HAPPY NEW YEAR

HAPPY NEW YEAR

2010

AVR Temperature Meter

This is a four-channel temperature measurmet adapter that works without external power supply. It will suitable for measureing temperature and logging its data with a PC. The circuit diagram is very simple and no adjustment is required, everybody will able to build it with ease. These great project created by ChaN.

"I chose an Atmel ATtiny15L for this project. It is the only device that has a built-in 10bit A-D converter in the 8 pin AVRs. The A-D converter has a bandgap reference and differencial amplifire as its front-end. The AVR core is clocked by only internal RC oscillator (calibrated to 1.6MHz), any other clock souce cannot be used. Also 25.6MHz clock source that 16x multiplied from core clock is available for timer/counter. This means that a fast PWM output can be generated. Therefore the ATtiny15L has good analog I/O capabiltity.

In this project, the A-D converter is used as four channels, single-ended, no gain and VREF from Vcc configuration. However RSTDISBL fuse must be programmed in order to use pin #1 as one of the analog inputs, an AVR programmer that can program in HVS mode is required."

For documentation, schematic dan code, download here

[link]

Simple Metronome Project

Daniel designs this Metronome with a few simple electronic components.The Metronome is any device that produces a regulated audible and/or visual pulse, usually used to establish a steady beat, or tempo, measured in beats-per-minute (BPM) for the performance of musical compositions. It is an invaluable practice tool for musicians that goes back hundreds of years.

Material Needed:

1. 555 IC
2. 3x 1K Ohm Resistor
3. 2x 22uF 16V Capacitor
4. 9V Battery
5. 8 Ohms Speaker
6. 250K Ohms Potentiometer

[link]

How to Record Video Using VLC in Ubuntu / Debian

VLC can also used for recording videos during Playback. But, By default the record button is hidden in VLC. First you have to enable the Record Button.


How to Enable Record Button in VLC

Select     View->Advanced Control.

The record button will now appear.
Now You can Record movies and videos by clicking on the button dering playback

Clicking again in record button will stop recording.

I have tested it in VLC 1.0.3

Multifunction Digital Thermometer

This instructable will show you how to create a multifunction platform with a thermometer, chronograph (count up timer), count down timer, and light display. It is also intended to be a platform for other analog sensors or any other functions you can think of. Project is based on Atmega168 microcontroller. Information is displayed on dual 7 segment LED display.

Multifunction Digital Thermometer [link]

Serial interfacing LCD with PIC Microcontroller

Parallel interfacing LCD with MCU at least need 6 I/O pins (4 bit mode) and maximun can up to 11 I/O pins (8 bit mode). The I/O pin can be cut down to 3 pin by serial iterfacing using shift register. They were few shift register can be used such as 74HC164, 74HC595, CD4094 and any compatible 8 bit shift register. Before you attempt to do serial interfacing, it is good pratice to familiar with parallel interfacing. You can find many reference from internet.Following diagram show the serial interfacing Hitachi compatible 2 X 16 LCD modules with Pic16F84 or Pic16F628 MCU.

Download documentation and source code for serial interfacing LCD with PIC here (zip file)
[link]

How to Install HP Printers in Ubuntu / Debian /Fedora / Suse Linux Using HPLIP

Hewlett-Packard's Linux Imaging and Printing software (HPLIP) is used for driving HP Printers and Scanners in Linux. HPLIP software which supports 1,952 HP printers. Most of the Linux Distributions includes  HPLIP.Only need to upgrade.

Latest Version HPLIP 3.9.2 supports - OpenSuse 11.2, Fedora 12, Debian 5.0.3

• Printing support for HP printers including: Deskjet, Officejet, Photosmart, PSC, Business Inkjet and LaserJet.
• Color and monochrome scanning from compatible Officejet, PSC, Photosmart, and LaserJet MFPs.
• USB, network, and parallel connection types.
  

Official Site

Installation

First You have to download HPLIP Form Here

Now you can install / Upgrade using automatic Installer


Linux distributions supported by the automatic installer:

• SUSE Linux (10.3, 11.0, 11, 11.1, 11.2)
• Fedora (9, 9.0, 10, 10.0, 11.0, 11, 12, 12.0)
• Ubuntu (8.04, 8.04.1, 8.04.2, 8.10, 9.04, 9.10)
• Debian (5.0, 5.0.1, 5.0.2, 5.0.3, lenny, lenny/sid, stable, testing)

Now Download file to any folder

open a terminal and type

$sh hplip-3.9.x.run

If the installation shows any error, there may be some missing packages, then you have to install the missing dependencies and retry the installation again.

