Introducing the DICE CLOCK, shown here displaying the time in several different modes.
The time is displayed as pips on a dice; a pair of which are used for hours, minutes and optionally, seconds.
Simple, elegant, cheap and, above all, HACKABLE!
If you’ve been following some of my most recent posts (and I hope you have!) you will have seen several different clock designs. While they are quire different, they share several things in common – namely being built on an Arduino platform, incorporating a DS3231 Real Time Clock (with battery backup) and driving some number of addressable LEDs.
While I have built prototypes using the UNO, Nano and Pro Mini Arduino boards, I needed a more cost-effective solution. I designed a PCB to take an Atmega328 and its associated components, the RTC module and a 6-pin header for a removable FTDI USB interface module (only required to download software). While this is a very simple design I added headers for all analog and digital pins. I created the schematic and PCB routing using the free Fritzing software. The software is pretty intuitive and comes with a large library of pre-defined components, although I did find it challenging to create and edit new components. Nevertheless, I’ll use it again and recommend it to others.
I read a message on a local bulletin board that mentioned Dirty Boards, a Hong-Kong based low-cost, no-frills PCB manufacturer. I uploaded the boards’ design files (more on that later) and 3 weeks later (and $24 lighter) I received 12 (not the 10 promised) boards. Excellent!
Of all of the clocks that I’ve designed and made, the WORD CLOCK is by far the one that gets the most attention.
While the original design had a complex arrangement of an LED driver board and many (one for each word) custom LED boards, I decided to simplify the design and use hybrid driver/ RGB LED “strips”.These LED strips (cut into strips for a total of 118 LEDs) are housed on the face-side of a double-sided enclosure made out of copper-clad laminate (see below). The face-side contains the LED strips and the baffles to cut out light bleed from one word to the next, while the back-side is used to house the electronics and power connections.
Over the past couple of months I have been playing with a Bluetooth module that I purchased some time ago from eBay. I purchased the small 3.3V Bluetooth module and a carrier interface (with level shifters) to make it easier to use on a breadboard and interface to the 5V Arduino boards.
After soldering the units together, rather than just play with the unit, I started to mess with the AT-command interface and appear to have set it to some weird and unresponsive state. Finally, my patience got the better of me and I put it aside.
Last night, I decided to play with it again and got it working, sending data to and receiving data from an Arduino Nano. Bing! A light went off. I would use Bluetooth to allow me to use my Android cell phone to control all of the functions of my wall clock, including setting its time. Yeah, baby!