Nokia 5110 LCD Display Demo with Xiao RP2040

Exploring retro display capabilities with modern microcontroller

What I Built

I created a demonstration of the Nokia 5110 LCD display (84x48 pixels) using my Xiao RP2040 board. The demo shows text centering, display rotation, and contrast adjustment capabilities.

Display rotation

Text centering

Contrast control

Parts I Used

Seeed Studio Xiao RP2040

Compact but powerful microcontroller

Nokia 5110 LCD

84×48 pixel monochrome display

Jumper wires

For making connections

Libraries I Installed

I installed the following libraries through the Arduino Library Manager:

Open Arduino IDE and go to Sketch > Include Library > Manage Libraries...
Search for and install Adafruit GFX Library
Search for and install Adafruit PCD8544 Nokia 5110 LCD library
The SPI library comes with the Arduino IDE by default

How I Connected Everything

I wired the Nokia 5110 to my Xiao RP2040 like this:

Nokia 5110 Pin	Xiao RP2040 Connection
CLK (SCK)	D8
DIN (MOSI)	D10
DC (Data/Command)	D3
CE (Chip Enable)	D2
RST (Reset)	D0
VCC	3.3V
GND	GND

How My Project Works

The Nokia 5110 LCD is controlled using SPI communication. My demo shows several key features:

Custom text centering function that automatically positions text
Display rotation through all four orientations (0°, 90°, 180°, 270°)
Contrast adjustment demonstration from 10 to 65
Basic graphics drawing (rectangles and circles)

My Code

Here's the Arduino code I used:

#include <SPI.h>
        #include <Adafruit_GFX.h>
        #include <Adafruit_PCD8544.h>
        
        #define LCD_CLK   D8  // SCK
        #define LCD_DIN   D10  // MOSI
        #define LCD_DC    D3  // Data/Command
        #define LCD_CE    D2  // Chip Enable
        #define LCD_RST   D0  // Reset
        
        Adafruit_PCD8544 display = Adafruit_PCD8544(LCD_CLK, LCD_DIN, LCD_DC, LCD_CE, LCD_RST);
        
        // Custom function to center text
        void centerText(const char *text, uint8_t textSize = 1, int16_t yOffset = 0) {
          display.setTextSize(textSize);
          display.setTextColor(BLACK);
         
          int16_t x, y;
          uint16_t w, h;
          display.getTextBounds(text, 0, 0, &x, &y, &w, &h);
         
          display.setCursor((display.width() - w) / 2, (display.height() - h) / 2 + yOffset);
          display.print(text);
        }
        
        void setup() {
          Serial.begin(115200);
          Serial.println("Nokia 5110 LCD Demo");
          // Initialize display
          display.begin();
          display.setContrast(60);  // Adjust contrast (0-127)
          display.setRotation(2);   // 180° rotation
          display.clearDisplay();
          // Display startup message
          centerText("Manzi Armel Test", 1, -10);
          centerText("Rotated 180°", 1, 0);
          centerText("Fablab", 1, 10);
          display.display();
          delay(2000);
        }
        
        void loop() {
          // Animation sequence
          for (int i = 0; i < 4; i++) {
            display.clearDisplay();
            display.setRotation(i);  // Cycle through rotations
           
            // Draw a rotating rectangle
            display.drawRect(10, 10, display.width()-20, display.height()-20, BLACK);
            display.fillCircle(display.width()/2, display.height()/2, 5, BLACK);
           
            // Show current rotation
            centerText("Rotation:", 1, -10);
            centerText(String(i * 90).c_str(), 2, 5);
           
            display.display();
            delay(1500);
          }
        
          // Contrast adjustment demo
          for (int c = 10; c < 70; c += 5) {
            display.clearDisplay();
            display.setContrast(c);
            centerText("Contrast:", 1, -10);
            centerText(String(c).c_str(), 2, 5);
            display.display();
            delay(200);
          }
        }

What Each Part of My Code Does

Library Includes:

SPI.h: Handles SPI communication with the display
Adafruit_GFX.h: Provides graphics functions
Adafruit_PCD8544.h: Nokia 5110-specific driver

In the setup() function:

Initializes serial communication at 115200 baud
Sets up the display with initial contrast (60) and rotation (180°)
Displays a centered startup message using our custom function

In the main loop():

Cycles through all 4 display rotations (0-3)
Draws a rectangle and centered circle for each rotation
Shows the current rotation angle in degrees
Demonstrates contrast adjustment from 10 to 65 in steps of 5

The centerText() function:

Automatically calculates text width and height
Positions text perfectly centered on the display
Accepts optional parameters for text size and vertical offset
Can be reused in other projects for easy text positioning

Video Demonstration

RFID Access Control System with a feedback Nokia LCD

Building an access system with XIAO RP2040 will help me with final project

What I Built

I created access control system that combines RFID authentication with visual feedback. When users scan their RFID cards, the system instantly verifies authorization and displays the result on a classic Nokia 5110 LCD screen.