More installation help

Atmega168 RDS decoder

This decoder is fed by a RDS demodulator IC (or tuner) which has RDDA (data signal) and RDCL (clock signal) outputs.The microcontrolller is an Atmega168 clocked on the external 4.332MHz crystal from the RDS demodulator. TDA7330B RDS demodulator IC from STMicroelectronics to be used in this project. The TDA7330B is connected to the Atmega168 with RDDA connected to PD4 (on PORTD) and RDCL to INT0 (PD2).


The software in the Atmega168 is able to decode the following RDS data:

* Programme Identification code (PI: 0x83C7, Detected new station.)
* Program service name (PS: RADIO538)
* Programme Type code (PTY: 0x0A, Pop Music.)
* Traffic Programme Identification code & Traffic announcement code (TP&TA: 0x01 0x00, Traffic announcements available on this station and maybe via EON on another station.)
* Music Speech switch code (MS: 0x01, Music is being broadcasted or station does not use MS flag.)
* Decoder-identification control code (DI: 0x01, Stereo, Dynamic PTY.)
* Alternative frequency codes (AF: 0x98, 102.7MHz.)
* Linkage Actuator (LA: 0x00)
* Extended Country Code (ECC: 0xE3)
* RadioText (RTA: Radio 538 = Randstad (Zuid) 102.7 FM)
* Clock-time and date (CT: 0x1A53CD844, UTC 2006-07-02 (MJD 53918) 13:33:00 +02:00, TIME 15:33:00)

Download for document, source code here (zip)
[link]

Serial Port IR Receiver Using AVR

Another cool microcontroller project created by Klaus Stock. He said, this is a simple IR receiver circuit which plugs into a serial port of a computer. This circuit has two major advantages:

1. it uses an Atmel AVR RISC microcontroller (an AT90S2313) instead of the usual PIC microcontroller and
2. it uses a Maxim MAX232 for the generation of valid RS232 levels.

Advantage 1 is, of course, only valid for all those AVR addicts which have this device (and the corresponding programmer) ready at hand and don't care about PICs and PIC programmers. Advantage 2 comes into play if the IR receiver has to placed at a great distance from the computer; the MAX232 is more likely to deliver valid signals over bigger distances than cheaper solutions.

[Link]

How to Rip DVD using VLC Player

If you have VLC player, no need of other DVD ripping Software.
It includes a basic ripping facility. 

Select 
Media menu -->Convert/Save--> Disc tab.

• You can adjust the Starting Position and choose  only specific titles or chapters.
• Enter file name with  .MPG, and start ripping.
• Click Save.

How to Setup "Windows" Button in Ubuntu Linux

You can see a Windows button ( button with Windows Emblem and placed between Ctr; & Alt) in the Keyboard. This Tip will help you to utilize that key for opening your Ubuntu Menu in a single touch.

Open a Terminal and Type the following

$ gconftool-2 --set /apps/metacity/global_keybindings/panel_main_menu --type string "Super_L"

Digital Clock with PIC16F84A

This is a small ajustable clock based on microcontroller PIC16F84A microchip.The electronic project here is very simple because the hardware only uses 74hct238 demultiplexer, 4x7 segments, and some resistors. The software is programmed through a device connected to serial port with icprog and made/debuged with MPlab. For PIC Programmer you can use JDM PIC16F84A programmer.

[link]

AVR Infrared Link Project

This AVR microcontroller project created by Sivan Toledo. In this project he created an infrared (IR) link that provides bi-directional communication between the NXT and the new Power-Functions system, which consists of a battery box, motors, a remote control (an IR transmitter) and an IR receiver that controls the motors.

He previously built an IR transmitter for the NXT which used an MSP430 microcontroller and which was able to send Sony IR commands. In this project, he wanted to achieve three additional goals:

• To analyse the Power-Functions IR protocol.
• To build a system that could not only send IR commands, but could also receive and decode them.
• To experiment with AVR's, another family of microcontrollers.

But for this project he tried to use AVR Microcontroller. Compared to the MSP430 microcontrollers, the AVR family offers many more chips in DIP packages, they run at wider supply voltages (most can tolerate at least 2.7-5.5V and some operate down to 1.8V), and their pins can supply a lot of current (up to 40mA for a single pin). The wide range of supply voltages means that they can be connected to the 4.3V supply of the NXT's ports directly without a regulator, and the ability of the pins to supply a lot of current simplifies some circuits, such as when the chip needs to drive a bipolar transistor or a LED. Another advantage of the AVR is that they can be programmed using a wide variety of simple circuits, not just with proprietary programming devices.

