1. Development board
Arduino nano（168p）
2. screen
lcd1602, if you don't add an adapter board, it will take up a lot of io, and you need to add an adjustable resistor to adjust the contrast.
3. Adapter board
The pcf8574T adapter board is used here, which only occupies two io ports through the i2c protocol, and integrates adjustable resistors, which is very convenient to use.
4. Libraries and Code
Download lcd_i2c in Arduino, pay attention to the author, don't make a mistake.
The code is in the example, you can modify it yourself.
#include <LCD_I2C.h>
LCD_I2C lcd(0x27, 16, 2); // Default address of most PCF8574 modules, change according
void setup()
{
lcd.begin(); // If you are using more I2C devices using the Wire library use lcd.begin(false)
// this stop the library(LCD_I2C) from calling Wire.begin()
lcd.backlight();
}
void loop()
{
lcd.print(" Hello"); // You can make spaces using well... spaces
lcd.setCursor(5, 1); // Or setting the cursor in the desired position.
lcd.print("World!");
delay(500);
// Flashing the backlight
for (int i = 0; i < 5; ++i)
{
lcd.backlight();
delay(50);
lcd.noBacklight();
delay(50);
}
lcd.backlight();
lcd.clear();
delay(500);
}5. Connection
| development board | Screen |
| A4 | SDA |
| A5 | SCL |
| GND | GDN |
| 3.3-5V | VCC |