AVR

337 Articles

MIDI Sequencer/controller

June 13, 2009 by 12 Comments

lenonluks

Reader, [Lennon Luks] made a really slick  MIDI sequencer/controller for his senior design project while studying at Western Carolina University. It has a grid of 64 LED buttons, 8 knobs, and a display with navigation buttons that allow him to sequence tracks with or without a computer. The controller is based off an ATmega644 and is programmed in C. [Lennon] clearly explains the inner workings of the project in detail on his website and has included a good number of pictures. [Lennon] made a nice video of the project which can be seen after the jump.

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Space Invader Button

April 14, 2009 by 36 Comments

spaceinvaderbutton

[Marcus] saw [Alex]’s 64 pixel project and decided it could be implemented in even less space. Pictured above is his Space Invader button with a bicolor LED matrix. The controller board is all SMD and piggybacked on the matrix. An ATmega164P drives the 24 pins via transistors. In addition to animation, the board can do LED sensing too. It’s a very clever project and [Marcus] has some notes about working with such tiny components. You can see a video of it below. Continue reading “Space Invader Button” →

Rocket Acceleration Logger

April 8, 2009 by 17 Comments

rocketdatalogger

Have you ever wondered how high or how fast a model rocket goes when you launch it? [sprite_tm] did, so he decided to build a low cost, lightweight data logger that he could fit into the nose cone of his rocket. To keep the circuit small, he built it around the popular ATtiny13 microcontroller. The microcontroller collects data from a Freescale MMA7260, a 3-axis accelerometer that he extracted from a third-party Wii nunchuck controller. After the microcontroller collects the data, it’s stored in 32K of EEPROM on a 24C256. All of this is powered by a small 3.6v Li-ion battery, which is the largest part of the circuit. If this sounds like something you’d like to make, he has detailed instructions along with the software used available on his site. While we don’t launch a lot of model rockets here, we may soon start just so that we have an excuse to build this.

Brew Fridge Thermostat

March 22, 2009 by 32 Comments

thermostat-1

Reader [Will R] sent in a thermostat mod for his brew fridge. His friends had found a perfectly fine bar refrigerator and wanted to repurpose it for brewing beer. A previous batch of microbrew had been mangled by the Australian heat so they wanted something that could maintain the perfect temperature. The fridge’s built-in thermostat wouldn’t rise above 5 degrees so they had to build their own. [Will] used a 10K NTC thermistor to measure the temperature. It’s connected to an ATtiny25 microcontroller that does the comparison and determines whether to turn on the compressor. He referenced SparkFun’s relay tutorial for the switching side. Although he didn’t etch a board for this project, the design file is included along with all the code on the project site.

64pixels Are Enough

March 21, 2009 by 7 Comments

64pixel

[Alex] put together this lovely minimal LED project. The square pixel matrix is soldered directly to the microcontroller in the same style as EMSL’s Micro-Readerboard. During the prototyping phase he used resistors to limit the current from the programming board. The final product doesn’t use resistors and manages the current draw by only turning on a single pixel line at a time. The illustrated assembly guide is very thorough and should help your create an equally compact device. Check out a video of it in motion below.

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Arduino MEGA

March 16, 2009 by 53 Comments

arduino_mega

Evil Mad Scientist Laboratories spotted one of the first images of the Arduino MEGA. The board is based on the ATmega1280 microcontroller, which has 128KB of flash,4KB of RAM, and 4KB of EEPROM. We haven’t seen any official specs yet, but the silkscreen shows 12 PWM connections, 36 Digital I/O, and 16 analog inputs. The post mentions 4 hardware UARTs and an I2C bus as well. No release date yet, but we can assume it’s soon since the hardware was already demoed at ETech.

Related: We added an Arduino category.

STK500 As An Arduino

March 8, 2009 by 5 Comments

stkarduino

The AVR STK500 has been Atmel’s standard AVR development platform for many years. Recently though, hobbyists have embraced the Arduino. [Alessandro] has decided to bring the two together so that you can use the Arduino environment with the STK500. Unlike the Arduino, it comes with 8 LEDs, 8 switches, a variable power supply, and variable analog reference. It’s a great way to get hardware you might already have back into service.