I used the rfid in the previous input device week09

RFID card reading

Nokia LCD feedback

LED status indicators

Hardware Components

Here's what I gathered from my workbench:

XIAO RP2040

The brains of the operation - small but powerful!

MFRC522 RFID

My security guard - scans cards up close

Nokia 5110 LCD

Retro display with crisp pixels

Wiring It All Up

Connecting everything required some careful pin planning:

Component	XIAO Pin	Note
RFID SDA	D4	Chip select
RFID SCK	D8	Shared clock
LCD RST	D0	Display reset
LCD CE	D2	Chip enable
LED	D1	Status indicator

Issue Face: I experienced an issue where the RFID card reader only works when you comment out or remove certain LCD-related code. This suggests there might be a conflict between the RFID and LCD functionality, likely related to SPI communication or pin usage. Cause D8 CLK and D10 MOSI both device was requesting those port

How i solved it:I changed the connection for the lcd (DIN MOSI pin was connected to D7 and CLK connected to D5) then i let the RFID use the normal D8 for SCK and D10 for MOSI and it worked

Software Setup

Getting the code ready was half the battle:

              #include 
              #include 
              #include 
              #include 
              
              // Pin Configuration
              #define RST_PIN     D6    // RFID Reset
              #define SS_PIN      D4    // RFID Chip Select
              #define LED_PIN     D1    // Status LED
              
              // LCD Pins (using software SPI)
              #define LCD_CLK     D5    // Clock
              #define LCD_DIN     D7    // Data In
              #define LCD_DC      D3    // Data/Command
              #define LCD_CE      D2    // Chip Enable
              #define LCD_RST     D0    // Reset
              
              // System Constants
              const byte authorizedUID[4] = {0xAA, 0xC4, 0x2F, 0x43}; // Replace with your card UID
              const int CONTRAST = 60;  // LCD contrast (0-127)
              const int BLINK_DELAY = 200; // LED blink duration
              
              // Device Objects
              MFRC522 rfid(SS_PIN, RST_PIN);
              Adafruit_PCD8544 display = Adafruit_PCD8544(LCD_CLK, LCD_DIN, LCD_DC, LCD_CE, LCD_RST);
              
              void setup() {
                initializeSerial();
                initializeLED();
                initializeDisplay();
                initializeRFID();
                showStartupScreen();
              }
              
              void loop() {
                indicateSystemActive();
                
                if (isCardPresent()) {
                  handleCardDetection();
                }
                
                delay(100); // Main loop delay
              }
              
              // Initialization Functions
              void initializeSerial() {
                Serial.begin(115200);
                while (!Serial);
                Serial.println("\nStarting Access Control System");
              }
              
              void initializeLED() {
                pinMode(LED_PIN, OUTPUT);
                blinkLED(3, BLINK_DELAY);
              }
              
              void initializeDisplay() {
                display.begin();
                display.setContrast(CONTRAST);
                display.setRotation(0);
                display.clearDisplay();
                display.display();
              }
              
              void initializeRFID() {
                SPI.begin();
                rfid.PCD_Init();
                
                byte version = rfid.PCD_ReadRegister(rfid.VersionReg);
                Serial.print("RFID Version: 0x");
                Serial.println(version, HEX);
                
                if (version == 0x00 || version == 0xFF) {
                  showRFIDError();
                  while (true) blinkLED(1, 100); // Halt on error
                }
              }
              
