This is a LED clock project using Arduino-compatible ESP8266 and LED driver TM1637. I've been using this clock for several years, and it continues to run. I'm satisfied with it. Despite its cheap ...

Countdown timer with LED display drive by TM1637 and Arduino Nano. - StoicaT/Timer-with-TM1637-and-Arduino ...

TM1637 data transfer carries with answering signal ACK. For a right data transfer, an answering signal ACK is generated inside the chip to lower the DIO pin at the failing edge of the eighth clock.