Arduino Nano ESP32 - TM1637 4-Digit 7-Segment Display
Welcome to this hands-on workshop where we connect a TM1637 4-digit 7-segment display to an Arduino Nano ESP32. The Nano ESP32 is built around the ESP32-S3 chip, giving you Wi-Fi, Bluetooth Low Energy, and dual-core processing power - all packed into the familiar Nano form factor with a USB-C connector. The TM1637 module runs on 3.3V, so it pairs directly with the Nano ESP32 without any level shifting.
In this workshop you will:
- Wire the TM1637 display to the Arduino Nano ESP32.
- Display integers, text, and temperature on the 7-segment display.
- Show time in HH:MM format with a blinking colon.
- Control individual digits and adjust brightness.
Hardware Preparation
Or you can buy the following kits:
| 1 | × | DIYables Sensor Kit (18 sensors/displays) |
Disclosure: Some of the links provided in this section are Amazon affiliate links. We may receive a commission for any purchases made through these links at no additional cost to you.
Additionally, some of these links are for products from our own brand, DIYables .
Additionally, some of these links are for products from our own brand, DIYables .
Overview of the TM1637 Display Module
The TM1637 is a specialized LED driver IC that handles the multiplexing of four 7-segment digits on its own. Data transfer uses a 2-wire serial protocol through CLK and DIO pins. The chip stores display content in internal registers, so whatever you send to it stays on screen without the microcontroller having to refresh it continuously.
Module capabilities:
- 4 digits, each with 7 segments and a decimal point
- Colon separator between digit 1 and digit 2
- 8 brightness levels controlled by software
- 2-wire interface supporting 3.3V and 5V logic
- Nonvolatile display memory
| Function | Pin |
|---|---|
| CLK | Clock signal input |
| DIO | Data input/output |
| VCC | Power supply (3.3V or 5V) |
| GND | Ground |
Connect CLK and DIO to any available digital pins on the Nano ESP32. The examples use D2 and D4.
Wiring Diagram
Connect the TM1637 module to the Arduino Nano ESP32:
- CLK to D9
- DIO to D10
- VCC to 3.3V
- GND to GND
This image is created using Fritzing. Click to enlarge image
Library Setup
- Plug the Arduino Nano ESP32 into your computer through its USB-C port.
- Open Arduino IDE. Pick Arduino Nano ESP32 from the board list and select the right port.
- Click the Libraries icon on the left sidebar.
- Type "DIYables_4Digit7Segment_TM1637" in the search field. Find the DIYables entry.
- Hit Install.
Self-contained library - nothing else to install.
Starter Sketch
The minimum code needed to get going with the DIYables_4Digit7Segment_TM1637 library:
#include <DIYables_4Digit7Segment_TM1637.h>
#define CLK_PIN D9
#define DIO_PIN D10
DIYables_4Digit7Segment_TM1637 display(CLK_PIN, DIO_PIN);
void setup() {
display.begin();
display.print(1234);
}
void loop() {
}
Create the display object with the pin numbers, call begin(), and start writing data. The Nano ESP32 uses Dx pin labels which map to the ESP32-S3 GPIO numbers internally.
Workshop - Display Integer Numbers
Put the display through its paces with various integer values - positive, negative, and zero-padded.
/*
* This Arduino Nano ESP32 code was developed by newbiely.com
*
* This Arduino Nano ESP32 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-tm1637-4-digit-7-segment-display
*/
/*
* DIYables_4Digit7Segment_TM1637 - Integer Example
*
* Displays various integer values on a 4-digit 7-segment display
* with TM1637 driver, including zero-padded numbers.
*
* Tutorial: https://diyables.io/products/4-digit-7-segment-display-led-tm1637-with-colon
*
* TESTED HARDWARE:
* - Arduino Uno R3
* - Arduino Uno R4 WiFi
* - Arduino Uno R4 Minima
* - Arduino Mega
* - Arduino Due
* - Arduino Giga
* - DIYables STEM V3: https://diyables.io/stem-v3
* - DIYables STEM V4 IoT: https://diyables.io/stem-v4-iot
* - DIYables STEM V4B IoT: https://diyables.io/stem-v4b-iot
* - DIYables STEM V4B Edu: https://diyables.io/stem-v4-edu
* - DIYables MEGA2560 R3: https://diyables.io/atmega2560-board
* - DIYables Nano R3: https://diyables.io/nano-board
* - DIYables ESP32 Board: https://diyables.io/esp32-board
* - DIYables ESP32 S3, Uno-form factor: https://diyables.io/esp32-s3-uno
* - It is expected to work with other boards
*/
#include <DIYables_4Digit7Segment_TM1637.h>
// Pin configuration - change to match your wiring
#define CLK_PIN D9
#define DIO_PIN D10
DIYables_4Digit7Segment_TM1637 display(CLK_PIN, DIO_PIN);
void setup() {
Serial.begin(9600);
display.begin();
Serial.println("TM1637 Integer Example");
}
void loop() {
// Display various integers
int numbers[] = {0, 42, 1234, -5, -123, 9999};
int count = sizeof(numbers) / sizeof(numbers[0]);
for (int i = 0; i < count; i++) {
display.print(numbers[i]);
Serial.print("Displaying: ");
Serial.println(numbers[i]);
delay(2000);
}
// Display with zero padding
display.print(42, true); // Shows "0042"
Serial.println("Displaying: 0042 (zero-padded)");
delay(2000);
}
Hands-On
- Wire the TM1637 module to the Nano ESP32 as shown in the wiring diagram.
