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 ‘microcontroller’
Roll Your Own Electronic Lock
Thursday, June 25th, 2009Controlling the Brightness of an LED (Using PWM)
Monday, June 22nd, 2009It is easy to use a microcontroller to turn LEDs on and off in almost any pattern you want. (Click here for more information.) But you can only turn the LED on and off. So what if you want to control the brightness of the LED? The same problem comes up in robotics where you want to control the speed of a motor with a microcontroller. It is not good enough to just turn the motor on and off. To control the brightness of the LED or speed of the motor you have to control the amount of current going through the device. But how? One solution that may occur to you is to quickly turn the LED or motor on and off. The current only flows when the output is low (for microcontrollers LED circuits are usually wired so current flows into the microcontroller when the output is low, as shown in the tutorial at http://www.iguanalabs.com/1st2051.htm). The output of your microcontroller will look like the following square wave. (more…)
Conventional Microcontrollers
Friday, December 26th, 2008Instructions Set of the MCS-51
Wednesday, December 24th, 2008All instructions of the mcs-51 microcontroller are shown on 79 pages.
For example the instruction JB bit,rel:
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Flash Microcontrollers
Tuesday, October 28th, 2008The Prog-Studio 6 Software
Tuesday, October 7th, 2008Aside from basic functions such as the reading, programming, comparison copying and erasure of chips in the Batronix programming devices, the Prog-Studio 6 software offers numerous other functions. The Hex/ASCII editor gives you many options for working with the component contents, and the MC editor integrates a comprehensive compiler/assembler/debugger for developers of microcontroller applications. (more…)
8051 C-Compiler uC51 Software
Tuesday, October 7th, 2008The µC/51 compiler is well known for it’s high quality and high density code. You can develop high quality software for any 8051 in ANSI C. µC/51 comes with an incredible optimizing compiler, you can even write software in ANSI C on 8051′s with 1kB of code memory! µC/51 is absolutely complete: user friendly multi file editor, compiler, assembler, downloader, source level debugger. It’s a complete toolchain – You won’t need anything else.
USBasp – 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…)