

D1 (5mm Common Cathode RGB LED)

K1, K2 (6x6 Pushbutton)

R1, R2, R3, R4, R5 (1K Resistor)

J1 (Power Jack)

Step 2: Setting up a LAMP web server on Raspberry Pi

If you are a novice in programming with Raspberry Pi, you can inspect well-explained instructions and tutorials on the official Raspberry Pi website.

To go to the official Raspberry Pi setting up tutorial, click here.

project-image

⭐ Open a terminal window by selecting Accessories > Terminal from the menu.

⭐ Install the apache2 package by typing the following command into the terminal and pressing Enter:

sudo apt-get install apache2 -y

⭐ To test the server, open Chromium by selecting Internet > Chromium Web Browser from the menu and enter http://localhost.

⭐ If you want, you can use the IP address of your Raspberry Pi as well.

hostname -I

⭐ Install the PHP package with the following command:

⭐ Do not forget to update the Pi.

sudo apt-get update

sudo apt-get install php -y

⭐ To be able to obtain information from the cdn.syndication.twimg (CDN), install the php-curl package:

sudo apt-get install php-curl

⭐ Then, restart the apache server to be able to use the installed packages on the localhost:

sudo service apache2 restart

Step 3: Developing the Twitter Follower Tracker web application in PHP to elicit information from the CDN

Although Twitter provides an API to collate information on Twitter accounts, tweets, replies, etc., I decided to use a content delivery network (CDN) in this project since the Twitter API requires an authentification process and key.

CDN: cdn.syndication.twimg

⭐ CDN uses screen names of Twitter accounts to collect and return this information in JSON:

https://cdn.syndication.twimg.com/widgets/followbutton/info.json?screen_names=

The web application consists of one file - index.php. You can download the web application below to install it on your Raspberry Pi - Twitter_Follower_Tracker.zip.

💻 index.php

⭐ Define the twitter_follower_tracker class and its functions.

⭐ In the __init__ function, define the screen name of the Twitter account, such as ThAmplituhedron.

⭐ In the get_followers function, print information of the given Twitter account.

⭐ Syntax:

#/em>

#/em>

⭐ Define the twitter class object.

// Define the twitter_follower_tracker class and its functions:class twitter_follower_tracker{    public $account;        public function __init__($account){        $this->account = $account;    }        public function get_followers(){        $url = "https://cdn.syndication.twimg.com/widgets/followbutton/info.json?screen_names=".$this->account;        $data = json_decode(file_get_contents($url, true));        echo "%".$data[0]->followers_count."%".$data[0]->name."%".$data[0]->id."%";    }}// Define the new 'twitter' class object:$twitter = new twitter_follower_tracker();$twitter->__init__("ThAmplituhedron");// Print information that of the given Twitter account.$twitter->get_followers();

Step 3.1: Setting up the web application on Raspberry Pi

⭐ First of all, extract the Twitter_Follower_Tracker.zip folder and move the application folder (Twitter_Follower_Tracker) to the apache server (/var/www/html) by using the terminal since the apache server is a protected location.

sudo mv /home/pi/Downloads/Twitter_Follower_Tracker /var/www/html/

⭐ Go to the web application:

http://localhost/Twitter_Follower_Tracker/

Step 4: Setting up the Arduino Nano 33 IoT

If you are a novice in programming with the Arduino Nano 33 IoT, follow the steps below to program it with the Arduino IDE.

⭐ Download the required drivers - Arduino SAMD Core - as explained here

⭐ To be able to connect to the WiFi, download the WiFiNINA library from here.

Step 5: Programming the Arduino Nano 33 IoT

Download the required libraries to be able to control the modules:

Nokia 5110 Screen | Library

⭐ Include required libraries and define the WiFi settings.

// Include required libraries:#include <SPI.h>#include <WiFiNINA.h>#include <LCD5110_Graph.h>char ssid[] = "<SSID>";        // your network SSID (name)char pass[] = "<PASSWORD>";    // your network password (use for WPA, or use as key for WEP)int keyIndex = 0;              // your network key Index number (needed only for WEP)int status = WL_IDLE_STATUS;// Enter the IPAddress of your Raspberry Pi.IPAddress server(192, 168, 1, 20);// Initialize the Ethernet client libraryWiFiClient client; /* WiFiSSLClient client; */

⭐ Define the Nokia 5110 screen settings and the graphics (monochrome images).

⭐ To create different graphics (monochrome images), go to Monochrome Image Converter.

