A simple clock with a virtual RTC, based on:

• 1 x Arduino Nano
• 4 x MAX7219 8x8 Led Matrix
• 1 x Resistor Light Dependent (optional)
• 1 x passive Buzzer or Speaker (optional)

RLD and Buzzer are optional. A base to learn or to build.

This is not so far original, we can find already so many sketch for a clock.

It is using the library <LEDMatrixDriver.hpp> by Bartosz Bielawski. This library is using SPI hardward and a buffer, that displays data fast as lightnings. (https://github.com/bartoszbielawski/LEDMatrixDriver)

It is displaying digits with sliding effect and many options can be set, like design, font types...

A DS3231 RTC module can be added easily, to preserve time/date settings and to have accurate calendar.

TODO

• chronometer
• a RLD (Resistor Light Dependent)
• settings management, for alarms too
• music for the alarm (hope to manage 2 voices for pretty sound)