TM1637 with Arduino Uno R3

Wiring for the TM1637 4-digit 7-segment display on the Arduino Uno R3 (ATmega328P, 5 V logic), chosen with the same pin rules BoardPilot uses: default buses first, and no pins that are used for flash, USB, the debugger or booting.

Wiring

TM1637 pin	Role	Arduino Uno R3 pin	Notes
CLK	Input to the part	2 (PD2)	Clock (not I2C, not SPI)
DIO	Input to the part	~3 (PD3)	Data (not I2C)
GND	Ground	GND
5V	Power	5V	Works at 3.3 V or 5 V

Check before you power it on

Supply: 5 V from the 5V pin.

Test code (Arduino)

// Library: TM1637 (Avishay Orpaz)
#include <TM1637Display.h>

TM1637Display display(2, 3);  // CLK, DIO

void setup() {
  display.setBrightness(4);
}

void loop() {
  display.showNumberDec(millis() / 1000);  // seconds since start
  delay(200);
}

Arduino board: arduino:avr:uno.

Questions

Which Arduino Uno R3 pins do I use for the TM1637?

CLK → 2 (PD2), DIO → ~3 (PD3), GND → GND, 5V → 5V.

Does the TM1637 work with the Arduino Uno R3 at 5 V?

Yes: the TM1637 runs at 3.3-5 V and the Arduino Uno R3 uses 5 V signals, so no level shifting is needed.

BoardPilot checks this wiring in 3D as you build it, and finds crossed or missing wires on the real board.

Download BoardPilot

Full Arduino Uno R3 pinout · TM1637 4-digit 7-segment display: all pins and data

The TM1637 on other boards

ESP32 DevKit Arduino Mega 2560 R3 Arduino Nano WeAct Black Pill STM32F411CE ESP32-C3-DevKitM-1 ESP32-S3-DevKitC-1 Nordic nRF52840 DK NUCLEO-F401RE Raspberry Pi Pico 2 Raspberry Pi Pico W Raspberry Pi Pico Teensy 4.1

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