If you are a fan of AVR and you need to disable RESET pin and use it as regular pin you will need a High-Voltage programmer of AVR microcontrollers.HVProg is a nice High-Voltage parallel programmer.It is a redesign of the original STK500 without all components of a development board. It is based on the original ATMEL schematics that are freely available on the net (i.e at avrfreaks.net). The main target was to keep all nessecary functionality to programm all available AVR controllers in every programming mode that the STK500 supports.
HVProg-High-Voltage programmer for AVR: [Via] - [Link]
PINs, passwords, secure entry systems; just about everything you access these days needs some form of passive authentication code. Heck, even that Wi-Fi router in your basement uses a mega 63-character password for enabling secure access. Before you know it, you’ll even need a password just to go to bed at night.
Portable Password Generator: [Link]
The design is based around the AVR Butterfly from Atmel. The use of this module greatly simplifies the hardware design and constrution and packs plenty of punch for $19.99 USD. The remaining hardware can be easily placed on a single sided PCB ($10-$20). The MP3 decoding is handled by a VS1001K decoder chip from VLSI Solution Oy ($20). This chip also has an onboard DAC with enough power to drive headphones, simplifying the board design even further.
AVR butterfly Mp3: a diy mp3 player: [Link]
you should also check the DIY Mp3 player article i wrote some time ago.
ATMEL Microcontrollers can be programmed with ISP(In-System Programming) which helps to develop your applications because you don’t need to insert/remove the microcontroller. This is an ISP module for ATMEL Microcontroller that supports ISP such AT89SXXXX, AVR families etc. It Requires no power supply because it uses power supply from target board. This circuit needs only 10 resistors, 1 IC, 1 Capacitor,1 R-Pack.PCB size 1.6 X 4.1 cm. and Plated-Through-Hole type.
ATMEL ISP Module: [Link]
The counter contains only three inexpensive ICs (well, add a regulator and three transistors), and operates from 6 - 15V DC at about 25mA. The most expensive single item is the LCD display, which is an industry standard 16 x 2 dot matrix module, which can often be found used or at bargain prices. This isn’t a kitset, but the parts are easily obtained, and the circuit can be built using any prototyping technique, or you could design your own PCB. The prototype was built on a small commercial strip board.
AVR Frequency Counter: [Link]