// Define screen settings.LCD5110 myGLCD(2,3,4,5,6);extern uint8_t SmallFont[];extern uint8_t MediumNumbers[];// Define the graphics:extern uint8_t twitter[];

⭐ Initiate the screen and check for the WiFi module to verify the connection.

// Initiate screen.  myGLCD.InitLCD();  myGLCD.setFont(SmallFont);  // Check for the WiFi module:  if (WiFi.status() == WL_NO_MODULE) { myGLCD.print("Connection Failed!", 0, 8); myGLCD.update(); while (true); }  // Attempt to connect to the WiFi network:  while (status != WL_CONNECTED) {    myGLCD.print("Waiting...", 0, 8);    myGLCD.print("Attempting to", 0, 16);    myGLCD.print("connect to", 0, 24);    myGLCD.print("WiFi !!!", 0, 32);    myGLCD.update();    // Connect to WPA/WPA2 network. Change this line if using open or WEP network:    status = WiFi.begin(ssid, pass);    // Wait 10 seconds for connection:    delay(10000);  }

⭐ In the read_controls function, read joystick and control button values.

void read_controls(){  // Joystick:  joystick_x = analogRead(VRX);  joystick_y = analogRead(VRY);  joystick_sw = digitalRead(SW);  // Buttons:  _right = digitalRead(right);  _left = digitalRead(left);}

⭐ In the change_menu_options function:

⭐ Increase or decrease the menu option number (selected) using the Y-axis of the analog joystick.

⭐ Depending on the menu option number (selected), change the boolean status.

void change_menu_options(){  // Increase or decrease the option number using the joystick (VRY).  if(joystick_y >= 900) selected--;   if(joystick_y <= 45) selected++;   if(selected < 0) selected = 4;  if(selected > 4) selected = 1;  delay(100);  // Depending on the selected option number, change the boolean status.  switch(selected){    case 1:      followers = true;      entries = false;      graphics = false;      _sleep = false;    break;    case 2:           followers = false;      entries = true;      graphics = false;      _sleep = false;    break;    case 3:      followers = false;      entries = false;      graphics = true;      _sleep = false;    break;    case 4:      followers = false;      entries = false;      graphics = false;      _sleep = true;    break;  }}

⭐ After being selected, if the followers menu option is activated by pressing the joystick button (SW):

⭐ Get the Twitter account information from the REST API (CDN).

⭐ Check the current follower status using registered status variables:

⭐ If there is an increase or decrease in the follower count, notify the user.

⭐ Update the last entries (follower counts) list.

⭐ Print the Twitter account information and status.

⭐ Scroll the fetched information by using the X-axis of the analog joystick.

⭐ If the Left button is pressed, halt notification (buzzer).

⭐ If the Right button is pressed, return to the interface.

if(followers == true){    do{      myGLCD.invertText(true);      myGLCD.print("A. Followers", 0, 16);      myGLCD.invertText(false);      myGLCD.update();      adjustColor(255, 0, 255);      delay(100);      if(joystick_sw == false){        myGLCD.clrScr();        myGLCD.update();        activated = true;        // Get the Twitter Account Information from the REST API (CDN):        make_a_get_request("/Twitter_Follower_Tracker/");        // Check the follower status using registered status variables:        int _followers = follower_count.toInt();        if(_followers != previous_count){          // If there is an increase or decrease in the follower number, notify the user:          if(_followers > previous_count){ _status = "INC"; adjustColor(0, 255, 0); tone(buzzer, 500); }          if(_followers < previous_count){ _status = "DEC"; adjustColor(255, 0, 0); tone(buzzer, 500); }          // Change the last entries list:          previous_count = _followers;          entry_3 = entry_2;          entry_2 = entry_1;          entry_1 = _followers;        }else{          _status = "STABLE";          adjustColor(0, 0, 255);        }        myGLCD.clrScr();        myGLCD.update();        while(activated == true){          read_controls();          myGLCD.print("Status: " + _status, 0, 0);          myGLCD.print(follower_count, CENTER, 16);          scrolling_text(" Name: " + account_name + " ", 32);          scrolling_text(" ID:" + account_id + " ", 40);          // Halt notification.          if(_left == false) noTone(buzzer);          // Exit.          if(_right == false){ activated = false; x = 0; myGLCD.clrScr(); myGLCD.update(); noTone(buzzer); }                 }      }    }while(followers == false);  }

⭐ After being selected, if the entries menu option is activated by pressing the joystick button (SW):

⭐ Print the registered entries list - last three follower counts.

