Adding a display to an embedded system can bring several benefits, making the device more user-friendly and functional. Displays can be used for diagnostics by showcasing error messages, system logs, or sensor readings in real-time. This can aid in identifying and resolving issues quickly and efficiently.
This post shows how to easily interface an Arduino board with ST7735 TFT display module, how to print texts, numbers, and draw shapes.

Abbreviations:
TFT: Thin-Film Transistor.
LCD: Liquid Crystal Display.
SPI: Serial Peripheral Interface.
MOSI: Master Out Slave In.
MISO: Master In Slave Out.
SCK: Serial Clock
DIY: Do-It-Yourself

The ST7735 TFT Display Module:
The ST7735 is a driver IC commonly used for small, colorful TFT LCD screens. These displays are popular for hobbyist projects due to their low cost, ease of use, and wide availability. This type of displays can be used in various applications including: potable devices, embedded systems, and consumer electronics.
Here are some key features and specifications of the ST7735 display module:

Operating Voltage: Usually 3.3V for the logic and backlight, though some modules include a regulator for 5V input.
Display Size and Resolution: ST7735 displays come in various screen sizes, with the most common being 1.8 inches with a resolution of 128×160 pixels.
Color Depth: 18-bit (262,144 colors) or 16-bit (65,536 colors).
Communication Interface: These displays use SPI serial communication protocol to communicate with the master device.
SD Card slot: Some ST7735 breakout boards include a built-in SD card or microSD card slot. This allows us to store colored bitmaps on the SD card and easily display them on the screen.

The image shows a ST7735 breakout board with integrated component details:

ST7735 Display Pin Configuration:
Typically, the ST7735 display module will have the following pins.

RST: Display reset pin, active low.
CS: Chip Select pin, active low.
D/C: Data/Command pin, select data or command input mode to the display, low for data mode and high for command mode.
DIN (MOSI): Data In, or Master-Out Slave-In pin, SPI data input to the display.
CLK: SPI clock input to the display.
VCC: Power supply pin, 3.3V or 5V.
BL: Backlight LED pin
GND: Ground.

The ST7735 display module shown in the above image can be supplied with 3.3V or 5V depending on the status of jumper J1, closing the jumper bypasses the AMS1117 3.3V LDO regulator and the display will be configured to work with 3.3V only.

Interfacing Arduino with ST7735 TFT Display Circuit:
Hardware circuit diagram of the example is shown below.

The ST7735 display module shown in project circuit diagram has 8 pins: (from right to left): RST (reset), CE (chip enable), DC (or D/C: data/command), DIN (data in), CLK (clock), VCC, BL (back light) and GND (ground).

Hardware Required:
Required components are listed below.

Arduino UNO (or similar) board —> Board details
ST7735 TFT display module
5 x 2k ohm resistor
5 x 1k ohm resistor
Breadboard
Jumper wires

The ST7735 TFT display controller works with 3.3V only (power supply and control signals). The display module is supplied with 5V that comes from the Arduino board. This module has a built-in 3.3V regulator (AMS1117 3.3) which drops the input 5V into 3.3V.

All Arduino UNO board output pins are 5V, connecting a 5V pin to the ST7735 TFT display may damage its controller chip.
To connect the Arduino to the display module, I used voltage divider for each signal line, this means there are 5 voltage dividers. Each voltage divider consists of a 1k and 2k Ohm resistors, this drops the incoming signal voltage from 5V into 3.3V.

So, the ST7735 TFT display is connected to the Arduino board as follows (each one through voltage divider):
RST pin is connected to Arduino digital pin 8,
CS pin is connected to Arduino digital pin 9,
D/C pin is connected to Arduino digital pin 10,
DIN pin is connected to Arduino digital pin 11,
CLK pin is connected to Arduino digital pin 13.

Other pins are connected as follows:
VCC pin is connected to Arduino 5V pin.
GND pin is connected to Arduino GND pin.
BL (LED) pin is connected to Arduino 5V pin.

Pins 13 and 11 are hardware SPI module pins of the ATmega328P microcontroller, respectively for SCK (serial clock) and MOSI (master-out slave-in).

