Print PDF
Favorite
Email
**************************************************************************
Major updates - A much better enclosure for this clock has been designed - check out
http://www.instructables.com/id/The-Wordclock-Grew-Up/
**************************************************************************
Last month I wanted to build a special gift for my beautiful wife, Megan. She has a teaching background in English, so what better present to make for her than a clock that uses language to tell the time for her desk at work.
The original project that I created used a Microchip PIC microcontroller (16F877), because that's what I had in the garage. Since I published it (http://www.instructables.com/id/A-Word-Clock/), quite a few people, including my next door neighbor (Thanks Mikal) have asked me why I didn't use an Arduino. Having never used one, my automatic reaction to Mikal was 'Whats a one of those??" So, I did some research and found out what an Arduino was. Wow - they are so cool - so simple to develop for, and the barrier to entry is so low!. I ordered one from eBay, and re-designed the clock to use the Arduino Duemilanove as the controller.
I have to admit right from the start that the Arduino is a beautifully engineered piece of work - While I am used to the PICs, because I have been playing with them for years, I do admit that there is a certain level of 'unreachability' for the beginner because of the requirement that specialised programmers be purchased or built. The Arduino is equally powerful, comes on it's own little self contained board, and best of all is self programmable using a USB cable.
So, here it is - The word clock - constructed using an Arduino!
I am now able to sell all sorts of components, ranging from complete clocks, through to kits, through to individual modules and components. Please visit my web site www.dougswordclock.com for further information.
Major updates - A much better enclosure for this clock has been designed - check out
http://www.instructables.com/id/The-Wordclock-Grew-Up/
**************************************************************************
Last month I wanted to build a special gift for my beautiful wife, Megan. She has a teaching background in English, so what better present to make for her than a clock that uses language to tell the time for her desk at work.
THE BACKGROUND
The original project that I created used a Microchip PIC microcontroller (16F877), because that's what I had in the garage. Since I published it (http://www.instructables.com/id/A-Word-Clock/), quite a few people, including my next door neighbor (Thanks Mikal) have asked me why I didn't use an Arduino. Having never used one, my automatic reaction to Mikal was 'Whats a one of those??" So, I did some research and found out what an Arduino was. Wow - they are so cool - so simple to develop for, and the barrier to entry is so low!. I ordered one from eBay, and re-designed the clock to use the Arduino Duemilanove as the controller.I have to admit right from the start that the Arduino is a beautifully engineered piece of work - While I am used to the PICs, because I have been playing with them for years, I do admit that there is a certain level of 'unreachability' for the beginner because of the requirement that specialised programmers be purchased or built. The Arduino is equally powerful, comes on it's own little self contained board, and best of all is self programmable using a USB cable.
POWER
I have also listened to people who have constructed the original clock, and done away with the need to run off AC power. This clock simply uses a DC supply of 12 Volts, so you can run it off a wall wart, or off a set of batteries. If you are using batteries, may I suggest 'D' cells, as they run forever, or a couple of 6V 'Lantern' batteries.REUSE YOUR ARDUINO FOR ANOTHER PROJECT
Finally, I have designed the controller board so that you can construct the project with your Arduino Duemilanove board just by plugging it in. But, if you want to recover your Arduino for something else, you can install the optional support components along with an appropriately programmed ATMega168 and a handful of support components and your project will still operate. People on eBay will sell you a ATMega168 with a boot loader that you can simply pop back into your Arduino board.So, here it is - The word clock - constructed using an Arduino!
I am now able to sell all sorts of components, ranging from complete clocks, through to kits, through to individual modules and components. Please visit my web site www.dougswordclock.com for further information.
Remove these ads by
Signing UpStep 1The new hardware - Controller board schematic
BETTER DRIVERS
My original clock used discrete transistors to drive the array of LEDs. I have realised that while that approach works fine for a project that I have built for myself, it makes it more complex for others to build, so this new clock uses ULN2003A Driver ICs. The ULN2003A contains a set of darlington transistors in a convenient DIP package, so there is MUCH less soldering to do.A NEW PCB
I have also re-designed the PCB to make construction much simpler - The Arduino controller simply plugs into the new PCB. If you want, once you have constructed the clock, you can recover your Arduino board by purchasing an ATMega168 with a boot loader, and populate the PCB with just the new Microcontroller and a crystal.IS THIS JUST A NEW SHIELD?
In the spirit of Arduino development, it would be fair to say that the controller board was a 24 output LED (or relay) driver shield. It is just as happy to turn on a big set of 24, 12 volt relay coils as it is turning on a bank of LEDs.Below you will find the new schematic diagram for the controller board as a PDF file.
Note that you should look at step 4 to understand what resistors to use. Don't simply use 360R and 36R with supply voltages above 10v. You will need to use 680R and 270R instead.
WordClock-Arduino-Schematic-V1.0.pdf(595x842) 64 KB| « Previous Step | Download PDFView All Steps | Next Step » |
The design has changed quite a bit since this initial project, and I also have a board that I have been selling via my web site for $25.
There are plenty in stock, and it is the same board that I use for my complete clock and kits :-) Here is the link to it:
http://www.dougswordclock.com/components.html
What will you make and show for us to see?
Doug
The 9v was a reference to the original, which needed 9V AC, which after rectification acme out to about 12V DC.
I am sorry for the confusion.
Could you post a clearer pdf of the V2 schematic. The schematic included in the assembly manual is too fuzzy to be able to read it.
Thanks
i would implement the dcf77 receiver module for automatic upgrade time but i have a problem to write the code, you help me ?
sorry for my english!
Based on this project, I ordered a professional double-sided board (111x60 mm) that you can easily sold all the necessary for this project, including a standalone Arduino. On request I can send with a small fee the gerber files. For further questions write me.
Thanks
i like it, do you have the plan to compose the reader to this board ?
Have a look at http://www.dougswordclock.com to see how it has expanded.
I can provide you with a plan for the current PCB, or if you like, I am happy to send you a kit for either a full clock, or just a controller.
Doug
the article which i wanted to reply is your another article called "A Universal RFID Key".
i clicked many articles and opend many windows, and i replied the wrong one ^_^
Don't worry, I live in fear of when I order 100 of the for the kits that I make up, that I will make the same mistake.
Doug
If you have a septic system, do not dispose of this in the drain. Septic systems rely on a complex bacterial process that this will disrupt.
Here in Australia, we have plastic / clay pipes for the drainage, and by the time 250mL of used etchant has been diluted with 10L of rinsing water, there isn't a major hastle - especially as it gets further diluted by other waste streams as it traverses the sewerage network.
Remember that Hydrochloric Acit is used in swimming pools to alter the PH of the water, so once it is diluted it isn't a big problem.
The complexity hapens when you are dealiing with commercial quantities - most governments have rules about disposing of 50L of waste products like this.
any advantage of using separate shift register and driver chips?
why not just use something like the Philips 4794 which has a built-in shift register?
I'm currently building the Arduino version and wanted to know if it is possible to add 4 more LEDs for minutes 1 to 4. I see you've done this for the PIC version, but I'm afraid I know nothing about the Arduino yet.
What is the purpose of the electrolytic capacitors (C4, C5, C6) on the main DC line before and after the voltage regulator? Is it to keep a constant +9, +5 DC voltage? Why not use resistors?
Thankx!
You can certainly use wider cable and reduce the number of connections.
Your quick reply is much appreciated!
you may like to consider using 680 ohm and 360 Ohm resistors with a 12Volt supply - the more recent clocks that I provide kits for use these values, and they are beautifully bright. - Just substitute 360R for the 36R and 680R for the 360R - overall they reduce the current appplied.