ESP8266 based small NTP clock

Features

• 24 hour time display
• NTP sync
• DST support (automatic change)
• Configurable over WiFiManager softAP config
• OTA upgradable firmware

Prerequisites

• ESP8266 board (recommended: NodeMCU/compatible see BOM)
• TM1637 4 digit 7 segment display
• PlatformIO

Build & Installation HOWTO

Hardware BOM

• NodeMCU v3 board
• TM1637 4 digit 7 segment display with colon
• Female-female dupont cable 4pcs (usually comes with the display)

Wiring between NodeMCU and TM1637 display board

NodeMCU 3.3V -> Display Vcc
NodeMCU GND  -> Display GND
NodeMCU D3   -> Display CLK
NodeMCU D4   -> Display DIO

Software installation

• Download and install PlatformIO
• Optionally read https://docs.platformio.org/en/latest/quickstart.html

PlatformIO automatically downloads all required libraries, boards, and configures your environment.

Uploading

PlatformIO serial

platformio run --target upload

PlatformIO OTA

platformio run -t upload --upload-port <IP address of ESP>

WiFi Configuration

If unable to connect to a known WiFi AP, the unit will come up in configuration mode. Connect your PC/smartphone to SSID “clockAP” and follow captive portal UI to configure your WiFi credentials. Upon successful connnection to your WiFi, clock will remember credentials.

Future plans

• Force configuration mode (button/jumper, etc)
• Openweathermap (?)

Special thanks

• William Moeur for NTP code improvements and credentials config