Error In Displaying Emoji On The ST7920 128x64 LCD

[DALVI12]

I Am Trying to Display Emoji On ST7920 128X64 LCD Display with Arduino Uno. But when i try to do it, it just shows a blank screen with black light ON, If I remove the emoji function and only keep the text function, then it works.

PIN CONNECTION : PIN 1 (GND) - GND PIN 2 (VCC) - 5V PIN 3 (V0) - POT WIPER
PIN 4 (RS) - D10 PIN 5 (R/W) - D11 PIN 6 (E) - D13 PIN 15 (PSB) - GND PIN 17 (RST) - D8 PIN 19 (BLA) - 3.3V PIN 20 (BLK) - GND

[olikraus]

Some code would be helpful.

[DALVI12]

now the case is little different it prints but not as mention in the code ;

code :

include

include

include

include

include

include

U8G2_ST7920_128X64_F_SW_SPI u8g2(U8G2_R0, / clock=/ 13, / data=/ 11, / CS=/ 10, / reset=/ 8); // Software SPI

define DHT11_PIN 7

define BMP280_ADDRESS 0x76

Adafruit_BMP280 bmp; // BMP280 sensor (I2C) BH1750 lightMeter; // BH1750 sensor (I2C) DHT dht(DHT11_PIN, DHT11); // Initialize DHT sensor

const int MQ135_PIN = A0; const int UV_PIN = A1; // Connect the UV sensor to analog pin A1 const int SOIL_MOISTURE_PIN = A2; // Connect the soil moisture sensor to analog pin A2 const int POTENTIOMETER_PIN = A3; // Connect the potentiometer to analog pin A3

unsigned long previousMillis = 0; const long interval = 500; // interval at which to read sensors (milliseconds)

unsigned long int avgValue; // Store the average value of the sensor feedback int buf[10], temp;

void setup() { Serial.begin(9600); while (!Serial) delay(100); // wait for serial monitor

Wire.begin(); // Initialize the I2C bus

if (!bmp.begin(BMP280_ADDRESS)) { Serial.println(F("Could not find a valid BMP280 sensor, check wiring or try a different address!")); Serial.print("SensorID was: 0x"); Serial.println(bmp.sensorID(), 16); Serial.print(" ID of 0xFF probably means a bad address, a BMP 180 or BMP 085\n"); Serial.print(" ID of 0x56-0x58 represents a BMP 280,\n"); Serial.print(" ID of 0x60 represents a BME 280.\n"); Serial.print(" ID of 0x61 represents a BME 680.\n"); while (1) delay(10); }

bmp.setSampling(Adafruit_BMP280::MODE_NORMAL, Adafruit_BMP280::SAMPLING_X2, Adafruit_BMP280::SAMPLING_X16, Adafruit_BMP280::FILTER_X16, Adafruit_BMP280::STANDBY_MS_500); // Set BMP280 settings

lightMeter.begin(); // Initialize BH1750 sensor dht.begin(); // Initialize DHT sensor

pinMode(13, OUTPUT); Serial.println("Ready"); // Test the serial monitor u8g2.begin(); }

void loop() { unsigned long currentMillis = millis();

if (currentMillis - previousMillis >= interval) { previousMillis = currentMillis;

// Reading temperature, pressure, and altitude from BMP280 sensor
float tempBMP = bmp.readTemperature();
float pressure = bmp.readPressure();
float altitude = bmp.readAltitude(1013.25);

// Reading light level from BH1750 sensor
float lux = lightMeter.readLightLevel();

// Reading temperature and humidity from DHT11 sensor
float tempDHT = dht.readTemperature();
float humDHT = dht.readHumidity();

// Reading air quality from MQ135 sensor
int sensorDataMQ135 = analogRead(MQ135_PIN);

// Reading UV index from GUVA-S12SD UV Module
int sensorDataUV = analogRead(UV_PIN);
float uvIndex = map(sensorDataUV, 0, 1023, 0, 15);

// Reading soil moisture level
int sensorDataSoil = analogRead(SOIL_MOISTURE_PIN);

// Adjust vertical position based on potentiometer reading
int potValue = analogRead(POTENTIOMETER_PIN);
int verticalPos = map(potValue, 0, 1023, 0, 64); // Map potentiometer value to display height

// Print individual sensor readings with reactions
u8g2.clearBuffer();
u8g2.setFont(u8g2_font_profont10_tf);  // Use a smaller font size

// Temperature from DHT11
u8g2.drawStr(1, -35 + verticalPos, "Temp (DHT11):");
u8g2.setCursor(80, -35 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForTemperature(tempDHT)); // Print temperature emoji instead of value

// Humidity
u8g2.drawStr(2, -25 + verticalPos, "Humidity:");
u8g2.setCursor(60, -25 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForHumidity(humDHT)); // Print humidity emoji instead of value