[Link]

USB AVR Programmer STK500

In this microcontroller project, Guido Socher design a state of the art USB programmer for the AVR microcontrollers from Atmel. The programmer firmware has no device dependent data. Therefore it works for almost any AVR microcontroller on the market and possible future microcontrollers.

This USB programmer has, unlike other programmers, no "chicken and egg problem". That is: you can build it from scratch without the need of another programmer to load the initial firmware.The firmware is open source and programmed in C according to the AVR068 specification from Atmel.

[link]

Scroller 7 × 5 LEDs based on Attiny2313

Cool microcontroller project from kalinda. In this project he used microcontroller AVR Attiny2313 that is perfect for controlling the 13 pins required for the matrix of LEDs. he has also provided pins in the most optimal order to occupy as little as possible.

List of materials

• Programmer for AVR micros (AVRisp MKUII in my case)
• Microcontroller Attiny2313 with fuses configured for internal oscillator 8Mhz
• 1x Display 5 × 7 leds Kingbright
• 1x voltage regulator 7805
• 1x battery or source of food 9v
• 2x Capacitors 100uF
• 2x Capacitors 100nF
• 5x Resistances 90 Ohms

Required Software

• Kalanda Led Composer to generate animations.
• WinAVR and AVR Studio to compile the source.
• Source code firmware for Attiny2313

Drawings and plates

• Outline and plate format Eagle
• PDF plate positive or negative plate
  
• PDF side components
  
• PDF scheme

[link]

DivX Converter for Ubuntu / Debian Linux :

Convert Your files to DivX on Ubuntu / Debian using  Simple utility DivX Converter. DivX converter is a simple Mencoder GUI to Make Video  with subtitle attach for your  DivX Player . It support Copy AVI  , HDTV, NTSC and PAL format . 

List Of Feature :

1. Easy GUI

2. Convert variety type of video format to avi LIKE : ra;ram;rm;rmvb;moov;mov;qt;mqv;ogg;ogv;m4v;dv;dif;wmv;wma;

wm;asf;ass;wvx;wmx;wax;asx;mpe;mpeg;mpg;m1s;m1v;m1a;m75;m15;mp2;

mpm;mpv;mpa;3gp;3gpp;avi;vfw;avi;sdv;dat;flv

3. Has many different filters to convert to LIKE : High Quality DivX , HDTV , NTSC , PAL and Custom AVI filters.

4. You can merge your subtitle to your favorite video, with many encoding support .

How To install

Download Deb File ( DivX Converter 2.0 Beta) from here

Dependency :

mencoder libfribidi0

If you have any Problem Download the dependency file libfribidi from here

LCD SWR Meter using PIC 16F88

Measuring SWR at VHF/UHF frequency was never a fun. Most radio amateurs just assume that their 50 ohms cable is matching a beam or GP.

LCD SWR Meter presented here meet many simple task using a microcontroller PIC16F88. The very basic purpose to make this project is to encourage radio amateurs to build their own High Quality LCD SWR Meter at low price, instead of buying expensive ready made units.

[link]

Measuring Heart Rate on LCD using PIC

Did you know that The human heart can be measured optically. The heart beat with the varying blood pressure leads to a measurable change in the visual content of peripheral blood vessels. This is as good at the finger detect. There are two project work available, which were so far advanced that the optical signal pulse seized on a liquid crystal display graphically. Both works have been with a microcontroller PIC16C74 to collect and visualization of the signals.

Pulse measurement in a light
The light source was a red LED superhelle. The finger penetrating light was a light-frequency converter TSL230 detected. The period of the signal from the TSL230 was using the capture of the micro-controller unit with an accuracy of about 15-bit recorded. Through digital filtering 50Hz interfering signals were suppressed and the pulse signal extracted.

Pulse measurement in reflection
For the lighting of the skin's surface, an infrared LED used. the censor use PIN photodiode. With an analog circuit filters were equal light and high frequency interference signals eliminated. The signal was pulse by the A / D converter of the microcontroller with 8-bit digitized.

[Link]

MJoy- USB video game controller

This microcontrller project build using micrcontroller AT mega 8 and Xtal 12 MHz as the clock source.
"If you like to play video games in your computer as much as I do, you probably already heard about the MJoy, which is an USB joystick made by Mindaugas that uses an ATmega8 and have 24 buttons, one hatswitch (or POV or D-Pad depending on the game) and 6 analog axes." said Raijuu.

