For those who are trying to make AVR kit at home, an AVR programmer which can be simple to make will be really useful, as it’ll avoid buying the programmer!! Here I’m giving a few webpage links on how to make a programmers yourself.
DIY AVR Programmers - [Link]
Using graphic LCD in a project gives itreally a good look and flexibility of displaying different characters and shapes. But, the graphic LCDs are quite costly.
The NOKIA 3310 LCD provides a really low-cost solution to add a small graphic display into your project and also good for learning purpose. The LCD is SPI bus compatible, saving many pins for other uses. It operates at 3.3v.
NOKIA 3310 LCD interfacing with ATmega8 – [Link]
Now, here I’m presenting one application with the same LCD: Designing a thermometer using DS1621 temperature sensor IC. DS1621 is 8-pin sensor from Maxim, with temp range of -55 to +125 degree C, which can be interfaced with microcontroller over two-wire serial i2c bus. It has operating voltage range from 2.7 to 5.5v. I’m operating it here at 3.3v, same as the one driving the LCD and ATmega8. DS1621 doesn’t require any external components to measure temperature. It has got continuous or one-shot temperature reading capability to save power.
Thermometer using DS1621 and Nokia 3310 LCD interfaced with ATmega8 – [Link]
Here is a small project of Analog to Digital Converter using ATmega32 which is having on-chip 8-channel ADC.
The circuit also consists of an intelligent 16×2 LCD for displaying the value of the voltage applied at each channel. There is also a push-button to scroll through the different channels.
8-Channel ADC Project with ATmega32 - [Link]
Here is a very simple project of controlling a small DC-motor (taken from an old personal cassette player) with ATmega8. The ATmega8 is having three PWM channels, out of which two are used here. PWM waveforms are fed to MOSFET (RFD3055) H-bridge. Here, direction is controlled using a two-position toggle switch and speed of the motor is controlled by two push-buttons, one for increasing the speed and other for reducing.
Simple PWM DC motor control using MOSFET H-Bridge with AVR ATmega8 - [Link]
Here is a project for beginners to interface a 16-key (4×4) keypad with ATmega32 using 8-pins i.e. one port of the microcontroller. This is useful particularly where we need more keys but don’t want to spend more uC pins for interfacing.
The 4×4 keypad is a standard one available in the market. I’ve used here one from my earlier project. The LED shown in the schematic is just extra, which can be used anyway you like.
4×4 Matrix Key-board Interfacing with ATmega32 – [Link]
Here is my project on interfacing of SD Card (microSD). microSD cards are available very cheap nowadays, a great option for having a huge memory in any embedded system project. It is compatible with SPI bus, so the interfacing is easy. SD card adapters are also easily available in market, one can easily make a bread-board adapter by soldering few pins on it. Following figures show the SD card pin-out & the bread-board adapter design by soldering 7-pins of a breakout header on the microSD adapter
SD/SDHC Card Interfacing with ATmega8 /32 (FAT32 implementation) – [Link]
Aim of this project is to present a way to store a large quantity of data into microSD card in files with FAT32 format. Here, ATmega32 is used for data collection and microSD interface. The data is received from in-build 8-channel ADC of ATmega32. One channel is used for reading temperature from LM35 sensor and remaining channels are used for simply reading voltages and storing them.
microSD ATmega32 Data-Logger - [Link]
dangerousprototypes.com writes: [via]
Here’s a good tutorial from ExtremeElectronics.co.in explaining the types of stepper motors, their uses, and how to interface them with an AVR microcontroller.
It includes the xstepper code library for use with the AVR Atmega16, and demonstrates how to interface the MCU and the motor using a ULN2003A high-voltage high-current Darlington transistor array.
This tutorial is comprehensive and provides beginners with the theory and sample code to get started with a simple stepper motor project.
Stepper motor tutorial – [Link]
Cree, Inc. reports another industry-best efficacy record of 231 lumens per watt for a white power LED. This result is a significant advance beyond Cree’s previous industry record and further demonstrates how Cree’s relentless innovation continues to push the boundaries of what is possible with LED lighting. [via]
231 Lumen per watt LED shatters LED efficacy records - [Link]