Example Code for Raspberry Pi - Set LCD Color (Python)

Hardware Preparation

• Raspberry Pi 4B x 1
• RGB LCD KeyPad HAT x1
• HDMI Cable x1
• Display x1
• Keyboard and Mouse x1

Software Preparation

• Raspberry Pi OS
• Download DFRobot_RGB1602_RaspberryPi library (via GitHub or USB)

Software Preparation

• Raspberry Pi OS
• Install RPi.GPIO and rgb1602 libraries (included in the DFRobot_RGB1602_RaspberryPi library)
• Download DFRobot_RGB1602_RaspberryPi library

Wiring Diagram

1. Install jumper caps to connect GPIO pins to the buttons (e.g., GPIO16 to the Select button).
2. Install the RGB LCD KeyPad HAT onto the Raspberry Pi.

Other Preparation Work

1. Enable I2C on Raspberry Pi:
   Input sudo raspi-config in the terminal, then select Interfacing Options (or Advanced Options) → I2C → Yes → OK → Finish.
   
   
   
   
   

2. Detect the I2C address of the HAT:
   Run sudo i2cdetect -y 1 to confirm the device is recognized.
   

3. Download the library:

   • Via GitHub: git clone https://github.com/DFRobot/DFRobot_RGB1602_RaspberryPi.git
   • Via USB: Download the library to a USB drive and copy it to the Raspberry Pi.

Sample Code

import sys
    sys.path.append('../')
    import RPi.GPIO as GPIO
    import rgb1602
    import time
    lcd = rgb1602.RGB1602(16,2)
    GPIO.setmode(GPIO.BCM)
    # Define keys
    lcd_key     = 0
    key_in  = 0
    btnRIGHT  = 0
    btnUP     = 1
    btnDOWN   = 2
    btnLEFT   = 3
    btnSELECT = 4
    GPIO.setup(16, GPIO.IN)
    GPIO.setup(17, GPIO.IN)
    GPIO.setup(18, GPIO.IN)
    GPIO.setup(19, GPIO.IN)
    GPIO.setup(20, GPIO.IN)
    #Read the key value
    def read_LCD_buttons():
      key_in16 = GPIO.input(16)
      key_in17 = GPIO.input(17)
      key_in18 = GPIO.input(18)
      key_in19 = GPIO.input(19)
      key_in20 = GPIO.input(20)

      if (key_in16 == 1):
        return btnSELECT
      if (key_in17 == 1):
        return btnUP
      if (key_in18 == 1):
        return btnDOWN
      if (key_in19 == 1):
        return btnLEFT
      if (key_in20 == 1):
        return btnRIGHT
    lcd.setCursor(0,0)
    lcd.print("Push the buttons"); #print“Push the buttons”
    while True:
      lcd.setCursor(0,1)
      lcd_key = read_LCD_buttons()  #  Reading keys
      if (lcd_key == btnRIGHT):
        lcd.print("RIGHT ")
      elif (lcd_key == btnLEFT):
        lcd.print("LEFT  ")
      elif (lcd_key == btnUP):
        lcd.print("UP    ")
      elif (lcd_key == btnDOWN):
        lcd.print("DOWN  ")
      elif (lcd_key == btnSELECT):
        lcd.print("SELECT")