Space Invaders LED Matrix Clock

Inspired by GeckoDiode (Instructables) and smooth_jamie (Instructables), I had to take up the challenge and build a version of my own.

Case design is original and is designed to work with a MAX7219 LED dot matrix module. Arduino sketch is based off smooth_jamie original work. I improved the RTC logic and fixed various LED hex byte arrays for minutes and animations that did not display correctly. In addition, the Alien Space Ship now completes the cast of characters.

LED Matrix Editor is a great tool to help create and troubleshoot matrix displays.

PARTS:
Arduino Nano Amazon
MAX7219 LED Matrix Display (Red and Green LEDS) Amazon - Green Amazon - Red
DS1307 Tiny RTC Module * REQUIRES PCB MODIFICATION * Amazon
CR2032 Lithium Battery
8 ohm speaker Amazon
1K ohm Resistor
SPST Momentary Push Button Amazon
SB400 Solderable PC BreadBoard Amazon
Micro USB Interface Power Adapter Board 5V Breakout Module Amazon
5 VDC Source - I used a USB power supply for a cell phone
#4-20 X 5/8" Plastic Screws, QTY 4 Amazon

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Arduino Sketch - Included in Thing Files
SpaceInvadersClockRepRapTodd03152020.pdf
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Note: Tiny RTC module needs R4, R5, R6 and D1 removed from PCB. R6 requires a wire to complete the circuit after removing the resistor. Now that the faulty recharging circuit is disabled, use a standard lithium 2032 battery to keep time when power is removed.

Arduino libraries required:
MaxMatrix - interfaces with the series of 8X8 LED displays
JeeLabs RTClib - Real Time Clock - DS1307 Tiny RTC Module

UPDATE: 03152020 - Fixed sketch to display midnight correctly. Updated line #1205 - case 12: case 24: to case 12: case 0:, now correctly evaluates time at midnight. Thing file updated with code fix.

UPDATE: 10162024 - Substitute DS1307 Tiny RTC Module with DS3231 RTC Module for greater time accuracy