More information about this microcontroller project check the source here.

LM75 Temperature Sensor with 7 segment display output

This is a test project built hastily on a solderless breadboard. It uses a LM75 to read the current temperature via I2C and displays the result on three 7 segment displays. It uses a PIC16F628 with an internal 4 Mhz clock. The program was created using JAL

[link source]

Howto Convert Ext3 filesystem to Ext4 Filesystem without Reinstalling OS in Ubuntu

You can convert your existing Ext3 filesystem to Ext4 with an easy procedure.

Things to remember

• Unmount the filesystem before convert
• Filesystem must be non-root

This way you can improve the performance, storage limits and features of your existing filesystem without reformatting and/or reinstalling your OS and softwares.

First, unmount the partition: umount /dev/sda2 (change sda2 with your Drive)

Next, run a filesystem check on it to make sure it is in sane condition.

fsck.ext3 -pf /dev/sda2

Enable new features of ext4 on the filesystem

tune2fs -O extents,uninit_bg,dir_index  /dev/sda2

Run a filesystem check. to make sure that the filesystem is now clean.

fsck -pf /dev/sda2

Now edit your /etc/fstab file and replace "ext3" with "ext4" for /dev/sda1. Other options may differ for your system.

/dev/sda2  /disk ext4 defaults 0 2

Try to mount your new ext4 filesystem: mount /disk

AVR Internet communications device

If you looking for Microcontroller project that controlled via internet protocol, well this project could be your reference to build it. Internet0 is a electronic project by Neil Gershenfield, Raffi Krikorian and Dany Cohen. The concept is a new network of physical objectsthat are IP enabled. Any items we use in everyday life would have the ability to communicate in IP, and thus send data over the internet in a standardized manner, without considerable electronics or cost.

This microcontroller project using AVR ATmega8 programmed ini C. For display they use LCD HD44780.

The main elements of the project are:

Transmission
to send a UDP internet0 protocol. Implementation:
o A circuit board with a Tiny15
o Assembly code to send the protocol
o Lines for power and signal
o An LED to troubleshooting and to indicate transmission

Reception
Translate the clicks to bits

PC Communication:
A program in Python that receives information from the serial port and transmit this into the internet

Read more

USB AVR Programmer

Serasidis says "Nowadays, USB is the most popular connection connection between PC and peripherals such as AVR programmers, printers, scanners etc. For that reason I had to modify my old serial AVR In-System-Programmer (ISP) to work with USB connection. You can say, "use a USB to Serial adaptor to connect your AVR ISP with your PC". Yes, that could be a solution but it would cost me more money than a singe FT232BM chip because I had to include an USB to RS232 adaptor and a power supply for my programmer. (almost €30)".

So, the solution was to replace the two transistors, that were used to adapt the RS-232 voltage levels to TTL voltage levels, with a USB to RS-232 chip such as FT-232BM.

This programmer worked perfect with AVRprog (zip file) but it could work with AvrOspII V5.47 also.

Download the source code, firmware, programming software, schematic and PCB for this programmer here
[source]

Small TV Terminal AVR Project

When you use microcontrollers in your designs, sometime you face a problem how to show user required data. Several LEDs, 7 segment display or LCD module can be solution. But if you must show a lot of information simultaneously, it can be difficulty. Large LCD modules are expensive and graphic modules require complicated control. You can solve it with a help of PC. Just send data via serial line to the computer and display everything on computer's display said Vassilis Serasidis.

This project created by Stan Pechal and he using AVR ATmeg8 as the main chip.

Want to try build this microcontroller project? download document, source code, sachematic here (zip file)
[source]

Windmeter using Microcontroller

The Windmeter is an anemometer designed to measure and record wind speed distribution from 0 to 17+ meters per second. It was designed for high reliability, ease of construction, and for a wide environmental range. Data is logged over a period of 30.46 days (1/12 of a year), and then saved for 11 months. The data can be retrieved with a laptop computer any time within the 12 months of logging. The Windmeter is self-powered by a solar pannel and battery. Calibration of the Windmeter can be done against a car's speedometer or better yet a GPS receiver. The Windmeter should cost you under $300 to make.

