tamilkamathaigal

Project Features Automatically resets a crashed, frozen Linux PC Simple Uses a cheap USB-to-serial adapter Introduction For several years I have been using a MythTV Linux server to record television shows. It works very well and I like it a lot. It has one major problem though: Sometimes it locks up. I suspect that this happens when it changes channels and signals are weak (e.g. due

Features Relatively easy to build Emulates a keyboard, so it needs no driver Costs around 10 € Is easy to configure, in under one minute Works with most remote controls Can easily be customised for other HTPC software Introduction I was always very fascinated with Objective Development's software implementation of a USB driver for Atmel controllers called V-USB. On their web site, they

Introduction Halloween is a rather new tradition in our part of the world, but my family is very enthusiastic about it. Tombstones are built, bones are scattered in our front garden and a fog machine is kept in the basement for just this one day of the year. This time I thought that I could contribute a little LED effect. My idea was to use a couple of red LEDs to create a red-glowing eye

Putting it all together In part 1 and part 2 of this posts I investigated and designed the components for a solar-powered Morse thermometer. In part 3 everything gets connected. In order to get the most out of the collected sunlight it is important to use as little power as possible. A red LED is a good choice here, because it only has a forward voltage of 1.7 Volts. So it will consume only

Setting Fuses As mentioned before, fuses are used to set a couple of things that might need to be set before the actual software starts to run. As a beginner you should not tinker with most of those settings, because it is possible to lock yourself out of in-system programming. The most dangerous fuse bits in that respect are SPIEN (SPI enable) for obvious reasons and RSTDISBL (reset

Installing the Software As mentioned, there are many options when it comes to software. One standard program, which is available for many operating systems is avrdude. Unfortunately, it is a command line tool, which makes it less than ideal for beginners. But there are GUI frontends available. I decided to use AVRDUDESS for this tutorial. And it is quite easy to use. But first,

What Hardware do I need? Obviously you need the controller. This can be any Atmel ATtiny or ATMega. You need a circuit board to put the controller in (the "target board") and you need an ISP programmer. Since ISP uses a serial format, the programmer can be rather compact. There is a wide variety of programmers on the market, from full featured expensive to cheap and simple. Since

Introduction Many of my projects use AVR controllers from Atmel. And they need to be "programmed". This means that the software needs to get written into their internal program memory. For beginners, this can be a major stumbling block in any project. And I do get lots of questions in connection with programming. So I decided to write this tutorial. But my intention is not just to

Several people asked me how you connect an ISP programmer to an ATMega8. It never occured to me that this could be a problem for anyone. But anyway, here is a schematic. Over time, I will write a tutorial on how to program AVR controllers. Please note that the header shows Atmel's standard pinout for the 10-pin ISP header. Most programmers use that same pinout. But to be safe you should check

Reverse Engineering a Solar Lamp Part 1 of this post is a write-up of my project for a thermometer with Morse code output. But I was not satisfied with the relatively high power consumption of the circuit, so I decided to use a solar cell to supply the circuit. A cheap source of solar cells these days are solar garden lamps. You get them for very little money in garden centres and DIY shops.

Project Features Extremely simple hardware Low-Cost Uses the internal temperature sensor of the ATtiny25 Introduction I used to have one of those electronic thermometers with an outdoor sensor. That sensor transmits its readings through an RF link. Except that it didn't really work. Every now and then I had to reset the thermometer so that it would re-connect to the sensor. This

Programming Software for the USBasp There are several interesting options, how to use the USBasp programmer. The LCSoft variant was sold with the option to download a program called ProgISP V1.72 from the vendors site. Also, a schematic was available as well as the drivers for Windows. Installation was no problem. I found no user manual in English, but usage of the software is fairly straight

Introduction When I started this blog I meant to do so mainly in order to document my own projects. I found that when I wanted to re-use parts of one of my projects I sometimes couldn't remember why I had made certain decisions. So I needed to document my work. And if anyone else could benefit from it, why not publish all in a blog? But I never intended to bore anybody with my opinions

The Micro POV was about making a really small POV display. I wanted it to be as small as I possibly could make it. And it is small. But when I wrote my post about it, a thought struck me: It can be even smaller. I had used a AVR tiny24 controller, which only has 14 pins. But I could also have used a tiny25, which only has 8 pins (including VCC, GND and reset) and still could control 8 LEDs. How

Electronics design in my opinion is the art of finding the best compromise. And this can be quite a complex art. There are many different and sometimes contradicting requirements to a project: Cost, time, space, weight, power, technology, market, availability of materials and tools, knowledge. This is why the all singing all dancing solution isn't always a good solution. Sometimes less is more.

Some time ago I stumbled over an article about charlieplexing on hackaday.com. Charlieplexing is basically a method to control n * (n-1) LEDs using only n I/O ports of a microcontroller. Say you have 5 I/O ports, then you can control 5 x 4 = 20 LEDs independently! Find more details in Wikipedia. I was fascinated, because I had never thought it was possible to control so many LEDs with so little