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This instructable will show you how to make your own arduino based watch that tells time using a matrix of LEDs. This is my first instructable, so if something is unclear leave me a comment or send a message!
I was inspired by all the cool LED watches that I saw on this website:
http://www.tokyoflash.com/en/watches/1/
They have a lot of different designs that let you tell the time in very unique ways. So, I thought I'd try my hand at making my own LED watch using an arduino.
My watch design is very basic, but can be easily modified to create different LED layouts and different programming schemes. I am fairly new to arduino programming so for this instructable I will be using a modified code that I got from the Makerbot Watch project:
http://wiki.makerbot.com/makerbot-watch
I had big issues with the battery life of my first watch design, but with the modified Makerbot code and a larger battery, the watch will tell the time for at least 12 hours on a single charge. I am working on modifying the code to allow the watch to only display the time when you press one of the buttons. This should greatly increase the battery life. I will post it as soon as its finished.
***EPILOG CHALLENGE***************************************
I have entered this Instructable into the Epilog Laser Cutter challenge. The laser cutter would come in handy when designing new watch faces and enclosures. The watch faces could be etched/cut with numbers or words to make telling the time much easier. Not to mention greatly improving the aesthetics. Also, the time it would take to make the watch enclosure would be greatly reduced, the dimensions would be more precise, and it would open up possibilities to use different materials. Overall, I would use the laser cutter to make a wide range of higher quality LED/Arduino watches.
*******************************************************************
NOTE:
This instructable requires the soldering of very small surface mount components. If you are new to soldering, or have never handled surface mount parts before, I will try to explain as best I can how to successfully solder this project together.
I was inspired by all the cool LED watches that I saw on this website:
http://www.tokyoflash.com/en/watches/1/
They have a lot of different designs that let you tell the time in very unique ways. So, I thought I'd try my hand at making my own LED watch using an arduino.
My watch design is very basic, but can be easily modified to create different LED layouts and different programming schemes. I am fairly new to arduino programming so for this instructable I will be using a modified code that I got from the Makerbot Watch project:
http://wiki.makerbot.com/makerbot-watch
I had big issues with the battery life of my first watch design, but with the modified Makerbot code and a larger battery, the watch will tell the time for at least 12 hours on a single charge. I am working on modifying the code to allow the watch to only display the time when you press one of the buttons. This should greatly increase the battery life. I will post it as soon as its finished.
***EPILOG CHALLENGE***************************************
I have entered this Instructable into the Epilog Laser Cutter challenge. The laser cutter would come in handy when designing new watch faces and enclosures. The watch faces could be etched/cut with numbers or words to make telling the time much easier. Not to mention greatly improving the aesthetics. Also, the time it would take to make the watch enclosure would be greatly reduced, the dimensions would be more precise, and it would open up possibilities to use different materials. Overall, I would use the laser cutter to make a wide range of higher quality LED/Arduino watches.
*******************************************************************
NOTE:
This instructable requires the soldering of very small surface mount components. If you are new to soldering, or have never handled surface mount parts before, I will try to explain as best I can how to successfully solder this project together.
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Signing UpStep 1LED Matrix
This watch will tell time using a total of 28 (output) LEDs, and be controlled by 3 (input) tact switches. Obviously, an ATmega328p does not have that many programmable I/O pins so some manipulation needs to be done to individually control all those LEDs. The buttons will be controlled by 3 individual pins.
To do this, we will use a technique called charlieplexing, or display multiplexing. Basically, this method will allow us to use X number of pins to control X*(X-1) number of LEDs. For example, we can control 6 LEDs with only 3 output pins. This is possible by utilizing the tri-state logic properties of microcontrollers and the forward bias of LEDs. In other words, each pin can be set in 1 of 3 states: High (5 or 3.3V), Low (GND), or Not Connected (a high impedance state that disconnects the pin from the circuit). Also, an LED will only light up and pass current to the rest of the circuit in one direction (from anode to cathode). The first four images will give an example of how charlieplexing works using 3 pins and 6 LED's.
Now, by expanding this basic layout we can create a matrix of 28 LED's that can be controlled by a total of 11 output pins.
This is a relatively simple explanation of a complex process. If you would like more information, I found this instructable to be more comprehensive, and very well written.
To do this, we will use a technique called charlieplexing, or display multiplexing. Basically, this method will allow us to use X number of pins to control X*(X-1) number of LEDs. For example, we can control 6 LEDs with only 3 output pins. This is possible by utilizing the tri-state logic properties of microcontrollers and the forward bias of LEDs. In other words, each pin can be set in 1 of 3 states: High (5 or 3.3V), Low (GND), or Not Connected (a high impedance state that disconnects the pin from the circuit). Also, an LED will only light up and pass current to the rest of the circuit in one direction (from anode to cathode). The first four images will give an example of how charlieplexing works using 3 pins and 6 LED's.
Now, by expanding this basic layout we can create a matrix of 28 LED's that can be controlled by a total of 11 output pins.
This is a relatively simple explanation of a complex process. If you would like more information, I found this instructable to be more comprehensive, and very well written.
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http://www.sparkfun.com/tutorials/109
they have the same file and a really good tutorial on how to install it.
I can't really give you a .zip file to send to seeedstudio because you first need to place an order with them for the boards then place your order number on the board's silk screen layer. So if I made the gerbers here for download, they would be missing the order numbers. Sorry about that
That's a big problem to me.So ,how can I fix this problem?!
Thanks!
Once you fix this error, you may also get an error when the compiler reaches the "boolean" line. To fix this, you need to download the arduino Frequency Timer 2 library. I've used this library on past projects so I forgot to mention it in the instructable. I will add it soon, but you can google it if you want.
Let me know if this works. And thanks for the comment, I would love to see how your watch turns out. Please post some pics!
I'll show you some pics later!What's your mail?What's your name?Where are you from?I just want to be a good friend with you!
I from HongKong! My name is Lawrence!
If you look through my instructable, you'll see that I made the case piece by piece. But, I'm basically just making a box. So if you can find a plastic or metal box that can house the PCB (and still looks good to be on your wrist) you can just cut the holes for the buttons and watch band. Then, glue a piece of clear acrylic as the box top so you can see the LEDs. That's just one idea...
Fab.
Way beyond my skill level.
looking at the band glue joint in the photo, it just doesn't look very strong to me and i don't know if the circuitry could take the drop if the band broke..
I wonder if keeping the band as one piece that either ran thru the watch or below it, with the watch being rivited thru the back, would hold up a little better?
would take some thought to deal with any clearance issues but it may be worth the effort since its clear you have plans to get this into production?
just a thought.
really nice work.
you've got my vote.
The glue joint that I describe for the band has been working out pretty well so far. I have been wearing my watch mostly everyday for weeks now and so far so good. But you're right, the joint could eventually wear out. I'm playing around with different options. I was thinking of splitting the end of the strap inside the case and then gluing the flaps to the inner wall. Or, maybe crimping something to the end (like a staple) so that it can't be pulled out. These could work, but I am open to any ideas....
Freakin' awesome instructable. Excellent details.
I have a half done design for an arduino watch with EXACTLY the same layout of hour LEDs, but your overall design incorporating the LiPo charger is just so much better overall I'm going to just stop working on mine and use yours - thanks for posting the design files!
Anyone interested in a group buy? I don't really need 10 copies...