[source]

Flickr images on a Nokia LCD and AVR

Another electronic project related to LCD. Alex has created microcontroller project : Flickr images on a Nokia LCD. The "brain" used microcontroller AVR ATmega48 and the software, he decided to fetch images from Flickr using Beej’s Python Flickr API.
Is it difficult to bulid this cool microcontroller project? well, if you follow what alex said i'm sure you can do it. May be i'll built it someday :)

Links & Downloads

• nokia_lcd.zip, Source and schematic
• Sparkfun’s Color LCD, with a lot of sample code
• Datasheet Philips PCF8833
• Epson S1D15G10
• Nokia Display with an Atmel-AVR
• Flickr API

source : tinkerlog.com

PCB Drill Project

This PCB drill project created by Shawn Kelly. This is one of cool electronic project. According to him, The moving part is the tabel not the drill head. To make sure everithing work fine, the project tested with Labcenter's Proteus VSM / Isis. With this PCB drill, it will saving our time to drill pcb when build electronic project.
[source]

PIC Universal Receiver Infrared

The Universal Infrared Receiver (UIR) is a device that enables you to control your PC based application like PC home thaater with ANY remote controller you have (TV, VCR, CD or Stereo). Original hardware & software was designed by Martinus & Ties Bos. this projcet using microcontroller PIC12C508A.

Download
hex file

If you want build VCR without microcontroller you can try this schematic. To use it you need a plugin for Girder. I don't know if the plugin will work with other control software.

[source]

Electronic Project : AVR Lux Meter

The illumination is how the level of flows of light falling on a surface. . The flow of light is visible, which is defined in the flow (the light power) divided by relative sensitivity of the naked eye on the visible spectrum. This means that the Lux is well suited to the light level of meaning to the human eye. To measure the lighting, we can use Lux Meter.

We can build ourselves Lux meter using electronic components. At the detection of light we use photo diode. However, there is a difference between the spectra simple answer photo diode silicon and the naked eye, it can not be used for lux meter. Some photo diodes for lighting have a sensor compensation color filter on the window to correct its response spectra.

In this project, Photo-diode current results light that is well proportional to the light input power when used in short fashion. In this lux meters, the output current is converted into a voltage converter with an IV, he is caught by a micrcontroller AVR and displayed in terms of lux. The ppamp U1 in the circuit diagram that acts IV conversion circuit and its conversion becomes 50mV / μ A, in accordance with a record of comments R5. The capacitor C5 is to obtain the correction, it cancels Ct of the photo diode (about 200 pF). In this case, greater capacity in May rather be 220 pF because the high frequency signal is not necessary. The lux meter is powered by a 9V battery.

Download schematic, document, firmware (zip) here
[source]

Dot Matrix Project : Fancy Leds

The idea of this project came from Olivier de Broqueville's son. He was dreaming of a small tool able to write symbols or pictures on a screen. If using a graphic LCD, it was too expensive (or too easy?), so the solution adopted was to pilot a dot matrix of Leds. The Dot matrix project need only some cheap transistors, common red Leds, and a PIC microcontroller 16F628. And the dream could become reality.

Download for the document,source code, software and schematic here (zip file)
[source]

Project : Persistance-of-vision LED Sphere

The goal of this project was to develop 3D spinning mechanism capable of displaying smooth video or static images. The device uses a spinning ring with tri-color LEDs inside, and relies on precise angular sensing and persistance-of-vision and to create the effect of a spherical display surface. Although the system consists of only a single ring of LEDs, the high rotational speed makes it possible to display any combination of red, green, or blue pixels along the surface of the resulting sphere. (3-bit color depth!)
[source]

PIC Robotic Webcam

Main parts to built PIC robotic webcam are two servo motors and microcontroller PIC. This eletronic project not too hard to build it if you have some electronic basic and programming the microcontroller. For the main processor this project utilized PIC 16F84. The total cost of the project is about 40 Euro (40$). All the software/code can be downloaded as free or shareware.

Download program and free servo controller here
[source]

How to Hide Secret Data in image and audio files Ubuntu / Debian: Steghide

steganography is the technique used for hiding various data in different type of image and audio files with out changing the basic characteristics of file. Steghide is a utility for steganography. The color- respectivly sample-frequencies are not changed thus making the embedding resistant against first-order statistical tests.

