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:
