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Bedside MP3 Alarm Letter Clock

For this project I wanted to make a convenient and fully functional bedside alarm word clock.

My personal prerequisites for a bedside alarm clock are:

Readable at any light, while not blinding at night
MP3 alarm tunes
Attractive and small form factor
Snooze function
Memory function, so that time, alarm time, ringtone and volume are not lost anytime the power is cut off.
Birthday function: At my birthday (and those of my family members) I want to get awakened by “happy birthday” rather than the standard ringtone
I could not find any instructable combining all of these; hence this instructable.

The clock is build around a 8X8 WS2812B Matrix. Because of the low amount of LED’s, not all words can be made up of consecutive letters. Most 8x8 word clocks (like this nice one) solve this by grouping more letters over a single LED, though others have more creative solutions. I decided to go for a solution more like this one, where words are made from non-consecutive letters. This gives it some magical twist, as you do not see the words before they are lit. To increase readability, letters from the same word share the same color. It’s a bit puzzling to read at first, but after a while you can read it in a blast. This is also why I call it a letter clock rather than a word clock. The clock wakes me up every morning and I’m still amazed by how the words are formed!

Apart from the electronics, almost all components are reused or reclaimed items that I already had at home. The only tool you really need and probably do not have at hand for the clockface is a laser cutter. Luckily there are many fablabs and makerspaces that can help you with that. Thank you Makerspace De Prins!

Electronic components:

8X8 WS2812B LED matrix
Arduino nano
DS3231 real time clock module
DFPlayer mini
micro SD card to put in the DFPlayer mini (smallest/cheapest you can find will do the job fine)
A photo diode
1000 F capacitator
a speaker as small as possible
generic wires, connectors, resistors, buttons
Some wood, MDF,.. for the box”

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