Features include:
* Compression of embedded data
* Encryption of embedded data
* Embedding of a checksum to verify the integrity of the extraced data
* Support for JPEG, BMP, WAV and AU files

How to install steghide in Ubuntu / Debian
Open a terminal
$apt-get install steghide (or Use Synaptic Package Manager)

Basic Usage
$ steghide embed -cf picture.jpg -ef love.txt
  Enter passphrase:

  Re-Enter passphrase:

  embedding "love.txt" in "picture.jpg"... done

This command will embed the file love.txt in the cover file picture.jpg

After you have embedded your love letter love.txt data as shown above  and you can send the file picture.jpg to your lover.

Now How to extract file

$  steghide extract -sf picture.jpg
Enter passphrase:
the file "love.txt" does already exist. overwrite ? (y/n) y
wrote extracted data to "love.txt".

This will give file information

steghide info picture.jpg
"picture.jpg":
  format: jpeg
  capacity: 1.2 KB
Try to get information about embedded data ? (y/n) y
Enter passphrase:
  embedded file "love.txt":
    size: 34.0 Byte
    encrypted: rijndael-128, cbc
    compressed: yes

PIC Room Timer

The purpose of this electronic project is to present a device that is useful and at the same time demonstrate to the beginner many features involved in programming the PIC. Some of the topics included are:

* Simple use of MPASM assembler
* Demonstration of use of timer 0 and the prescaler
* Use of length of instructions to set up timing delays
* Using interrupt routines
* Detection of switch closures including debouncing
* Saving and recovering data from the onboard EEPROM


Download the source code (.asm)

[source]

PIC Universal RC5/RC6 transceiver

This is another Universal RC5/RC6 transceiver project. It use PIC16F628 as main processor. On the one side you can read the RC5, RC5X and RC6 codes from remote controls on a LCD and on the other hand you can send all thinkable RC5, RC5X and RC6 codes to a device.

Download IR-TRC_U.HEX, V-3 file to program in a 16F628(A)

Download Transceiver_V-3_UK.bas, the sourcecode for PIC Basic

Download scheme as PDF file

PCB layout 110820 as PDF file

Datasheet HD44780.pdf LCD (Liquid Crystal Display)

Datasheet TSOP1736.pdf infrared receiver

source

How to Synchronize a local directory with a remote directory using rsync in ubuntu

Most of the system administrators need to sync some of  their local folder to remote folder. You can do this with a simple command line utility rsync. This will synchronizes files and directories from one location to another , securely by using  delta encoding. It will synchronize files across the network by transferring only data that has changed.

Open a terminal

$sudo apt-get install rsync

$ rsync -r -a -v -e "ssh -l shibu" --delete 192.168.0.5:/var/www/ /home/shibu/public_hrml

$ rsync -r -a -v -e "ssh -l shibu" --delete ceattingal.ac.in:/webroot/ /local/webroot 

rsync command common options

• --delete : delete files that don't exist on sender
• -v : Verbose
• -z : compress file data
• -e "ssh options" : specify the ssh as remote shell
• -a : archive mode
• -r : recurse into directories

MICRF102 Based RF data logger

Telemetering is a methode to measure voltage, temperature or any other variable which long distance between censor and data processor. There are many ways to implement telemetering, one of them using wireless RF data logger. What do you need with this project is Rf transmitter, RF receiver and Data processor (PC) . Any number of these recorders transmits data packets to a central PC-based receiver. A PC program stores the information for later analysis.

The RF data logger project use small RF IC's the MICRF102 from Micrel because it's good compromize between price and complexity. The MICRF102 is a low power ASK transmitter IC. It generates UHF frequencies by PLL multiplying a crystal oscillator frequency by 32. In this case a 13,56MHz crystal provides a 433,925MHz carrier. The data recorder is controlled by a small AVR TINY45 microcontroller.

Download schematic RF transmitter (gif)
Download schematic RF receiver (gif)
[source]

PIC Microcontroller based Doorbell

If you new in microcontroller project. May be you want to build just a simple electronic project. Like Doorbell created by Quozl. He used microcontroller PIC 16F84 for the main processor. I know that we can build simple doorbell without microcontroller. But, take a look the feature of this project.

A microcontroller driven doorbell circuit with features:

* one second instant pulse output,
* one second delayed pulse output,
* two minute lighting output,
* latching has been triggered indicator,
* processor alive indicator,
* ignore additional trigger for preset duration.

Do you want to build the project? Ok, here is the source code, schematic and the pcb.
source

Simple AVR Project : Battery Monitor

Batwatch is a simple monitor for a solar panel battery charger, using an Atmel ATtiny13V. It periodically measures the charge current and battery voltage, and shows them by blinking two LEDs. I built this circuit into the plug of a VW solar charger panel that is used to prevent a discharge of the battery when a car is not used for some time. A modern car contains a large amount of electronics, and a quiescent current of 40-50mA (about 1Ah per day!) is considered "normal".

