[Nav] is working on a scratch-built wristwatch. Although it is based on an MSP430 microcontroller, it’s not the ready-to-hack ezCronos that you might be thinking of. Instead, [Nav] started with a different TI development tool that we’ve looked at before, the ez430-F2013.
The breakout board for the F2013 is small enough to meet his needs, but still provides easy soldering with 0.1″ vias that break out each pin. To make sure the timepiece is accurate he added a 32.768 kHz clock crystal. A small, square, LCD screen acts as the face of the watch, but we didn’t find specific part information for the display.
Currently the watch can run for a few days on the CR2032. We’d bet some work with sleep modes for the microcontroller can help with that. The watch has a couple of buttons that let you control it, and [Nav] discovered that he could fit everything into the watch case for an iPod nano. That’s creative!
We’ve seen other hacks with tiny batteries. The next logical step here would be to swap out the disposable coin cell for something that can be topped off with an external charger.
18 thoughts on “MSP430-based Wristwatch Project”
I really would like to know which screen he used. That is my biggest complaint with the Chronos is I wished it has a better screen. But I am thinking they chose that one for battery usage.
This just made me think how delightfully nerdy a Unix-time watch would be.
this post got me excited because
1) right off the bat i recognized the LCD as one that looks VERY similar to my pile of LCDs from Nokia 3587i cellphones that i had been wondering if anyone had a pinout for (too lazy to attach my logic analyzer between the cellphone and the LCD)
2) i have also been wanting to build a watch of my own
Depending on what voltage requirements there are for the setup it might be possible to simply swap out the CR2032 with a LIR2032, a lithium-ion battery the size of a CR2032, along with a mini USB socket & MAX1551 or similar lithium charging IC.
I did wonder where he got such a watch case to cram his setup into, that’s rather a neat idea using an iPod nano holder.
Have to say I’m feeling a little bad I haven’t done anything productive with my TI Chronos watch yet other than use it as a watch.
Yeah…mine is going to waste too…I was planning to use it to replace my car alarm clicker, but other things keep popping up. Plus, it is made in China…I don’t like developing for things made in China.
Really? I mean — really? You’d not develop software for a product because it was made in China? What DO you develop for, then? Last time I checked the majority of electronic products and components were produced in China, so you’d be at a loss there…
Arduino isn’t from china, neither is Teensy. It isn’t so much that it is made in china, but more because “Made in China” was in bigger letters than, “Texas Instruments”. On top of that, the watch cost $25 on sale…no chinese watch should be that expensive unless it has an apple logo on it.
The components for all of those products are still “Made in China.”
Hey, it’s a Nokia phone LCD. I’ve added the details to the blog post now.
I’ve been dying to build a watch, been seeing some custom home mades ones all over the place as of late.
I’ve thought about using a teensy or a programed ic or arduino..
I’ve also been thinking between using an lcd or leds.. graphical or binary
I’ve always wanted to make one of those. I think it’d be pretty wicked if you could get your hands on a small e-ink for super low power use, or an oled for tiny tetris (like when you are bored on the bus or in the can).
Also I’ve thought maybe a tiny solar panel on the inside (remove watch to charge) or an inductive charger would be nice for such a project.
Cool to see it actually built.
Agreed that an e-paper interface would be rad. E-ink sells a sample wristwatch for cheap:
I think the real question for Nav will be…. Can I play Doom on it?
Inductive charger isn’t hard.
I have at home one of those Wii Orb chargers, the coil and capacitor and small PCB inside the battery can be hacked into a micro assembly a fraction of the size :-)
I looked into salvaging e-ink from a broken Sony reader, unfortunately in order to fix it you need to remove ALL the moisture from the panel prior to fixing it down.
The plan here is to make a double sided PCB using the silver demister paint via trick (google it!) and as long as you are careful when peeling it off the backplane to keep the brown back contact in one piece it should still work.
Best bet for this appears to be the PRS500 and early 505’s, never had any luck peeling the ‘600.
DO NOT use chemicals, I learned that the hard way.
His battery problem is the choice of LCD. he needs to find a black and white transreflective LCD as they use 1/3 the power than the same type color LCD, some use even less by increasing the transition time of the LCD fluid. I.E. making the LCD too slow to display video. This makes it so you can pulse the lcd once every 5-10 ms to keeps the display visible but not power it 100% of the time.
also his choice of battery is far too small. he needs to get one of the bigger coin cells.
I personally would buy a Fossil MSN watch to hack for this project as you have a big chunky case already done, a B&W LCD and a battery+charging system all finished.
BLowing out the garbage Microsoft OS and code from a fossil watch would be a major upgrade.
You won’t win any fashion awards with that contraption strapped to your wrist.
e-ink would be a good idea. Can’t see any schematics. Source of FAM, is it built-in FRAM of MSP430xx?
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