DTMF extension for microcontroller system

Telephone lines that maybe found in your house may be used not only for making calls but also for other purpose like home automation, remote device control. To make it possible there is an interface between phone line and microcontroller system needed. This DTMF extension is universal module that can be connected to any microcontroller platform. It detects DTMF tones and decodes them to binary digits that can be easily read by microcontroller, which can decide what tasks to perform. DTMF decoder is based on CM8888 chip which is ideal for interfacing with MCU. Here is an example source code for interfacing with AVR ATmega8535 microcontroller which is written for WinAVR compiler toolset. Continue reading

Tiny pocket password reminder

Probably everyone has a long list of passwords to remember. But are they safe from other and from forgetting them. Some people are using same password for all cases…well this is not safe. And of course using popular words as passwords also isn’t safe. It is better to use characters mixed with numbers. But these are hard to remember.   Alberto ricci bitti have built a fancy embedded pocket password reminder which can remember hundreds of passwords. The circuit is simple – menu navigation is done with encoder rotor and single button. Information from Cypress CY8C27443 microcontroller is displayed on 2×16 character LCD display. In order to access passwords you need to enter 5 digit code by rotating and selecting symbols with rotor encoder. But the most interesting thing in… Continue reading

Proteus projects and tutorials

Today you don’t have to mess with wires in order to program and run microcontroller programs. There are so many tools that allow you to develop complete projects, simulate and debug them like they are real world examples. smainj in his French page has compiled ad nice collection of Proteus projects mostly for PIC microcontrollers.   His projects include positioneer, simple security system, data acquisition system with 16 analog and 16 digital inputs. But most exciting thing is that he publishes nice tutorials on how to set up embedded projects on Proteus Design Suite. Video projects include: -Designing a Schema Using ISIS; -Using mikroC compiler to Write a program for PIC16F; -Simulating programs; -Converting circuit to PCB; -Sending information from Computer to LCD Using virtual USART communication; -Software development :… Continue reading