⭐ If the Left button is pressed, reset the entries list.

⭐ If the Right button is pressed, return to the interface.

if(entries == true){    do{      myGLCD.invertText(true);      myGLCD.print("B. Entries", 0, 24);      myGLCD.invertText(false);      myGLCD.update();      adjustColor(0, 255, 255);      delay(100);      if(joystick_sw == false){        myGLCD.clrScr();        myGLCD.update();        activated = true;        while(activated == true){          read_controls();          // Print the entries list:          myGLCD.print("Entries: ", 0, 0);          myGLCD.print("1 => : " + String(entry_1), 0, 16);          myGLCD.print("2 => : " + String(entry_2), 0, 24);          myGLCD.print("3 => : " + String(entry_3), 0, 32);          myGLCD.update();          // RESET THE ENTRIES LIST:          if(_left == false){ entry_1 = 0; entry_2 = 0; entry_3 = 0; myGLCD.clrScr(); myGLCD.update(); }          // Exit.          if(_right == false){ activated = false; myGLCD.clrScr(); myGLCD.update(); }                 }      }    }while(entries == false);  }

⭐ After being selected, if the graphics menu option is activated by pressing the joystick button (SW):

⭐ Display the monochrome image (twitter) as the screensaver.

⭐ If the Right button is pressed, return to the interface.

if(graphics == true){    do{      myGLCD.invertText(true);      myGLCD.print("C. Graphics", 0, 32);      myGLCD.invertText(false);      myGLCD.update();      adjustColor(255, 255, 0);      delay(100);      if(joystick_sw == false){        myGLCD.clrScr();        myGLCD.update();        activated = true;        while(activated == true){          read_controls();          // Define and print monochrome images:          myGLCD.drawBitmap(20,0,twitter,45,45);          myGLCD.update();          // Exit.          if(_right == false){ activated = false; myGLCD.clrScr(); myGLCD.update(); }         }      }    }while(graphics == false);  }

⭐ After being selected, if the sleep menu option is activated by pressing the joystick button (SW):

⭐ Activate the sleep mode in 10 seconds.

⭐ Print the remaining seconds.

⭐ Display the color pattern while sleeping - red, green, blue, purple, white.

⭐ If the Right button is pressed, return to the interface.

if(_sleep == true){   do{     myGLCD.invertText(true);     myGLCD.print("D. Sleep", 0, 40);     myGLCD.invertText(false);     myGLCD.update();     adjustColor(255, 69, 0);     delay(100);     if(joystick_sw == false){       // Activate the sleep mode in 10 seconds.       myGLCD.clrScr();       myGLCD.print("Entering", CENTER, 0);       myGLCD.print("Sleep Mode", CENTER, 8);       myGLCD.print("in", CENTER, 16);       myGLCD.print("Seconds", CENTER, 40);       myGLCD.update();       // Print remaining seconds.       myGLCD.setFont(MediumNumbers);       for (int s=10; s>=0; s--){ myGLCD.printNumI(s, CENTER, 24, 2, '0'); myGLCD.update(); delay(1000); }       myGLCD.enableSleep();       activated = true;       while(activated == true){         // Color Pattern:         adjustColor(255,0,0);         delay(500);         adjustColor(0,255,0);         delay(500);         adjustColor(0,0,255);         delay(500);         adjustColor(255,0,255);         delay(500);         adjustColor(255,255,255);         delay(500);         // Exit.         read_controls();         if(_right == false){ activated = false; myGLCD.clrScr(); myGLCD.disableSleep(); myGLCD.setFont(SmallFont); adjustColor(0,0,0); }       }     }   }while(_sleep == false); }

Step 5.1: Getting information from the web application and using the analog joystick to scroll text

⭐ In the make_a_get_request function:

⭐ Connect to the web application named Twitter Follower Tracker.

⭐ If the connection is successful, make a Get request to obtain the Twitter account information:

⭐ If there are incoming bytes available, get the response from the web application.