- Connect the Nano ESP32 to your computer via USB-C.
- In Arduino IDE, choose the board and port, paste the code, and click Upload.
- Open the Serial Monitor to observe the results.
The display cycles through 0, 42, 1234, -5, -123, 9999, and then shows "0042" with zero-padding.
Method Reference
| Method | Action | Syntax |
|---|---|---|
| print(int) | Display an integer (-999 to 9999) | display.print(1234) |
| print(int, true) | Display with leading zeros | display.print(42, true) |
| clear() | Clear all digits | display.clear() |
Workshop - Display Text and Temperature
Put text strings and temperature readings on the display, including the degree symbol.
/*
* This Arduino Nano ESP32 code was developed by newbiely.com
*
* This Arduino Nano ESP32 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-tm1637-4-digit-7-segment-display
*/
/*
* DIYables_4Digit7Segment_TM1637 - TextAndDegree Example
*
* Displays text strings, special characters, and temperature
* on a 4-digit 7-segment display with TM1637 driver.
*
* Tutorial: https://diyables.io/products/4-digit-7-segment-display-led-tm1637-with-colon
*
* TESTED HARDWARE:
* - Arduino Uno R3
* - Arduino Uno R4 WiFi
* - Arduino Uno R4 Minima
* - Arduino Mega
* - Arduino Due
* - Arduino Giga
* - DIYables STEM V3: https://diyables.io/stem-v3
* - DIYables STEM V4 IoT: https://diyables.io/stem-v4-iot
* - DIYables STEM V4B IoT: https://diyables.io/stem-v4b-iot
* - DIYables STEM V4B Edu: https://diyables.io/stem-v4-edu
* - DIYables MEGA2560 R3: https://diyables.io/atmega2560-board
* - DIYables Nano R3: https://diyables.io/nano-board
* - DIYables ESP32 Board: https://diyables.io/esp32-board
* - DIYables ESP32 S3, Uno-form factor: https://diyables.io/esp32-s3-uno
* - It is expected to work with other boards
*/
#include <DIYables_4Digit7Segment_TM1637.h>
// Pin configuration - change to match your wiring
#define CLK_PIN D9
#define DIO_PIN D10
DIYables_4Digit7Segment_TM1637 display(CLK_PIN, DIO_PIN);
void setup() {
Serial.begin(9600);
display.begin();
Serial.println("TM1637 Text and Degree Example");
}
void loop() {
// Display text strings
const char* texts[] = {"HELP", "Hi", "COOL", "done"};
for (int i = 0; i < 4; i++) {
display.print(texts[i]);
Serial.print("Displaying: ");
Serial.println(texts[i]);
delay(2000);
}
// Display temperature with degree symbol
display.printTemperature(25, 'C'); // Shows "25°C"
Serial.println("Displaying: 25 degrees C");
delay(2000);
display.printTemperature(72, 'F'); // Shows "72°F"
Serial.println("Displaying: 72 degrees F");
delay(2000);
// Display string with degree constant
char buf[5];
buf[0] = '2';
buf[1] = '5';
buf[2] = DIYables_4Digit7Segment_TM1637::DEGREE;
buf[3] = 'C';
buf[4] = '\0';
display.print(buf); // Same as printTemperature(25, 'C')
Serial.println("Displaying: 25 degrees C (via print)");
delay(2000);
}
Hands-On
- Wire the module and upload the sketch.
- Open the Serial Monitor.
The display shows "HELP", "Hi", "COOL", "done", then "25°C" and "72°F".
Method Reference
| Method | Action | Syntax |
|---|---|---|
| print(const char*) | Display text (up to 4 chars) | display.print("HELP") |
| printTemperature(int, char) | Display temperature with degree/unit | display.printTemperature(25, 'C') |
| DEGREE | Degree symbol constant | display.DEGREE |
Workshop - Display Time with Blinking Colon
Set up a clock-style display with the colon blinking at 500ms intervals.