Download the batwatch project, schematic

PIC based RFID reader

RFID cards are commonly used for access control and bus/train tickets. They are convenient because no direct contact is required to transfer information to and from the card. The card itself is powered by the RFID reader, so there is no battery to change.

For the experiments, He use a HID ISOProx card. These cards are the simplest of all RFID cards as they only stores a single serial number and uses no encryption. The carrier frequency is 125 KHz. For processing the data, the project uses microcontroller PIC 16F628A.

Interesting to build it?

Download the schematic 1, schematic 2.

Script for Finding Size of All Folders in Linux

Some users will eat lot of space in the system by storing unwanted files. This bash script will help you find which folder using more space.

Open a terminal
Then cut & Paste the script

for f in * ; do if [ -d "$f" ]; then du -sh "$f" ; fi done | sort -n

PIC Project : Infra/radio remote control transmitter/receiver

This is a general purpose remote control project with programmable PIC microcontrollers. Schematics are shown for using infrared (RF) or radio (RF) media. If you are not familiar with microcontroller programming, you can use fixed encoder and decoder integrated circuits instead. Well-known such IC-s are Holtek HT-12D, HT-12E and Motorola MC145026, MC145027, MC145028.

Remote controls usually consist of encoder/decoder parts connected to a transmitter/receiver module which takes care of the transmission of digital signals by radio or infra waves. The format of this project's signal is designed to be ideal even for the cheapest ASK RF modules (using 50% signal/silence ratio), and it is similar to the Philips RC-5 format used in infrared remote controls. The transmitter has a varying number of buttons and sends the states of these inputs to the receiver. The receiver device decodes the message and sets the outputs accordingly.

Download : schematic IR(jpeg), schematic RF
source

search term : PIC microcontroller project, Infra Radio Remote controll, Trnsmitter and receiver project

PIC Project : Alarm Security System

This Alarm Sytem is based on two PIC12C508 (one is used in transmitter and the other one in the main unit). The following PICs are supported: 12c508, 12c509, 12c508a, 12c509a, 12ce518, 12ce519, 12f508, 12f509, 16f84 and 16f84a. Transmitter uses infra red beam to send code name to main unit. The commands are:

* Arm/Disarm
* Silent Arm/Disarm
* Weak battery in transmitter

It implements the folowing features:

* IR remote keyless system
* 72 bits transmission length (64bits password, 4bit CRC, and 4bits for commands)
* Arm/Disarm
* Immobilizer
* Two stage sensors, door and shock sensor trigger inputs
* Locking/unlocking of doors
* Normal/Silent modes
* Inside zone intrusion memory
* Transmitter low battery indication

This system is a perfect solution for unidirectional remote keyless entry systems and access control systems. Such system may be implemented in:

* Automotive alarm systems
* Automotive immobilizers
* Gate and garage door openers
* Burglar alarm systems

Download :
Here you can find transmitter assembler code (updated on March 11, 2008) and a password.inc file. Don't forget to change processor type in MPLAB or you will get errors. I've added PIC16F84 family processors for debug. And also you can find main unit assembler code.

Schematic :
Download Transmitter schematic, main unit schematic, IR Receiver schematic, IR Receiver Schematic Diagram (TBA2800 Based)
src

Electronic Project : Simple IR (Infra Red) Receiver

I guess this is the simplest IR receiver circuit i ever know. It's only use few pasive component and TSOP 1738 IR receiver that housing on Sub-D 9-pin serial box.

tags : IR Receiver, simple electronic project, digital project link

Traffic Light Control Circuit

This electronic project based only on 74LSxx family and IC 555 as clock source. It's a digital logic circuit. To build Traffic Light Control you don't need microcontroller programming.

This page features a circuit that has twenty open collector outputs that turn on one at a time in a continuous sequential manner. The circuit make use of the 74LSxx family of TTL integrated logic devices. The circuits are designed to drive light emitting diodes or low current, low voltage incandescent lights but can also drive other loads of up to 80 milliamps.

download : schematic

tags : traffic light circuit, digital logic circuit, electronic project link

How to Change Sudo Password Remembering Time in Ubuntu

When You use 'sudo' command it will ask for password in First time and will remember password for 15 minutes. It is a security hole for sensitive systems.
You can change sudo Password Remembering Time in Ubuntu .

