Code

//WWW.EKOSTRA.COM
// Include the library
#include <TM1637Display.h>

// Define the connections pins
#define CLK 3
#define DIO 4

// Create a display object of type TM1637Display
TM1637Display display = TM1637Display(CLK, DIO);

// Create an array that turns all segments ON
const uint8_t allON[] = {0xff, 0xff, 0xff, 0xff};

// Create an array that turns all segments OFF
const uint8_t allOFF[] = {0x00, 0x00, 0x00, 0x00};

// Create an array that sets individual segments per digit to display the word "dOnE"
const uint8_t done[] = {
  SEG_B | SEG_C | SEG_D | SEG_E | SEG_G,           // d
  SEG_A | SEG_B | SEG_C | SEG_D | SEG_E | SEG_F,   // O
  SEG_C | SEG_E | SEG_G,                           // n
  SEG_A | SEG_D | SEG_E | SEG_F | SEG_G            // E
};

// Create degree celsius symbol
const uint8_t celsius[] = {
  SEG_A | SEG_B | SEG_F | SEG_G,  // Degree symbol
  SEG_A | SEG_D | SEG_E | SEG_F   // C
};

void setup() {

}

void loop() {
    // Set the brightness to 5 (0=dimmest 7=brightest)
    display.setBrightness(5);

    // Set all segments ON
    display.setSegments(allON);

    delay(2000);
    display.clear();

    // Show counter 0-9
    int i;
    for (i = 0; i < 10; i++) {
        display.showNumberDec(i);
        delay(50);
    }

    delay(2000);
    display.clear();

    display.showNumberDec(-12);			// Prints _-12
    delay(2000);
    display.clear();
    
    display.showNumberDec(-999);		// Prints -999
    delay(2000);
    display.clear();
    
    display.showNumberDec(31, false);	// Prints __31
    delay(2000);
    display.clear();
    
    display.showNumberDec(31, true);	// Prints 0031
    delay(2000);
    display.clear();
    
    display.showNumberDec(14, false, 2, 1);	// Prints _14_
    delay(2000);
    display.clear();
    
    display.showNumberDec(-5, false, 3, 0);	// Prints _-5_
    delay(2000);
    display.clear();

    // Prints 12:34
    display.showNumberDecEx(1234, 0b11100000, false, 4, 0);

    delay(2000);
    display.clear();

    // Prints 15°C
    int temperature = 15;
    display.showNumberDec(temperature, false, 2, 0);
    display.setSegments(celsius, 2, 2);

    delay(2000);
    display.clear();
    
    // Prints dOnE
    display.setSegments(done);

    while(1);
}