If you are more serious with embedded systems you probably are using JTAG debugger. If you decided to build an adapter, probably you should start looking for USB based JTAG adapter as COM ports are disappearing from computers.

This AVR JTAG interface uses specialized FT2232 chip with two independent channels where one is used for JTAG and another can be used for simple serial communication between target and PC. JTAG AVR adapter can run in two modes: The first mode allows run as independent software. There is support for connecting target via JTAG, read signature, reset target, download software (*.hex) into target and to manage target fuses (read, write); The second mode is AVRStudio mode. In this mode PC software interprets AVRStudio requests and communicate with target via JTAG. For AVRStudio it works as JTAGICEMK2 emulation.

Project is developed by David Cook, who decided to add two additional fans to its computer case that needs to be hidden in closed space where air doesn’t circulate very well.

Fan controller reads thermistor voltage drop via Attiny45 ADC channel and calculates environment temperature by using lookup table. Fans are controlled through two MOSFET transistors that are powered from 12V. As fan controller is inside computer case there is no need for additional power supply - it uses computer power supply. In order to avoid fans turning on and off at threshold level there is a 5 volt hysteresis programmed.

Author also has developed a professional version of dual fan controller with has 4x seven segment LED indication, three status LEDs, speaker for alarm. Professional version has many features like temperature reading, power voltage reading, motor current reading, screen saver, backing up settings in EEPROM memory. Check out the site for more details.

If you are PIC fan and looking for good development board take a look at this one.

It has a list of valuable features:

• PIC18F2550 MCU with external xtal;
• One channel 0-2.5V sigma-delta ADC converter;
• 6-channal 10-bit ADC 0-5V;
• Two connectors for text LCD or GLCD;
• USB port with type B connector;
• On-board low drop-out voltage regulator;
• rechargeable battery;
• 10-pin header for In Circuit Loader.

Board can serve as PIC learning platform or simply a base for final project. Personally me, I like that it has both connectors for text and graphical LCDs.

The idea of this universal IR remote transceiver (code name unzap) came from famous TV-B-Gone universal TV-off remote.

Remote control can be used to turn off any TV on your way. The board is small but includes an Atmega168, a USB port, a 2MB Atmel data flash (for storing all sorts of codes), a learning mechanism (which can detect the correct carrier frequency), four buttons (selecting transmitter and learning mode, enable USB, …) and four powerful IR LEDs.

This project is for those who want to control room light according to their mood. RGB mixing lamp is great in generating various colour schemes. It can work as stand alone device without PC connection.

It can be controlled remotely via standard RS485 bus system. RGB lamps are developed as stackable modules. If you want to build one - be prepared to develop four separate PCB’s for power supply, Atmega8 controller board, LED board and serial connectivity board. It has two firmware versions developed on ASM and C languages. Turn on deep blue colour and watch “The Abyss”.