Completely open source watch with tons of features

There are lots of DIY watch projects on the internet. Some of them are great, some of them lack to feel of finished product. If you looking something like this check out at F*watch project which open source and built by using free tools. It was developed at CERN as a gift for retiring colleague. It has everything you would expect on modern digital watch. It has been stuffed with bunch of sensors including GPS, Pressure sensor, accelerometer, compass, ambient light sensor. Watch has 128×128 LCD display with back-light, micro USB connector, four push buttons buzzer, vibrating motor, and microSD memory card. It is powered by 500mAh Lithium-ion battery. To make it all possible, schematic was designed on four layer PCB with KiCad. Case was 3D printed out of resin. Plans were developed with open FreeCAD design tools. Clock is ticking around ARM Coretex-M3 microcontroller from SiLabs Giant Gecko featuring 128KB RAM and 1MB of Flash. Watch software runs a FreeRTOS operating system. Watch is fully functioning already, but seems that team are open for bug reports and feature request. Continue reading

Programming STM32 USART using GCC tools. Part 1

When we need some feedback from the microcontroller, usually we use USART. It allows to output messages, debug information to the terminal screen. Also, data can be sent to MCU same way. For this purpose, STM32 microcontrollers have more than one USART interface allowing to have multiple streams of data output and input. USART interface is designed to be very versatile, allowing to have lots of modes including LIN, IrDA, Smart card emulation, DMA based transmissions. But for now, let’s focus on standard USART communications we could send and receive messages from the terminal window. Continue reading

STM32F100RB based sunrise alarm clock will wake you up rain or shine

Alarm clocks usually – ring a pair of bells, play jarring noise, imitate the cock a doodle do of a rooster what else? We have seen alarm clocks with radios, and Phones with alarm clocks but most of them [if not all] uses sound to wake you up – not really the most gentle way of waking someone up. What do we recommend? The sunrise clock – instead of breaking your morning with a bunch of rings that also scares away a good start for your day this clock illuminates the surroundings giving a feel of morning sunrise in the comfort of your own room [yeap rain or shine]. Its build is quite straight forward – time was kept using a real time clock implemented using a STM32F100RB Arm Cortex M3 processor and a ceramic oscillator. Time is displayed using a pair of 8×8 LED matrices. The lamp [the source of light] is controlled using a dimmer circuit composed of an opto-diac and a triac – the opto – diac isolates the microcontroller from the high voltage AC source needed… Continue reading

How small quadrocopter can be?

Arnaud Taffanel, Tobias Antonsson, and Marcus Eliasson have been working on amazing project – a miniature quadrocopter. Its size is as small as 8 cm and weights 20 grams. It uses a PCB as main frame and place for solid electronics like ARM Cortex -M3, couple gyros, 3 axis accelerometer and 2.4GHz radio module. Quadrocopter is powered with 110mAh LiPo battery that came from RC plane. This gives about 4.5 min flight time. Continue reading

Monitor temperature on your web page with ThingSpeak

This project is build around mbed platform which features LPC1768 ARM Cortex M3 microcontroller. IT reads temperature from DS1620 IC. mbed reads correct time values via Network Time Protocol (NTP) and then logs temperature values to ThingSpeak. ThingSpeak is a great and open application platform that allows users to upload various data by using a web service. It already provides a nice chart API that can be embedded in to your web page for real time data visualization. Check out for more ways to send data to ThingSpeak. Continue reading

Guitar effects shield for Maple

Maple is a STM32 ARM Cortex-M3 processor based development system that is compatible to standard Arduino shields. Using Maple board is really handy when more processing power is needed like for simple Audio effects. In this project there is a real-time audio processing implemented with help of guitar effect shield. Maple board gives a maximum 11.8 bit resolution to do real time 20kHz sampling which is quite enough to do awesome stuff with signals. The actual shield contains input and output low-pass filters and variable gain amplifier. So connect input to guitar and output to headphones or further amplifier and enjoy the play. Continue reading