Interfacing Arduino with ST7735 TFT Display Code:
Project Arduino code is just an example of graphics test provided by Adafruit Industries, with some minor modifications.
To be able to compile project Arduino code, two libraries are required from Adafruit Industries:

The first library is a driver for the ST7735 TFT display which can be installed from Arduino IDE library manager (Sketch —> Include Library —> Manage Libraries…, in the search box write “st7735” and install the one from Adafruit).
The second library is Adafruit graphics library which can be installed also from Arduino IDE library manager.
During installation of the Adafruit ST7735 library, Arduino IDE may ask for installing some other libraries form Adafruit Industries (dependencies).

Project code was tested with the following library versions:
Adafruit GFX Library: Version 1.11.9.
Adafruit ST7735 and ST7789 Library: Version 1.10.4.
Adafruit BusIO: Version 1.16.1.

Programming Hints:
The used libraries are included in the Arduino code as shown below:

#include <Adafruit_GFX.h>      // Include Adafruit Core graphics library
#include <Adafruit_ST7735.h>   // Include Adafruit Hardware-specific library for ST7735
#include <SPI.h>               // Include Arduino SPI library

#include <Adafruit_GFX.h> // Include Adafruit Core graphics library

#include <Adafruit_ST7735.h> // Include Adafruit Hardware-specific library for ST7735

#include <SPI.h> // Include Arduino SPI library

The connection between the Arduino UNO board and the ST7735 TFT display is as shown in the above circuit schematic, it is defined in the Arduino code as shown below:

// Define ST7735 display pin connection
#define TFT_RST     8   // Or set to -1 and connect to Arduino RESET pin
#define TFT_CS      9   
#define TFT_DC      10

// Define ST7735 display pin connection

#define TFT_RST 8 // Or set to -1 and connect to Arduino RESET pin

#define TFT_CS 9

#define TFT_DC 10

The initialization of the ST7789 TFT display library with the connections previously defined:

// Initialize the ST7735 display library with previously defined connections
Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);

1 2	// Initialize the ST7735 display library with previously defined connections Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);

The ST7735 display must be initialized before any print operation, if the initialization failed then the display will show only black screen. The initialization function of the display is the one below:

// Initialize the ST7735 TFT display
tft.initR(INITR_BLACKTAB);      // Init ST7735S chip, black tab

1 2	// Initialize the ST7735 TFT display tft.initR(INITR_BLACKTAB); // Init ST7735S chip, black tab

For more details about Arduino SPI communication, see the following page:
Arduino & Serial Peripheral Interface (SPI)

Rest of code is described through comments.

Full Arduino code:
Example Arduino code can be browsed through the below GitHub link:
ST7735-Graphics-Test

/**************************************************************************************

 * Interfacing Arduino board with ST7735 TFT display (128x160 pixel).
 * This is a free software with NO WARRANTY.
 * https://simple-circuit.com/

/**************************************************************************************/

#include <Adafruit_GFX.h>      // Include Adafruit Core graphics library
#include <Adafruit_ST7735.h>   // Include Adafruit Hardware-specific library for ST7735 display
#include <SPI.h>               // Include Arduino SPI library

// Define ST7735 display pin connection
#define TFT_RST     8   // Or set to -1 and connect to Arduino RESET pin
#define TFT_CS      9   
#define TFT_DC      10

// Initialize the ST7735 display library with previously defined connections
Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);

float p = 3.1415926;

void setup(void) {
  Serial.begin(9600);
  Serial.print(F("Hello! ST77xx TFT Test"));

  // Initialize the ST7735 TFT display
  tft.initR(INITR_BLACKTAB);      // Init ST7735S chip, black tab

  Serial.println(F("Initialized"));

  uint16_t time = millis();
  tft.fillScreen(ST77XX_BLACK);
  time = millis() - time;

  Serial.println(time, DEC);
  delay(500);

  // large block of text
  tft.fillScreen(ST77XX_BLACK);
  testdrawtext("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ", ST77XX_WHITE);
  delay(1000);

  // tft print function!
  tftPrintTest();
  delay(4000);

  // a single pixel
  tft.drawPixel(tft.width()/2, tft.height()/2, ST77XX_GREEN);
  delay(500);

  // line draw test
  testlines(ST77XX_YELLOW);
  delay(500);

  // optimized lines
  testfastlines(ST77XX_RED, ST77XX_BLUE);
  delay(500);

  testdrawrects(ST77XX_GREEN);
  delay(500);

  testfillrects(ST77XX_YELLOW, ST77XX_MAGENTA);
  delay(500);

  tft.fillScreen(ST77XX_BLACK);
  testfillcircles(10, ST77XX_BLUE);
  testdrawcircles(10, ST77XX_WHITE);
  delay(500);

  testroundrects();
  delay(500);

  testtriangles();
  delay(500);

  mediabuttons();
  delay(500);

