Watch

Binary Watch Project

Welcome to the Binary Watch project! This repository contains all the files related to the design and development of binary watches using STM32 and ATMega328p microcontrollers. A blog post detailing this can be found at https://divija.info/

Project Overview

The Binary Watch is designed to display the time in a "binary but base 10 format". This means each digit of the time in base 10 format is displayed in binary on an LED matrix.

For example, 17:15 is expressed on the LED matrix as:

0 0 1 0 1 0 1 0 0 1 1 1 1

where 1 = LED ON and 0 = LED OFF

Repository Structure

watch_STM32

This directory contains the design and firmware for the STM32-based binary watch.

watch_ATMega328p

This directory contains the design for the ATMega328p-based binary watch.

The firmware from the STM32 version can be modified to work for this hardware. Use the arduino versions of all the libraries and an RTC library for the DS3231 RTC chip

Setting the Time

• When the code is uploaded for the first time, the RTC time is set to the compile time.
• The current time is displayed on the LED matrix in binary format.
• Everytime you reset or change the battery, the time is set to midnight. This choice is purely aesthetic; I would prefer that my watch always resets to a defined time instead of a random compile time everytime setup() runs. This is achieved by storing a flag in the EEPROM.

Contributing

Contributions are welcome! I'm still struggling with getting the external oscillator to work with my setup. I think the issue is with my choice of extenal capacitors - they should be 15pF instead of 1pF. The RTC section of the code works perfectly fine on an external Nucleo board, so I think it is a hardware issue. If you have any suggestions or improvements, please open an issue or submit a pull request.