Electronic security locks, popularly known as “dongles,†are commonly used to deter software piracy. This idea describes a simple yet-powerful design of such a security lock using the linear feedback shift register (LFSR) principle. The lock, which is implemented using Atmel’s AT90S2323 AVR RISC microcontroller, connects to the PC’s RS-232 serial port. The lock uses the PC’s serial port to communicate to the PC, as well as derive power for its own operation. Commercially available dongles come in various shapes and connectivity. The most common type connects to the PC’s parallel port. Increasingly, dongles with USB connectivity also are appearing, and those using RS-232 connections exist as well.
Posts Tagged ‘avr’
Roll Your Own Electronic Lock
Thursday, June 25th, 2009USBasp – USB programmer for Atmel AVR controllers
Monday, October 6th, 2008USBasp is a USB in-circuit programmer for Atmel AVR controllers. It simply consists of an ATMega8 and a couple of passive components. The programmer uses a firmware-only USB driver, no special USB controller is needed. (more…)