Open a terminal and type
$ sudo visudo

In Ubuntu, visudo uses nano text editor, and what it does is edit the / etc / sudoers.tmp

Check for the line as shown below

Defaults        env_reset


Change it to

Defaults        env_reset , timestamp_timeout = X

Where X is the time that we remember the sudo password, if we put 0 (zero) that we always get the request.

Finally to save the changes, press Ctrl + X and said yes.

PIC Autorange Capacitance Meter

This electronic project is really powerful capacitance meter. This is an autoranged Capacitance Meter version, which means one does not need to adjust the range settings. Furthermore, the measuring range is quite large, from 5pF all the way to 2600uF. It is all taken care of by the PIC16F873A inside the circuit.

It is based on a very simple circuit analysis principle of charging and discharging of capacitors in an RC circuit.

download : schematic and source code

Capacitacance Meter, Metering Circuit, microcontroller PIC Project link

R/C Transmitter Range Tester

This project suitable for people who like with the transmitter system. It's an electronic analog project. You don't have to programming the IC to build it. The function of this electronic project is to measure the RF power being radiated from a transmitting antenna.

Among the Amateur Radio fraternity, a device such as the one described here would otherwise be known as a Field Strength Meter (FSM). Its main purpose would be to check that RF power is being radiated from a transmitting antenna. Some FSMs are tuneable across a wide range of frequencies, which allows the device to work with different transmitters and antennae - usually from HF to VHF and beyond. A difference with this unit is that it is only sensitive to those signals in the R/C section of the radio spectrum. The on-board trimmer allows you to tweak for maximum signal strength of your frequency of choice, whether it be 27MHz AM, or 40MHz FM.

In order to read the received signal strength, such a unit would ordinarily employ a mechanical analogue meter. The unit described here differs in that it uses four super-bright LEDs. The benefit of this is that it allows you to read the display from a distance - even in bright sunlight.

Download : schematic(gif), PCB1, PCB2

tags : Electronic Circuit Project, FM tranmitter, Field Strength Meter, Analog circuit (src)

Electronic Project : Servo Tester 2

If you want to check your Servo, i think this electronic project is suitable for you. The project use microcontroller AVR AT mega 16 as main processor. The Servo Tester 2 is hardware and software that, basically, makes a pulse width signal between 1 and 2 ms. This is the signal used to control common R/C servos. This one has some advanced features, not usually found on servo testers. This project created by ejberg

Feature list:

• Generates two separate signals for driving two servos.
• Sweep mode for stress testing servos.
• Input for reading a servo signal (from a receiver).
• Receiver signal quality analysis.
• Very high resolution at both input and outputs. 0.1µs (which equals 10,000 steps between 1 and 2 ms).
• Voltage and current readout. How much current does your servos actually consume? How much does your receiver pack drop under load?
• Simple user control. Access all features with just a single rotary knob with integrated push button.
• 2 x 16 character LCD.
• Optical tachometer.
• RS-232 connection. Write your own program (PC or whatever), that can control every feature of the tester.

Download :

Make sure you have read the license conditions, and that you agree with them, before downloading any files.

Hardware

Schematic page 1	servotester2_1.png
Schematic page 2	servotester2_2.png
Schematic page 3	servotester2_3.png
Board (Eagle format)	servotester2.brd

Software

Program file. Version 1.00	servotst2.hex
Source in AVR assembler. Version 1.00	servotst2.zip

Documentation

User manual	Servo_Tester_2_user_manual.pdf
One-page menu overview	menu_overview.pdf

Servo Tester, electronic circuit project, Tachometer (src)

RS485 to RS232 Converter

Converter is intended to use with PC computer to communicate with ROV using 2 wires in half duplex mode. Send/receive mode is selected by RTS signal. The converter was designed to be as simple as possible, so it has no some features that can be found in commercial grade products (e.g. galvanic separation).

Popular chip MAX232 is used to convert RS232 signals from/to TTL level. MAX485 converts TTL level signals to RS485 standard. RTS line is used to change transmission mode of MAX485. RTS signal is first converted to TTL level by MAX232 then connected to DE and RE/ pins. 2 LED are used to indicate current state of the interface.

download

RS485_to_RS232_Converter_Schematic.pdf

RS485_to_RS232_Converter_Elements.pdf

RS485_to_RS232_Converter_BOM.pdf

RS485_to_RS232_Converter_PCB.pdf

tags: Electronic Circuit project, RS485 to RS232 converter, Digital circuit (src)