  Serial.println("done");
  delay(1000);
}

void loop() {
  tft.invertDisplay(true);
  delay(500);
  tft.invertDisplay(false);
  delay(500);
}

void testlines(uint16_t color) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(0, 0, x, tft.height()-1, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(0, 0, tft.width()-1, y, color);
    delay(0);
  }

  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(tft.width()-1, 0, x, tft.height()-1, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(tft.width()-1, 0, 0, y, color);
    delay(0);
  }

  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(0, tft.height()-1, x, 0, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(0, tft.height()-1, tft.width()-1, y, color);
    delay(0);
  }

  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawLine(tft.width()-1, tft.height()-1, x, 0, color);
    delay(0);
  }
  for (int16_t y=0; y < tft.height(); y+=6) {
    tft.drawLine(tft.width()-1, tft.height()-1, 0, y, color);
    delay(0);
  }
}

void testdrawtext(char *text, uint16_t color) {
  tft.setCursor(0, 0);
  tft.setTextColor(color);
  tft.setTextWrap(true);
  tft.print(text);
}

void testfastlines(uint16_t color1, uint16_t color2) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t y=0; y < tft.height(); y+=5) {
    tft.drawFastHLine(0, y, tft.width(), color1);
  }
  for (int16_t x=0; x < tft.width(); x+=5) {
    tft.drawFastVLine(x, 0, tft.height(), color2);
  }
}

void testdrawrects(uint16_t color) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=0; x < tft.width(); x+=6) {
    tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color);
  }
}

void testfillrects(uint16_t color1, uint16_t color2) {
  tft.fillScreen(ST77XX_BLACK);
  for (int16_t x=tft.width()-1; x > 6; x-=6) {
    tft.fillRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color1);
    tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color2);
  }
}

void testfillcircles(uint8_t radius, uint16_t color) {
  for (int16_t x=radius; x < tft.width(); x+=radius*2) {
    for (int16_t y=radius; y < tft.height(); y+=radius*2) {
      tft.fillCircle(x, y, radius, color);
    }
  }
}

void testdrawcircles(uint8_t radius, uint16_t color) {
  for (int16_t x=0; x < tft.width()+radius; x+=radius*2) {
    for (int16_t y=0; y < tft.height()+radius; y+=radius*2) {
      tft.drawCircle(x, y, radius, color);
    }
  }
}

void testtriangles() {
  tft.fillScreen(ST77XX_BLACK);
  uint16_t color = 0xF800;
  int t;
  int w = tft.width()/2;
  int x = tft.height()-1;
  int y = 0;
  int z = tft.width();
  for(t = 0 ; t <= 15; t++) {
    tft.drawTriangle(w, y, y, x, z, x, color);
    x-=4;
    y+=4;
    z-=4;
    color+=100;
  }
}

void testroundrects() {
  tft.fillScreen(ST77XX_BLACK);
  uint16_t color = 100;
  int i;
  int t;
  for(t = 0 ; t <= 4; t+=1) {
    int x = 0;
    int y = 0;
    int w = tft.width()-2;
    int h = tft.height()-2;
    for(i = 0 ; i <= 16; i+=1) {
      tft.drawRoundRect(x, y, w, h, 5, color);
      x+=2;
      y+=3;
      w-=4;
      h-=6;
      color+=1100;
    }
    color+=100;
  }
}

void tftPrintTest() {
  tft.setTextWrap(false);
  tft.fillScreen(ST77XX_BLACK);
  tft.setCursor(0, 30);
  tft.setTextColor(ST77XX_RED);
  tft.setTextSize(1);
  tft.println("Hello World!");
  tft.setTextColor(ST77XX_YELLOW);
  tft.setTextSize(2);
  tft.println("Hello World!");
  tft.setTextColor(ST77XX_GREEN);
  tft.setTextSize(3);
  tft.println("Hello World!");
  tft.setTextColor(ST77XX_BLUE);
  tft.setTextSize(4);
  tft.print(1234.567);
  delay(1500);
  tft.setCursor(0, 0);
  tft.fillScreen(ST77XX_BLACK);
  tft.setTextColor(ST77XX_WHITE);
  tft.setTextSize(0);
  tft.println("Hello World!");
  tft.setTextSize(1);
  tft.setTextColor(ST77XX_GREEN);
  tft.print(p, 6);
  tft.println(" Want pi?");
  tft.println(" ");
  tft.print(8675309, HEX); // print 8,675,309 out in HEX!
  tft.println(" Print HEX!");
  tft.println(" ");
  tft.setTextColor(ST77XX_WHITE);
  tft.println("Sketch has been");
  tft.println("running for: ");
  tft.setTextColor(ST77XX_MAGENTA);
  tft.print(millis() / 1000);
  tft.setTextColor(ST77XX_WHITE);
  tft.print(" seconds.");
}

