Tiny Morse Code Trainer

June 23, 2011 by Brian Benchoff 18 Comments

[Eric] wanted to teach his kids Morse code, so he built a tiny Morse code trainer.

[Eric] built the trainer around an ATtiny85, and the rest of the circuit follows this minimalist idea. After connecting a piezo beeper and 6-pin ISP header, the only thing left to do was write a little code and start teaching his kids Morse. The Morse trainer is programmed to repeat the message, “SOS the moon rover has broken down and I am stuck in the trash can in the garden shed,” [Eric] planted a Lego moon rover in his shed as a prize for learning Morse, making him one of the coolest dads ever.

Although learning Morse isn’t required for an amateur radio license anymore, it’s a requirement for continuous wave radio. We think this is a great way to learn Morse the right way – actually hearing the characters – instead of memorizing the Huffman tree of Morse characters.

Programming An ATtiny Using An Arduino

May 29, 2011 by Mike Nathan 24 Comments

attiny

[Scott] is a big fan of the Arduino platform, and he’s not afraid to admit it. It does all the things he needs, but now and again he would like to use something a bit smaller, without all the bells and whistles the Arduino has to offer. He contemplated using an ATtiny for smaller projects, but after looking into what he would need to program the chip under Linux, he could never find the motivation to give it a go.

That all changed when he discovered the Arduino-Tiny project, which aims to bring a limited Arduino IDE to the ATtiny line of microcontrollers. He found the project to be quite useful, so he put together a brief tutorial that walks through everything you need to get started.

The tutorial is fairly straightforward, and even demonstrates how the Arduino can be used as an ISP for the ATtiny, removing the need to purchase a standalone programmer. Be sure to check it out if you are searching for an easy way to get started with ATtiny chips under Linux.

A Charlieplex Display And A Board Layout Tip

February 7, 2011 by Mike Szczys 7 Comments

[Ben] is getting himself up to speed with microcontrollers. He jumped into the deep end by taking on this Charlieplex LED matrix build. As you can see after the break, he not only made the display work, but coded Conway’s game of life to run on the ATtiny85 that drives the device. What you see above is the prototype version that [Ben] used to make sure he had the hardware just right. He’s seeing the project through to a manufactured board and this is where the layout tip comes from. In order to make sure he had enough space for all of his components he printed out the board artwork, taped it to some Styrofoam, and then inserted all of the through-hole parts. Now he can be sure that physically the design works, we’ll keep our fingers crossed that everything is also kosher electrically.

Continue reading “A Charlieplex Display And A Board Layout Tip” →

LED Lighthouse Simulator

December 27, 2010 by Mike Szczys 11 Comments

This Christmas [Bill Porter] decided to show his parents that those college dollars were well spent. He upgraded the custom lighthouse light which he originally designed in high school for their garden fountain. He even went so far as to craft some retail-worthy packaging for the gift.

We think it’s a wonderful design, on a custom PCB and based around an ATtiny85. A real lighthouse has a spinning lens to aim the beam of light. When the lens sweeps across your viewpoint there is a sudden flash and he’s recreated that effect using PWM. Take a look at the video after the break and you’ll see what we mean.

Also, during development he was plagued by a startup glitch which we got majorly sidetracked reading about. Continue reading “LED Lighthouse Simulator” →

Christmas Tree Low-water Monitor

December 8, 2010 by Mike Szczys 24 Comments

The end of the year is rapidly approaching and there’s a good chance you have a slowly dying tree in your living room. Help it hold on a little longer by using [Eric Ayars’] Christmas Tree water monitor. He’s built a sensor out of a piece of strip board. Three bus strips on the board allow for a variety of alerts. When all three are submerged everything is ok. When the two longer traces are still under water but the third is not an LED will blink to let you know it’s time. If you don’t pay attention and there’s no water left, a piezo buzzer makes noise until you add water (or the coin cell runs out of juice).

This project centers around an ATtiny85 that [Eric] programmed using an Arduino, one of the methods we covered in our AVR Programming Tutorial. But if this simple circuit isn’t high-tech enough for you, we saw a similar method last year that will send an alert to your iPhone.

Tiny USB Business Card

October 29, 2010 by Mike Szczys 43 Comments

[Frank Zhao] put together a USB business card. It’s even got the instructions printed right on the silk screen of the PCB explaining how it should be used. He based the design around an AVR ATtiny85 microcontroller. It runs the V-USB package that handles USB identification and communication protocols. The rest of the hardware is pretty standard, the uC draws power from the 5V USB rail, with a couple of 3.6V Zener diodes to drop the two data lines down to the proper level.

Once plugged in it waits until it detects three caps lock keypresses in a row, then spews a string of its own keypresses that type out [Frank’s] contact information in a text editor window (video after the break). It’s not as reusable as the mass storage business card because [Frank] didn’t breakout the pins on controller. But we still enjoy seeing business cards that make you stand out.

This is a great project to tackle with your newly acquired AVR programming skills.

Continue reading “Tiny USB Business Card” →

World Smallest TV-B-Gone

July 4, 2009 by Zach Banks 41 Comments

uTVBG

The TV-B-Gone has proven to be a dangerous and versatile gadget. At Interactive Matter, they created an even smaller version with more sneaking potential. Called the µTVBG, it packs an entire TV-B-Gone in a 1.4 x 2.5 cm footprint and even has room for a programming header. He found some high-powered surface-mount IR LEDs that would match the original TV-B-Gone’s power. To drive the board, they used a CR1220 button battery on the bottom of the board. The whole thing is smaller than your thumb and should be easier to hide next time you wreak havoc.