How to make a very slim watch and keep battery life long? In this Hack-a-Gecko project, they tried to catch two birds with one stone.
We thought it would be cool to utilize the extremely low power EFM32 in combination with an extremely low power display to create a wrist watch demo application. And usually, the smaller and thinner something is, the cooler it is. (Admittedly, wrist watches do not necessarily follow this trend… big watches.)
Anyway, we wanted it slim. The starting point was the memory LCD display from Sharp (link). It is truly a Nano ampere display technology. And it is also thin, only 0.75 mm. A watch also needs a battery, cool new technologies exist such as the Thinergy battery, but the voltage of 4.1 V is a bit awkward. We decided to use a standard 3.0V CR1616 cell as it can power the EFM32 and display directly. Thickness of battery + display is 2.35 mm, is it possible to design the electronics as well within this thickness limit…? Challenge accepted!“
“ The Pocket Mini Computer was designed by Jeff Ledger.
The Pocket Mini Computer is pre-installed with a COLOR BASIC. COLOR BASIC is similar to the BASIC found on common microcomputers of the 80’s and early 90’s.
Explore micro computing with a machine which: Can be successfully assembled in an evening. Can be programmed in BASIC. (and other languages) Can play games and run programs. Most importantly: Can be understood.
The Pocket Mini Computer Kit arrives as a project which requires a small amount of soldering, all components are „thru-hole“ making it an easy project for anyone with modest soldering skills.
„Smartphones are equipped with dizzying array of wireless communication capabilities. Some of these features just go totally unnoticed. One such wireless communication protocol is called ANT+. A friend of mine wanted to make a working prototype of an idea he had using ANT+ technology. While there are other mcu’s (read atmega/arduino) already had some libraries and code written for communicating against ANT+, it wasn’t enough for me.
Most of the existing code only worked as a slave, where it just tried to receive data sent by Garmin Heart Strap.
This slave implementation was only on either arduino or PC (python and C)
What I was more interested in was to leverage the ANT+ radio to not just receive data, but also send data. I wanted the mcu to interact with the world and use ANT+ to transmit data to my cellphone, for example.“
That’s cool, on http://blog.section9.co.uk/2010/03/iphone-rfid-reader.html you can see the work process in pictures. The RFID chip is from http://www.id-innovations.com/new%20launch.htm.
„The idea behind this project is to see what the iPhone’s serial is capable of and to try and have a little fun with RFID along the way. This reader works with the low frequency (125Khz) tags but I have a half working version for MiFARE Hi-Frequency as well.“
For just $49 you can start with mobile development. And yes the watch shows the time out of the box.
The eZ430-Chronos is a highly integrated, wireless development system based for the CC430 in a sports watch. It may be used as a reference platform for watch systems, a personal display for personal area networks, or as a wireless sensor node for remote data collection.
Based on the CC430F6137<1 GHz RF SoC, the eZ430-Chronos is a complete CC430-based development system contained in a watch. This tool features a 96 segment LCD display and provides an integrated pressure sensor and 3-axis accelerometer for motion sensitive control. The integrated wireless feature allows the Chronos to act as a central hub for nearby wireless sensors such as pedometers and heart rate monitors. The eZ430-Chronos offers temperatureand battery voltage measurement and is complete with a USB-based CC1111 wireless interface to a PC.
The eZ430-Chronos watch may be disassembled to be reprogrammed with a custom application and includes an eZ430 USB programming interface.
eZ430-Chronos wireless watch
eZ430 USB programming and debugging interface
CC1111 USB RF access point
Mini Phillips screwdriver
CD containing documentation and development software“
„This article shows how to build a small, cheap and simple frequency meter, without any fancy, out of reach components. The simple proposed design can measure frequencies up to 40 Mhz with errors below 1%! This degree of precision will be more than enough to debug most of your analog and digital circuits, and will give you the ability to analyze many aspects that you were unable to see before.“