void mediabuttons() {
  // play
  tft.fillScreen(ST77XX_BLACK);
  tft.fillRoundRect(25, 10, 78, 60, 8, ST77XX_WHITE);
  tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_RED);
  delay(500);
  // pause
  tft.fillRoundRect(25, 90, 78, 60, 8, ST77XX_WHITE);
  tft.fillRoundRect(39, 98, 20, 45, 5, ST77XX_GREEN);
  tft.fillRoundRect(69, 98, 20, 45, 5, ST77XX_GREEN);
  delay(500);
  // play color
  tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_BLUE);
  delay(50);
  // pause color
  tft.fillRoundRect(39, 98, 20, 45, 5, ST77XX_RED);
  tft.fillRoundRect(69, 98, 20, 45, 5, ST77XX_RED);
  // play color
  tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_GREEN);
}

/**************************************************************************
  This is a library for several Adafruit displays based on ST77* drivers.

  Works with the Adafruit 1.8" TFT Breakout w/SD card
    ----> http://www.adafruit.com/products/358
  The 1.8" TFT shield
    ----> https://www.adafruit.com/product/802
  The 1.44" TFT breakout
    ----> https://www.adafruit.com/product/2088
  The 1.14" TFT breakout
  ----> https://www.adafruit.com/product/4383
  The 1.3" TFT breakout
  ----> https://www.adafruit.com/product/4313
  The 1.54" TFT breakout
    ----> https://www.adafruit.com/product/3787
  The 1.69" TFT breakout
    ----> https://www.adafruit.com/product/5206
  The 2.0" TFT breakout
    ----> https://www.adafruit.com/product/4311
  as well as Adafruit raw 1.8" TFT display
    ----> http://www.adafruit.com/products/618

  Check out the links above for our tutorials and wiring diagrams.
  These displays use SPI to communicate, 4 or 5 pins are required to
  interface (RST is optional).

  Adafruit invests time and resources providing this open source code,
  please support Adafruit and open-source hardware by purchasing
  products from Adafruit!

  Written by Limor Fried/Ladyada for Adafruit Industries.
  MIT license, all text above must be included in any redistribution
 **************************************************************************/

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/**************************************************************************************

* Interfacing Arduino board with ST7735 TFT display (128x160 pixel).

* This is a free software with NO WARRANTY.

* https://simple-circuit.com/

/**************************************************************************************/

#include <Adafruit_GFX.h> // Include Adafruit Core graphics library

#include <Adafruit_ST7735.h> // Include Adafruit Hardware-specific library for ST7735 display

#include <SPI.h> // Include Arduino SPI library

// Define ST7735 display pin connection

#define TFT_RST 8 // Or set to -1 and connect to Arduino RESET pin

#define TFT_CS 9

#define TFT_DC 10

// Initialize the ST7735 display library with previously defined connections

Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);

float p = 3.1415926;

void setup(void) {

Serial.begin(9600);

Serial.print(F("Hello! ST77xx TFT Test"));

// Initialize the ST7735 TFT display

tft.initR(INITR_BLACKTAB); // Init ST7735S chip, black tab

Serial.println(F("Initialized"));

uint16_t time = millis();

tft.fillScreen(ST77XX_BLACK);

time = millis() - time;

Serial.println(time, DEC);

delay(500);

// large block of text

tft.fillScreen(ST77XX_BLACK);

testdrawtext("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ", ST77XX_WHITE);

delay(1000);

// tft print function!

tftPrintTest();

delay(4000);

// a single pixel

tft.drawPixel(tft.width()/2, tft.height()/2, ST77XX_GREEN);

delay(500);