/*
* This Arduino Nano ESP32 code was developed by newbiely.com
*
* This Arduino Nano ESP32 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-tm1637-4-digit-7-segment-display
*/
/*
* DIYables_4Digit7Segment_TM1637 - Time Example
*
* Displays time in HH:MM format with blinking colon separator
* on a 4-digit 7-segment display with TM1637 driver.
*
* Tutorial: https://diyables.io/products/4-digit-7-segment-display-led-tm1637-with-colon
*
* TESTED HARDWARE:
* - Arduino Uno R3
* - Arduino Uno R4 WiFi
* - Arduino Uno R4 Minima
* - Arduino Mega
* - Arduino Due
* - Arduino Giga
* - DIYables STEM V3: https://diyables.io/stem-v3
* - DIYables STEM V4 IoT: https://diyables.io/stem-v4-iot
* - DIYables STEM V4B IoT: https://diyables.io/stem-v4b-iot
* - DIYables STEM V4B Edu: https://diyables.io/stem-v4-edu
* - DIYables MEGA2560 R3: https://diyables.io/atmega2560-board
* - DIYables Nano R3: https://diyables.io/nano-board
* - DIYables ESP32 Board: https://diyables.io/esp32-board
* - DIYables ESP32 S3, Uno-form factor: https://diyables.io/esp32-s3-uno
* - It is expected to work with other boards
*/
#include <DIYables_4Digit7Segment_TM1637.h>
// Pin configuration - change to match your wiring
#define CLK_PIN D9
#define DIO_PIN D10
DIYables_4Digit7Segment_TM1637 display(CLK_PIN, DIO_PIN);
int hours = 12;
int minutes = 30;
bool colonOn = true;
void setup() {
Serial.begin(9600);
display.begin();
Serial.println("TM1637 Time Example");
Serial.println("Displaying 12:30 with blinking colon");
}
void loop() {
display.printTime(hours, minutes, colonOn);
delay(500); // Toggle colon every 500ms for blinking effect
colonOn = !colonOn;
}
Hands-On
- Upload and watch "12:30" with the colon toggling on and off.
Method Reference
| Method | Action | Syntax | |
|---|---|---|---|
| printTime(int, int) | Display time HH | MM with colon | display.printTime(12, 30) |
| printTime(int, int, bool) | Display time, control colon state | display.printTime(12, 30, false) |
Workshop - Blink the Display
Create a blinking effect using off() and on() while keeping display content intact.
/*
* This Arduino Nano ESP32 code was developed by newbiely.com
*
* This Arduino Nano ESP32 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-tm1637-4-digit-7-segment-display
*/
/*
* DIYables_4Digit7Segment_TM1637 - Blink Example
*
* Blinks integer and text on a 4-digit 7-segment display
* using off() and on() to toggle the display.
*
* Tutorial: https://diyables.io/products/4-digit-7-segment-display-led-tm1637-with-colon
*
* TESTED HARDWARE:
* - Arduino Uno R3
* - Arduino Uno R4 WiFi
* - Arduino Uno R4 Minima
* - Arduino Mega
* - Arduino Due
* - Arduino Giga
* - DIYables STEM V3: https://diyables.io/stem-v3
* - DIYables STEM V4 IoT: https://diyables.io/stem-v4-iot
* - DIYables STEM V4B IoT: https://diyables.io/stem-v4b-iot
* - DIYables STEM V4B Edu: https://diyables.io/stem-v4-edu
* - DIYables MEGA2560 R3: https://diyables.io/atmega2560-board
* - DIYables Nano R3: https://diyables.io/nano-board
* - DIYables ESP32 Board: https://diyables.io/esp32-board
* - DIYables ESP32 S3, Uno-form factor: https://diyables.io/esp32-s3-uno
* - It is expected to work with other boards
*/
#include <DIYables_4Digit7Segment_TM1637.h>
// Pin configuration - change to match your wiring
#define CLK_PIN D9
#define DIO_PIN D10
DIYables_4Digit7Segment_TM1637 display(CLK_PIN, DIO_PIN);
void setup() {
Serial.begin(9600);
display.begin();
Serial.println("TM1637 Blink Example");
}
void loop() {
// Blink an integer
display.print(1234);
Serial.println("Blinking: 1234");
for (int i = 0; i < 5; i++) {
display.off();
delay(300);
display.on();
delay(300);
}
delay(1000);
// Blink text
display.print("HELP");
Serial.println("Blinking: HELP");
for (int i = 0; i < 5; i++) {
display.off();
delay(300);
display.on();
delay(300);
}
delay(1000);
}
Hands-On
- Upload the code. "1234" blinks five times, then "HELP" blinks five times.