              // Display Functions
              void showStartupScreen() {
                display.clearDisplay();
                centerText("Access", 1, -10);
                centerText("Control", 1, 0);
                centerText("System", 1, 10);
                display.display();
                delay(2000);
                showReadyScreen();
              }
              
              void showReadyScreen() {
                display.clearDisplay();
                centerText("Ready", 1, -5);
                centerText("Scan Card", 1, 10);
                display.display();
              }
              
              void showRFIDError() {
                display.clearDisplay();
                centerText("RFID", 1, -10);
                centerText("ERROR", 2, 5);
                display.display();
                Serial.println("RFID Communication Failed!");
              }
              
              void centerText(const char *text, uint8_t textSize, int16_t yOffset) {
                display.setTextSize(textSize);
                display.setTextColor(BLACK);
                
                int16_t x, y;
                uint16_t w, h;
                display.getTextBounds(text, 0, 0, &x, &y, &w, &h);
                
                display.setCursor((display.width() - w) / 2, (display.height() - h) / 2 + yOffset);
                display.print(text);
                display.display();
              }
              
              // RFID Functions
              bool isCardPresent() {
                return rfid.PICC_IsNewCardPresent() && rfid.PICC_ReadCardSerial();
              }
              
              void handleCardDetection() {
                Serial.println("Card detected!");
                showCardDetectedScreen();
                
                String uidString = getUIDString();
                Serial.print("Card UID: ");
                Serial.println(uidString);
                
                displayUID(uidString);
                delay(1500);
                
                if (isAuthorized(rfid.uid.uidByte)) {
                  grantAccess();
                } else {
                  denyAccess();
                }
                
                cleanupRFID();
                showReadyScreen();
              }
              
              String getUIDString() {
                String uid;
                for (byte i = 0; i < rfid.uid.size; i++) {
                  if (rfid.uid.uidByte[i] < 0x10) uid += "0";
                  uid += String(rfid.uid.uidByte[i], HEX);
                  if (i < rfid.uid.size - 1) uid += " ";
                }
                return uid;
              }
              
              void displayUID(String uid) {
                display.clearDisplay();
                centerText("UID:", 1, -15);
                centerText(uid.c_str(), 1, 0);
                display.display();
              }
              
              void showCardDetectedScreen() {
                display.clearDisplay();
                centerText("Card", 1, -10);
                centerText("Detected", 1, 5);
                display.display();
                delay(500);
              }
              
              bool isAuthorized(byte* cardUID) {
                for (byte i = 0; i < 4; i++) {
                  if (cardUID[i] != authorizedUID[i]) {
                    return false;
                  }
                }
                return true;
              }
              
              void cleanupRFID() {
                rfid.PICC_HaltA();
                rfid.PCD_StopCrypto1();
              }
              
              // Access Control Functions
              void grantAccess() {
                Serial.println("ACCESS GRANTED");
                display.clearDisplay();
                centerText("ACCESS", 1, -5);
                centerText("GRANTED", 2, 10);
                display.display();
                
                digitalWrite(LED_PIN, HIGH);
                delay(5000);
                digitalWrite(LED_PIN, LOW);
              }
              
              void denyAccess() {
                Serial.println("ACCESS DENIED");
                display.clearDisplay();
                centerText("ACCESS", 1, -5);
                centerText("DENIED", 2, 10);
                display.display();
                
                for (int i = 0; i < 15; i++) {
                  digitalWrite(LED_PIN, !digitalRead(LED_PIN));
                  delay(100);
                }
                digitalWrite(LED_PIN, LOW);
              }
              
              // Utility Functions
              void blinkLED(int count, int duration) {
                for (int i = 0; i < count; i++) {
                  digitalWrite(LED_PIN, HIGH);
                  delay(duration);
                  digitalWrite(LED_PIN, LOW);
                  delay(duration);
                }
              }
              
              void indicateSystemActive() {
                static unsigned long lastBlink = 0;
                if (millis() - lastBlink > 1000) {
                  digitalWrite(LED_PIN, HIGH);
                  delay(50);
                  digitalWrite(LED_PIN, LOW);
                  lastBlink = millis();
                }
              }

See It In Action

Watch the system grant and deny access

Future Enhancements related to my final project

Multi-User Support

Store multiple authorized UIDs in EEPROM

Audible Feedback

Add a buzzer for access notifications

Cloud Logging

Record access attempts via WiFi

Week 10. Output Devices

What I Built

Parts I Used

Seeed Studio Xiao RP2040

Nokia 5110 LCD

Jumper wires

Libraries I Installed

How I Connected Everything

How My Project Works

My Code

What Each Part of My Code Does

Library Includes:

In the setup() function:

In the main loop():

The centerText() function:

Video Demonstration

What I Built

Hardware Components

XIAO RP2040

MFRC522 RFID

Nokia 5110 LCD

Wiring It All Up

Software Setup

See It In Action

Future Enhancements related to my final project

Multi-User Support

Audible Feedback

Cloud Logging