// Light level
u8g2.drawStr(2, -15 + verticalPos, "Light:");
u8g2.setCursor(60, -15 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForLightLevel(lux)); // Print light level emoji instead of value

// Soil Moisture level
u8g2.drawStr(2, -5 + verticalPos, "Soil Moisture:");
u8g2.setCursor(80, -5 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForSoilMoisture(sensorDataSoil)); // Print soil moisture emoji instead of value

// Air Quality
u8g2.drawStr(2, 5 + verticalPos, "Air Quality:");
u8g2.setCursor(70, 5 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForAirQuality(sensorDataMQ135)); // Print air quality emoji instead of value

// Pressure
u8g2.drawStr(2, 15 + verticalPos, "Pressure:");
u8g2.setCursor(60, 15 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForPressure(pressure)); // Print pressure emoji instead of value

// Altitude
u8g2.drawStr(2, 25 + verticalPos, "Altitude:");
u8g2.setCursor(60, 25 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForAltitude(altitude)); // Print altitude emoji instead of value

// UV Index
u8g2.drawStr(2, 35 + verticalPos, "UV Index:");
u8g2.setCursor(70, 35 + verticalPos);  // Adjust X coordinate
u8g2.print(getEmojiForUVIndex(uvIndex)); // Print UV index emoji instead of value

u8g2.sendBuffer();

} }

// Function to map temperature value to emoji char getEmojiForTemperature(float temp) { if (temp < 10) { return '❄'; // Cold emoji } else if (temp >= 10 && temp < 20) { return '😊'; // Pleasant emoji } else { return '☀'; // Hot emoji } }

// Function to map humidity value to emoji char getEmojiForHumidity(float humidity) { if (humidity < 30) { return '😓'; // Low humidity emoji } else if (humidity >= 30 && humidity <= 70) { return '😊'; // Comfortable humidity emoji } else { return '💧'; // High humidity emoji } }

// Function to map light level value to emoji char getEmojiForLightLevel(float lux) { if (lux < 100) { return '🌑'; // Dark emoji } else if (lux >= 100 && lux < 1000) { return '🌤'; // Bright emoji } else { return '☀'; // Very bright emoji } }

// Function to map soil moisture level to emoji char getEmojiForSoilMoisture(int moisture) { if (moisture < 300) { return '🌵'; // Dry emoji } else if (moisture >= 300 && moisture <= 700) { return '🌱'; // Moist emoji } else { return '💧'; // Wet emoji } }

// Function to map air quality value to emoji char getEmojiForAirQuality(int airQuality) { if (airQuality < 200) { return '😷'; // Poor air quality emoji } else if (airQuality >= 200 && airQuality < 400) { return '😐'; // Moderate air quality emoji } else { return '😊'; // Good air quality emoji } }

// Function to map pressure value to emoji char getEmojiForPressure(float pressure) { if (pressure < 100000) { return '🌀'; // Low pressure emoji } else if (pressure >= 100000 && pressure < 101500) { return '😊'; // Normal pressure emoji } else { return '🌞'; // High pressure emoji } }

// Function to map altitude value to emoji char getEmojiForAltitude(float altitude) { if (altitude < 0) { return '🌊'; // Below sea level emoji } else if (altitude >= 0 && altitude < 100) { return '🏔'; // Low altitude emoji } else { return '🌌'; // High altitude emoji } }

// Function to map UV index value to emoji char getEmojiForUVIndex(float uvIndex) { if (uvIndex < 3) { return '🌑'; // Low UV index emoji } else if (uvIndex >= 3 && uvIndex < 6) { return '🌤'; // Moderate UV index emoji } else { return '☀'; // High UV index emoji } }

[olikraus]

Did you check whether the emoji are included in the font? Another point is, that the emoji are mapped to different glyph numbers in u8g2. So: Please select a font first, then carefully calculate the glyph number for the desired emoji and use the drawGlyph function to draw the emoji.

[DALVI12]

where can i find the list of emoji and symbols like % with glyph number ?

[olikraus]

You need to look at the fonts: https://github.com/olikraus/u8g2/wiki/fntgrp

First thing is to select a font which contains the desired glyph (emoji). Then derive the glyph number from the font picture.

Lets consider the "emoticons21" font: https://github.com/olikraus/u8g2/wiki/fntgrpu8g#emoticons21

The first emoji in the first row has the number 32 (as written at the beginning of the row). The second emoji would then have the number 33. The first emoji in the second row has the number 48.

You can use the "\xNN" hex notation inside a string to print the emoji, so to draw the first emoji you can use drawStr("\x20"); (0x20 is the hex code for 32)

Other emoji are part of unicode: https://github.com/olikraus/u8g2/wiki/fntgrpunifont

Maybe you also find suitable icons here: https://github.com/olikraus/u8g2/wiki/fntgrpstreamline