// line draw test

testlines(ST77XX_YELLOW);

delay(500);

// optimized lines

testfastlines(ST77XX_RED, ST77XX_BLUE);

delay(500);

testdrawrects(ST77XX_GREEN);

delay(500);

testfillrects(ST77XX_YELLOW, ST77XX_MAGENTA);

delay(500);

tft.fillScreen(ST77XX_BLACK);

testfillcircles(10, ST77XX_BLUE);

testdrawcircles(10, ST77XX_WHITE);

delay(500);

testroundrects();

delay(500);

testtriangles();

delay(500);

mediabuttons();

delay(500);

Serial.println("done");

delay(1000);

}

void loop() {

tft.invertDisplay(true);

delay(500);

tft.invertDisplay(false);

delay(500);

}

void testlines(uint16_t color) {

tft.fillScreen(ST77XX_BLACK);

for (int16_t x=0; x < tft.width(); x+=6) {

tft.drawLine(0, 0, x, tft.height()-1, color);

delay(0);

}

for (int16_t y=0; y < tft.height(); y+=6) {

tft.drawLine(0, 0, tft.width()-1, y, color);

delay(0);

}

tft.fillScreen(ST77XX_BLACK);

for (int16_t x=0; x < tft.width(); x+=6) {

tft.drawLine(tft.width()-1, 0, x, tft.height()-1, color);

delay(0);

}

for (int16_t y=0; y < tft.height(); y+=6) {

tft.drawLine(tft.width()-1, 0, 0, y, color);

delay(0);

}

tft.fillScreen(ST77XX_BLACK);

for (int16_t x=0; x < tft.width(); x+=6) {

tft.drawLine(0, tft.height()-1, x, 0, color);

delay(0);

}

for (int16_t y=0; y < tft.height(); y+=6) {

tft.drawLine(0, tft.height()-1, tft.width()-1, y, color);

delay(0);

}

tft.fillScreen(ST77XX_BLACK);

for (int16_t x=0; x < tft.width(); x+=6) {

tft.drawLine(tft.width()-1, tft.height()-1, x, 0, color);

delay(0);

}

for (int16_t y=0; y < tft.height(); y+=6) {

tft.drawLine(tft.width()-1, tft.height()-1, 0, y, color);

delay(0);

}

void testdrawtext(char *text, uint16_t color) {

tft.setCursor(0, 0);

tft.setTextColor(color);

tft.setTextWrap(true);

tft.print(text);

}

void testfastlines(uint16_t color1, uint16_t color2) {

tft.fillScreen(ST77XX_BLACK);

for (int16_t y=0; y < tft.height(); y+=5) {

tft.drawFastHLine(0, y, tft.width(), color1);

}

for (int16_t x=0; x < tft.width(); x+=5) {

tft.drawFastVLine(x, 0, tft.height(), color2);

}

void testdrawrects(uint16_t color) {

tft.fillScreen(ST77XX_BLACK);

for (int16_t x=0; x < tft.width(); x+=6) {

tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color);

}

void testfillrects(uint16_t color1, uint16_t color2) {

tft.fillScreen(ST77XX_BLACK);

for (int16_t x=tft.width()-1; x > 6; x-=6) {

tft.fillRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color1);

tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color2);

}

void testfillcircles(uint8_t radius, uint16_t color) {

for (int16_t x=radius; x < tft.width(); x+=radius*2) {

for (int16_t y=radius; y < tft.height(); y+=radius*2) {

tft.fillCircle(x, y, radius, color);

}

void testdrawcircles(uint8_t radius, uint16_t color) {

for (int16_t x=0; x < tft.width()+radius; x+=radius*2) {

for (int16_t y=0; y < tft.height()+radius; y+=radius*2) {

tft.drawCircle(x, y, radius, color);

}

void testtriangles() {

tft.fillScreen(ST77XX_BLACK);

uint16_t color = 0xF800;

int t;

int w = tft.width()/2;

int x = tft.height()-1;

int y = 0;

int z = tft.width();

for(t = 0 ; t <= 15; t++) {

tft.drawTriangle(w, y, y, x, z, x, color);

x-=4;

y+=4;

z-=4;

color+=100;

