Oscilloscope is one of most expensive tool electronics hobbyists must have in order to successfully put their designs to work. It’s like an eyes to see what’s really going on electronics circuits. But can everyone afford to buy one? So this simple scope project can be a temporary solution while sewing for a real one. It is based on Atmel Tiny45 microcontroller and have two 0-5 V analog inputs. Input can be scaled down with the trim pot.

Input pins are soldered on a side so that scope could easily be used in a breadboard. Microcontroller reads data and sends it via USB port to PC. Computer recognizes scope as a HID device, so it doesn’t require any drivers, the only thing you need is to have .NET framework to run front end program.

So if you need to do some low speed testing – this tool might be right choice to start.

RFID technology have successfully spread in the industry. So RFID tags are a juicy bite for most embedded developers and hobbyists. So why not to build a RFID tag emulator that could be connected to computer.

This RFID tag emulator simulates a standard 125kHz EM4001 compatible RFID tags. Emulator microcontroller simply receives ID from computer program via RS232 port and emulates it. All you need to connect an antenna coil and start talking to RFID readers. I smell some sort of RFID hacking here!

Ok maybe this isn’t a real solar light as it comes from LED, but the idea is laudable. Idea is pretty simple and not new – harvest solar energy during day and store it in to battery and deliver light to plant during night. In fact there are some difficulties in doing that. Author have used a Luxeon K2 LED that requires over 2,79V, while two NiCad batteries can give around 2V.

After some experiments he changed battery to Li-Mh with 3.7V and built an ATTiny15 microcontroller based circuit where LED is controlled by PWM depending on how much energy is left on battery. Battery voltage is measured via MCU ADC channel and depending on voltage level PWM signal is adjusted. This is more fun project to work with as practically LED light cannot replace sunlight.

Some embedded projects look really crazy and fun. And even these can have a practical issues. This is one of Cornell University students project where they put acceleration sensor on a foot to measure its acceleration during walking, running and sport activities. They used a Kionic KXSD9-2050 three-axis accelerometer, XBee wireless transmitter, and an ATmega324P microcontroller. So transmitter sends measured acceleration data along with time values where it can be viewed in Matlab.

As a result they’ve been able to send x,y, and z acceleration values and display it on Matlab graphs. When you have data in your computer this is up to you what analysis are you going to do in order to emit indicators showing where sportsman had too strong football kick what means injure risks or other effects. Accelerometers on a shoe or hand can be used for more exiting purposes like perfecting arm motion in bowling, baseball etc. Anyway this is a great project where you can get some skills in wireless data transmission, acquiring data from accelerometer and interfacing microcontroller to Matlab via RS232 interface.

Are you a fan of digital photo frames where you can put your favourite photos and and take them where ever you want? Probably this is even cooler if you could store photos in your hand made digital photo frame. This would definitely amaze your friends.

This particular DIY photo frame has some really nice features including that project is based on AVR microcontroller with rather small program size, It uses quite large “240×320” QVGA TFT display BL-TFT240320PLUS that is capable to reflect 16 bit colour. Photos are stored in SD card. Probably the only downside is that photo frame can only understand BMP files. Anyway the idea were to keep it simple, keep it small and fast.