⭐ Split the response string by the predefined delimiter (%) to glean information as substrings - follower_count, account_name, and account_id.

void make_a_get_request(String application){  // Connect to the web application named Twitter_Follower_Tracker. Change '80' with '443' if you are using SSL connection.  if(client.connect(server, 80)){    // If successful:    myGLCD.print("Connected to", 0, 8);    myGLCD.print("the server!!!", 0, 16);    myGLCD.update();    // Make an HTTP Get request:    client.println("GET " + application + " HTTP/1.1");    client.println("Host: 192.168.1.20");    client.println("Connection: close");    client.println();  }else{    myGLCD.print("Connection", 0, 8);    myGLCD.print("Error!!!", 0, 16);    myGLCD.update();  }  delay(2000); // Wait 2 seconds after connection...  // If there are incoming bytes available, get the response from the web application.  String response = "";  while (client.available()) { char c = client.read(); response += c; }  if(response != "" && response.endsWith("%")){    // Split the response string by a pre-defined delimiter in a simple way. '%'(percentage) is defined as the delimiter in this project.    int delimiter_1, delimiter_2, delimiter_3, delimiter_4;    delimiter_1 = response.indexOf("%");    delimiter_2 = response.indexOf("%", delimiter_1 + 1);    delimiter_3 = response.indexOf("%", delimiter_2 + 1);    delimiter_4 = response.indexOf("%", delimiter_3 + 1);    // Glean information as substrings.    follower_count = response.substring(delimiter_1 + 1, delimiter_2);    account_name = response.substring(delimiter_2 + 1, delimiter_3);    account_id = response.substring(delimiter_3 + 1, delimiter_4);  }}

⭐ In the scrolling_text function:

⭐ Scroll a given string using the X-axis of the analog joystick on a given y coordinate (row).

void scrolling_text(String text, int y){  int len = text.length();  // Scroll text using the joystick (VRX).  if(joystick_x <= 45) x--;  if(joystick_x >= 900) x++;  if(x>84) x = 84;  if(x<=-(len*6)) x = -(len*6);  // Print.  myGLCD.print(text, x, y);  myGLCD.update();  delay(25);}

Connections and Adjustments

// Connections
// Arduino Nano 33 IoT :           
//                                Nokia 5110 Screen
// D2  --------------------------- SCK (Clk)
// D3  --------------------------- MOSI (Din) 
// D4  --------------------------- DC 
// D5  --------------------------- RST
// D6  --------------------------- CS (CE)
//                                JoyStick
// A0  --------------------------- VRY
// A1  --------------------------- VRX
// D9  --------------------------- SW
// 5V  --------------------------- 5V
// GND --------------------------- GND
//                                Button (Right)
// A3  --------------------------- S
//                                Button (Left)
// A2  --------------------------- S
//                                RGB LEB (RCGB)
// D12 --------------------------- R
// D11 --------------------------- G
// D10 --------------------------- B
//                                Buzzer
// D8  --------------------------- +

After completing and uploading the code, I attached all required components to the board via headers - the Arduino Nano 33 IoT and the Nokia 5110 Screen.

Modes and Features

📊🔄 First of all, the device checks for a successful WiFi connection. Then, if connected, it displays the interface (menu).

📊🔄 The device shows four different modes on the interface:

📊🔄 The device allows the user to select a mode (option) on the interface via the analog joystick:

📊🔄 While selecting a mode on the interface with the Y-axis of the analog joystick, the device turns the RGB LED to a different color for each mode:

📊🔄 After activating any modes, the device lets the user return to the interface by pressing the Right button.

📌 A. Followers

📊🔄 The device connects to the web application (Twitter Follower Tracker) to obtain the Twitter account information:

📊🔄 The device checks the current follower status in comparison to the previously registered follower count:

📊🔄 Then, the device displays the current follower status, the current follower count, the account name, and the account ID.

📊🔄 If the current follower status is STABLE, which means no change in the follower count, the device turns the RGB LED to blue.


📊🔄 If the current follower status is INC, which means an increase in the follower count, the device turns the RGB LED to green and notifies the user via the buzzer.

📊🔄 If the current follower status is DEC, which means a decrease in the follower count, the device turns the RGB LED to red and notifies the user via the buzzer.

📊🔄 If the Left button is pressed, the device halts the buzzer (notification) and keeps displaying the account information.

📊🔄 The device allows the user to scroll the fetched account information with the X-axis of the analog joystick.

📌 B. Entries

📊🔄 The device displays the last three registered follower counts (entries) chronologically.

📊🔄 If the Left button is pressed, the device resets the entries (follower counts) list.

📌 C. Graphics

📊🔄 The device shows the Twitter logo (monochrome image) as the screensaver.

📌 D. Sleep

📊🔄 The device activates the sleep mode in 10 seconds while printing the remaining seconds.

📊🔄 The device displays the color pattern - red, green, blue, purple, white - during the sleep mode.

Videos and Conclusion

After completing all steps above, I placed the device on my desk by utilizing a plastic easel as a fitting and stylish decoration for my room. It works stupendously :)