Summary of Building a SmartWatch
This article details the author's journey to build a custom smartwatch, aiming to blend technology with personal style. The project involves designing and prototyping using specific electronics tools and components. The author discusses initial design choices, including the selection of a breakout board and display, as well as challenges faced during the first prototype iteration, such as missing connections and incorrect footprints.
Parts used in the Custom SmartWatch:
- Stellaris Breakout Board
- DesignSpark software
- EAGLE software
- Color OLED display
- SD Card
- Joystick button combo
- Power supply for OLED display
- Seeed Studios PCB fabrication
I have an issue with smart-watches. Watches in general fall into one of two categories: a tool to tell the time, or a fashion statement. Increasingly, I believe the latter category is larger than the first. With the advent of the iWatch, Pebble and the like, fashion and making a statement has moved into technology. It’s not quite a new thing but nevertheless, it’s something I’m not too fond of. My solution? Make your own smartwatch.
There is a precedent for this. Steve Wozniack sports a pretty fly nixie tube watch. It’s pretty cool, but also a statement of sorts too. I believe there is quite an underground scene of custom electronics watches. I’ve been meaning to up my game with electronics anyway, so I’ve been working on a few initial prototypes.
I use DesignSpark on the recommendation of a sparky friend of mine who has a successful business building bespoke electronics. I have a Stellaris Breakout Board – the same board used in the cubesats – that I figure I can use for development. Most of the parts I’ve ordered from R.S Components though that might change in the future. I’ve previously used EAGLE, which I’d also recommend.
I decided the first stage would be to build a breakout-board with the easy components attached. This includes a display, an SD Card, a small joystick button combo and a power supply for the OLED display. I’ve decided to go with a colour screen, the same used in the tricorder project, as it’s fairly cheap and works with an SPI interface. The SD card also has a straight forward interface, so I figured the only tricky part was the power supply.
The first board was a little large and sadly, didn’t work. I’d missed out a logic high line into the OLED driver chip. These boards I had made at seeed studios who you may remember I tried to visit on our recent trip across Russia and China. Sadly, the day we turned up in Shenzen was a Chinese public holiday. Oh well. The eagle-eyed amongst you will notice the wire I’ve hastily added in order to test whether or not I could save the board. Apparently not. In addition, the footprint for the SD Card reader wasn’t quite right, so that also needed adjustment.
Read more: Building a SmartWatch
- Why did the author decide to build their own smartwatch?
The author believes modern watches are increasingly fashion statements rather than tools and wanted to create a unique electronic device. - What software is recommended for designing the circuit?
DesignSpark is used based on a friend's recommendation, while EAGLE is also suggested as a previous experience. - Which microcontroller board was selected for development?
A Stellaris Breakout Board, which is also used in cubesats, was chosen for the project. - Where were the printed circuit boards manufactured?
The boards were made at Seeed Studios, although the visit there coincided with a Chinese public holiday. - What type of screen interface does the project utilize?
The project uses a color screen that works with an SPI interface. - What specific error caused the first board to fail?
The first board failed because a logic high line was missed into the OLED driver chip. - Did the SD card reader function correctly on the first attempt?
No, the footprint for the SD Card reader was not quite right and required adjustment. - What inspired the underground scene of custom electronics watches mentioned?
Steve Wozniack's nixie tube watch is cited as a precedent for custom electronic timepieces.
