This should be marked (2014) as the post is last updated April 24, 2014 (and (c) 2013). Would note that several of the links to components are dead, specifically the links to microduino.cc (check this link [1] and select the 3.3v/8mhz option) and radioshack.com (the link in the series is to the pre-petition website, try this link [2] for the motor but believe it's currently out of stock).
There's also http://www.ohwr.org/projects/f-watch/wiki, a smart watch made by a team at CERN for a retiring researcher. It's powered by a very low-power EFM32/ARM microcontroller, uses a metallic e-ink display, the board is designed with KiKad, and has all the resources they used on the website.
Better would be an e-ink display. OLED consumes too much battery. Using e-ink and writing power efficient code such a watch weeks or even months on battery.
It depends on your priorities. If you want a pretty display with lots of color, fast updates, and easy visibility in the dark, e-ink is out. All-day battery life is more than sufficient for many watch-wearers who aren't interested in sleeping with the thing on.
One of my favourite use cases for my Pebble Time requires wearing it whilst I'm asleep: I use it as an alarm clock. I'm awoken by it vibrating on my wrist. I find this a much more pleasant way to wake up than a normal audio based alarm. Being able to snooze an alarm without having to open my eyes or reach out of my warm bed and without waking my partner is brilliant. I would be annoyed by a watch which I had to remove each night to charge.
I've got an LG Urbane which I charge every morning while I'm showering and getting ready. It's on my wrist overnight for sleep tracking and the morning alarm. I can agree with your judgement on alarms, but my experience of an OLED-based watch differs from what you seem to expect :).
30 minutes is usually long enough, although I usually leave it longer than that because I'm still doing stuff. The last 5% charge is a lot slower, but isn't really necessary -- it doesn't matter if the battery drains from 95%--45% rather than 100%--50%.
Wow! You just made my weekend. Some projects take time and to see you do this from start to end is inspiring to me. I have some projects sitting for months and find it hard, sometimes, to just get them done.
"Build the hardware with 100% Arduino Compatibility"
That was his first mistake, :-) I like arduino for fast, quick and dirty stuff, but for a finished product, I'd rather try to do a closer to bare metal implementation. But otherwise, very cool project.
It's not a mistake, it's a feature! 100% Arduino compatibility can make things much more approachable for casual enthusiasts.
I've seen some non-programmer _artists_ get Arduino stuff working---barely---which is awesome! If they'd had to start by figuring out how to get a cross-compiler working (especially on Windows), they'd probably have given up.
Well, this was your first mistake :-) One of the pictures [0] in his series clearly shows that this is not a finished product. This is definitely a side/weekend project.
Yep. Bare metal refers to your code accessing the silicon without the help of other drivers or an OS. You write the code to directly access the IO pins that drives the LCD or LEDs or to read the buttons, or other on board circuitry.
Thanks for sharing this. I am thinking about creating a smartwatch. A nicely built smartwatch can replace smartphone. Instead of building the parts ourselves would not it be better to import parts?
[1] https://www.microduino.cc/product/core-copy
[2] https://www.radioshack.com/products/radioshack-3vdc-micro-vi...