Method Reference
| Method | Action | Syntax |
|---|---|---|
| off() | Turn display off (data preserved) | display.off() |
| on() | Turn display back on | display.on() |
| setBrightness(int) | Set brightness 0-7 | display.setBrightness(4) |
Workshop - Individual Digit Control
Set each digit position independently using numbers, characters, and the colon.
/*
* This Arduino Nano ESP32 code was developed by newbiely.com
*
* This Arduino Nano ESP32 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-tm1637-4-digit-7-segment-display
*/
/*
* DIYables_4Digit7Segment_TM1637 - IndividualDigits Example
*
* Sets individual digits, characters, and colon on a 4-digit
* 7-segment display with TM1637 driver.
*
* Tutorial: https://diyables.io/products/4-digit-7-segment-display-led-tm1637-with-colon
*
* TESTED HARDWARE:
* - Arduino Uno R3
* - Arduino Uno R4 WiFi
* - Arduino Uno R4 Minima
* - Arduino Mega
* - Arduino Due
* - Arduino Giga
* - DIYables STEM V3: https://diyables.io/stem-v3
* - DIYables STEM V4 IoT: https://diyables.io/stem-v4-iot
* - DIYables STEM V4B IoT: https://diyables.io/stem-v4b-iot
* - DIYables STEM V4B Edu: https://diyables.io/stem-v4-edu
* - DIYables MEGA2560 R3: https://diyables.io/atmega2560-board
* - DIYables Nano R3: https://diyables.io/nano-board
* - DIYables ESP32 Board: https://diyables.io/esp32-board
* - DIYables ESP32 S3, Uno-form factor: https://diyables.io/esp32-s3-uno
* - It is expected to work with other boards
*/
#include <DIYables_4Digit7Segment_TM1637.h>
// Pin configuration - change to match your wiring
#define CLK_PIN D9
#define DIO_PIN D10
DIYables_4Digit7Segment_TM1637 display(CLK_PIN, DIO_PIN);
void setup() {
Serial.begin(9600);
display.begin();
Serial.println("TM1637 Individual Digits Example");
}
void loop() {
// Set individual numbers on each digit position
display.clear();
display.setNumber(0, 1);
display.setNumber(1, 2);
display.setNumber(2, 3);
display.setNumber(3, 4);
Serial.println("Displaying: 1234");
delay(2000);
// Turn colon on
display.setColon(true);
Serial.println("Displaying: 12:34");
delay(2000);
// Turn colon off
display.setColon(false);
Serial.println("Displaying: 1234");
delay(2000);
// Set individual characters
display.clear();
display.setChar(0, 'H');
display.setChar(1, 'E');
display.setChar(2, 'L');
display.setChar(3, 'P');
Serial.println("Displaying: HELP");
delay(2000);
// Mix characters and numbers with colon
display.clear();
display.setChar(0, 'A');
display.setNumber(1, 3);
display.setChar(2, 'b');
display.setNumber(3, 7);
display.setColon(true);
Serial.println("Displaying: A3:b7");
delay(2000);
// Blinking colon effect
display.clear();
display.setNumber(0, 1);
display.setNumber(1, 2);
display.setNumber(2, 3);
display.setNumber(3, 0);
Serial.println("Blinking colon: 12:30");
for (int i = 0; i < 5; i++) {
display.setColon(true);
delay(500);
display.setColon(false);
delay(500);
}
delay(1000);
}
Hands-On
- Upload and observe the different digit and character combinations on the display.
Method Reference
| Method | Action | Syntax |
|---|---|---|
| setNumber(int, int) | Set digit 0-9 at position 0-3 | display.setNumber(0, 1) |
| setChar(int, char) | Set character at position 0-3 | display.setChar(0, 'H') |
| setColon(bool) | Control colon on/off | display.setColon(true) |
| setSegments(int, uint8_t) | Set raw segments at position 0-3 | display.setSegments(0, 0x76) |
Troubleshoot
| Issue | Possible Cause | Resolution |
|---|---|---|
| Display is blank | Wrong wiring or pin numbers | Verify CLK/DIO connections match code and VCC goes to 3.3V |
| Wrong characters | CLK and DIO swapped | Switch the two signal wires |
| Display too dim | Low brightness setting | Call setBrightness(7) for maximum |
| Library not found | Not installed | Install DIYables_4Digit7Segment_TM1637 from Library Manager |
| Upload fails | Board in wrong mode | Hold the BOOT button while pressing RESET, then retry upload |
Platform Support
The library is built entirely on Arduino standard APIs and supports all Arduino-compatible platforms (architectures=*).