}

void testroundrects() {

tft.fillScreen(ST77XX_BLACK);

uint16_t color = 100;

int i;

int t;

for(t = 0 ; t <= 4; t+=1) {

int x = 0;

int y = 0;

int w = tft.width()-2;

int h = tft.height()-2;

for(i = 0 ; i <= 16; i+=1) {

tft.drawRoundRect(x, y, w, h, 5, color);

x+=2;

y+=3;

w-=4;

h-=6;

color+=1100;

}

color+=100;

}

void tftPrintTest() {

tft.setTextWrap(false);

tft.fillScreen(ST77XX_BLACK);

tft.setCursor(0, 30);

tft.setTextColor(ST77XX_RED);

tft.setTextSize(1);

tft.println("Hello World!");

tft.setTextColor(ST77XX_YELLOW);

tft.setTextSize(2);

tft.println("Hello World!");

tft.setTextColor(ST77XX_GREEN);

tft.setTextSize(3);

tft.println("Hello World!");

tft.setTextColor(ST77XX_BLUE);

tft.setTextSize(4);

tft.print(1234.567);

delay(1500);

tft.setCursor(0, 0);

tft.fillScreen(ST77XX_BLACK);

tft.setTextColor(ST77XX_WHITE);

tft.setTextSize(0);

tft.println("Hello World!");

tft.setTextSize(1);

tft.setTextColor(ST77XX_GREEN);

tft.print(p, 6);

tft.println(" Want pi?");

tft.println(" ");

tft.print(8675309, HEX); // print 8,675,309 out in HEX!

tft.println(" Print HEX!");

tft.println(" ");

tft.setTextColor(ST77XX_WHITE);

tft.println("Sketch has been");

tft.println("running for: ");

tft.setTextColor(ST77XX_MAGENTA);

tft.print(millis() / 1000);

tft.setTextColor(ST77XX_WHITE);

tft.print(" seconds.");

}

void mediabuttons() {

// play

tft.fillScreen(ST77XX_BLACK);

tft.fillRoundRect(25, 10, 78, 60, 8, ST77XX_WHITE);

tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_RED);

delay(500);

// pause

tft.fillRoundRect(25, 90, 78, 60, 8, ST77XX_WHITE);

tft.fillRoundRect(39, 98, 20, 45, 5, ST77XX_GREEN);

tft.fillRoundRect(69, 98, 20, 45, 5, ST77XX_GREEN);

delay(500);

// play color

tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_BLUE);

delay(50);

// pause color

tft.fillRoundRect(39, 98, 20, 45, 5, ST77XX_RED);

tft.fillRoundRect(69, 98, 20, 45, 5, ST77XX_RED);

// play color

tft.fillTriangle(42, 20, 42, 60, 90, 40, ST77XX_GREEN);

}

/**************************************************************************

This is a library for several Adafruit displays based on ST77* drivers.

Works with the Adafruit 1.8" TFT Breakout w/SD card

----> http://www.adafruit.com/products/358

The 1.8" TFT shield

----> https://www.adafruit.com/product/802

The 1.44" TFT breakout

----> https://www.adafruit.com/product/2088

The 1.14" TFT breakout

----> https://www.adafruit.com/product/4383

The 1.3" TFT breakout

----> https://www.adafruit.com/product/4313

The 1.54" TFT breakout

----> https://www.adafruit.com/product/3787

The 1.69" TFT breakout

----> https://www.adafruit.com/product/5206

The 2.0" TFT breakout

----> https://www.adafruit.com/product/4311

as well as Adafruit raw 1.8" TFT display

----> http://www.adafruit.com/products/618

Check out the links above for our tutorials and wiring diagrams.

These displays use SPI to communicate, 4 or 5 pins are required to

interface (RST is optional).

Adafruit invests time and resources providing this open source code,

please support Adafruit and open-source hardware by purchasing

products from Adafruit!

Written by Limor Fried/Ladyada for Adafruit Industries.

MIT license, all text above must be included in any redistribution

**************************************************************************/

Interfacing Arduino with ST7735 TFT Display Video:
The video below shows my DIY hardware test circuit of an Arduino NANO board with ST7735 TFT display:

Arduino with ST7735 TFT Display Proteus Simulation Video:
The video below shows Proteus simulation of Arduino UNO board with ST7735 TFT display.
Note that Proteus simulation circuit is not the same as real hardware circuit, project hardware circuit diagram is shown above.

Proteus simulation file download link is below, use version 8.15 or higher to open it:
Arduino and ST7735 TFT Proteus simulation