Next we will demonstrate how to send text and commands using an Arduino microcontroller. You can of course use any microcontroller that has a serial output you can configure for 9600 baud. This demo will show how to set the display size, RGB backlight and create a custom character. For more commands, see below for the full list of supported commands

Grab an Arduino and connect the JST cable to the backpack as follows: Red wire goes to +5V, Black wire goes to Ground, White data wire goes to digital #2. You can change the digital pin later, but stick with #2 for this example and adjust later as desired.

You can download this example from this Github repository.

 

#include "Arduino.h"

#if defined(ARDUINO_ARCH_SAMD) || defined(__SAM3X8E__)
  // use pin 18 with Due, pin 1 with Zero or M0 Pro 
  #define lcd Serial1 
#else
  #include <SoftwareSerial.h>
  // Create a software serial port!
  SoftwareSerial lcd = SoftwareSerial(0,2);
#endif

// for ESP8266 use this SoftwareSerial library: https://github.com/plerup/espsoftwareserial

void setup() {
  lcd.begin(9600);  
  
  // set the size of the display if it isn't 16x2 (you only have to do this once)
  lcd.write(0xFE);
  lcd.write(0xD1);
  lcd.write(16);  // 16 columns
  lcd.write(2);   // 2 rows
  delay(10);       
  // we suggest putting delays after each command to make sure the data 
  // is sent and the LCD is updated.

  // set the contrast, 200 is a good place to start, adjust as desired
  lcd.write(0xFE);
  lcd.write(0x50);
  lcd.write(200);
  delay(10);       
  
  // set the brightness - we'll max it (255 is max brightness)
  lcd.write(0xFE);
  lcd.write(0x99);
  lcd.write(255);
  delay(10);       
  
  // turn off cursors
  lcd.write(0xFE);
  lcd.write(0x4B);
  lcd.write(0xFE);
  lcd.write(0x54);
  
  // create a custom character
  lcd.write(0xFE);
  lcd.write(0x4E);
  lcd.write((uint8_t)0);     // location #0
  lcd.write((uint8_t)0x00);  // 8 bytes of character data
  lcd.write(0x0A);
  lcd.write(0x15);
  lcd.write(0x11);
  lcd.write(0x11);
  lcd.write(0x0A);
  lcd.write(0x04);
  lcd.write((uint8_t)0x00);
  delay(10);   // we suggest putting delays after each command 
  
  // clear screen
  lcd.write(0xFE);
  lcd.write(0x58);
  delay(10);   // we suggest putting delays after each command 
  
  // go 'home'
  lcd.write(0xFE);
  lcd.write(0x48);
  delay(10);   // we suggest putting delays after each command 

  lcd.print("We ");
  lcd.write((uint8_t)0);            // to print the custom character, 'write' the location
  lcd.println(" Arduino!");
  lcd.print("     - Adafruit");
  
  delay(1000);
}

uint8_t red, green, blue;
void loop() {
 // adjust colors 
 for (red = 0; red < 255; red++) {
  lcd.write(0xFE);
  lcd.write(0xD0);
  lcd.write(red); 
  lcd.write((uint8_t)0);
  lcd.write(255 - red);
  delay(10);  // give it some time to adjust the backlight!
 }   

 for (green = 0; green < 255; green++) {
  lcd.write(0xFE);
  lcd.write(0xD0);
  lcd.write(255-green); 
  lcd.write(green);
  lcd.write((uint8_t)0);
  delay(10);  // give it some time to adjust the backlight!
 }   

 for (blue = 0; blue < 255; blue++) {
  lcd.write(0xFE);
  lcd.write(0xD0);
  lcd.write((uint8_t)0); 
  lcd.write(255-blue);
  lcd.write(blue);
  delay(10);  // give it some time to adjust the backlight!
 }   
}
You should see the following, with a color-changing background:

This guide was first published on Feb 06, 2013. It was last updated on Feb 06, 2013.

This page (Testing with TTL Serial) was last updated on Feb 06, 2013.

Text editor powered by tinymce.