A Tiny Robot Family


Back in the late 80s and early 90s, a lot of young electronics hobbyists cut their teeth with BEAM robots – small robots made with logic chips and recycled walkmans that tore a page from papers on neural nets and the AI renaissance of the 80s. Twenty years later, a second AI renaissance never happened because a generation of genius programmers decided the best use of their mental faculties was to sell ads on the Internet. We got the Arduino, though, and the tiny robot family is a more than sufficient spiritual successor to the digital life of the old BEAM bots.

The tiny robot family is [shlonkin]‘s growing collection of small autonomous vehicles that perceive the world with sensors and act with different behaviors. They all contain an ATtiny85, a small battery, two motors, and at least one phototransistor and a LED. One robot has left and right eyes pointing down, and can act as a line follower. Another has a group of LEDs around its body, allowing it to signal other bots in all directions. The goal of the project is to create a whole series of these tiny robots capable of interacting with the environment and each other. Video of the line follower below.

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DUO Decimal – a Minimalist Single Board Computer


If you’ve ever struggled to fit your program into the RAM and ROM of a small micro, you’ll appreciate [Jack's] creation, the DUO Decimal. DUO Decimal is a small single board computer running on an Atmel ATtiny84. The ’84 has 8KB flash memory, 512 bytes of SRAM, and 512 bytes of EEPROM. Not as bad as a the old days, but still tight by today’s standards.

User input to the DUO Decimal is through two buttons. Output is via a 7 segment numeric LED display. Not the easiest for typing in long programs, but on par with the switches and blinkenlights of the past. 3 bits of GPIO are available for connections to your own circuits.

[Jack] didn’t just design a board, he designed an entire language. DUO Decimal is programmed in an interpreted language called DUO Decimal Numeric Code (DDNC). There are 47 DDNC commands, covering everything from basic math to list manipulation. Programs can be entered through the buttons, or save your fingertips by downloading them through the AVR isp interface. The entire C code for the DUO Decimal, including the DDNC interpreter is available on [Jack's] website.

[Jack] created several example DDNC programs, including a 6 function calculator with trigonometry, a Mandelbrot set tester, and an implementation of the rock paper scissors game. There’s even a platformer action game, though graphics on a single 7 segment display are simplistic to say the least.

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Solderless Noise-o-Tron Kit Makes Noise at Chicago Makerfaire


Anyone who’s manned a hackerspace booth at an event knows how difficult it can be to describe to people what a hackerspace is. No matter what words you use to describe it, nothing really seems to do it justice. You simply can’t use words to make someone feel that sense of accomplishment and fun that you get when you learn something new and build something that actually works.

[Derek] had this same problem and decided to do something about it. He realized that in order to really share the experience of a hackerspace, he would have to bring a piece of the hackerspace to the people.  That meant getting people to build something simple, but fun. [Derek's] design had to be easy enough for anyone to put together, and inexpensive enough that it can be produced in moderate quantities without breaking the bank.

[Derek] ended up building a simple “optical theremin”. The heart of this simple circuit is an ATTiny45. Arduino libraries have already been ported to this chip, so all [Derek] had to do was write a few simple lines of code and he was up and running. The chip is connected to a photocell so the pitch will vary with the amount of light that reaches the cell. The user can then change the pitch by moving their hand closer or further away, achieving a similar effect to a theremin.

[Derek] designed a simple “pcb” out of acrylic, with laser cut holes for all of the components. If you don’t have access to a laser cutter to cut the acrylic sheets, you could always build your own. The electronic components are placed into the holes and the leads are simply twisted together. This allows even an inexperienced builder to complete the project in just five to ten minutes with no complicated tools. The end result of his hard work was a crowded booth at a lot of happy new makers. All of [Derek's] plans are available on github, and he hopes his project will find use at Makerfaires and hackerspace events all over the world.

The p.u.l.s.e Parking Light

Pulse[Anool]‘s brother loves his motorcycle, and when he came across a ‘breathing LED’ mod for the brake light, he had to have one. Being tasked with the creation of a pretty cool mod, [Anool] came up with p.u.l.s.e., an extremely small LED controller and a slight tip ‘o the hat to Pink Floyd and the second or third greatest CD packagings.

The circuit is a slightly Apple-inspired mod for the  parking light that keeps the lamp fully lit when the Neutral Detect line on the bike is high, and slowly pulses the LED in a ‘breathing’ pattern when the Neutral Detect line is low. Not a lot of logic is needed for something this simple, so [Anool] turned to the ATtiny45 and the Arduino IDE to accomplish his goal.

[Anool] created a circuit in KiCAD that would plug in to the lamp socket of his brother’s bike. A cluster of LEDs replace the T10 lamp inside the parking light, and a small amount of code takes care of the logic and breathing effect. It’s a great mod, and the astonishingly small size of the board puts him in the running for the smallest Arduino we’ve ever seen.

Videos of the light in action below.

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ATtiny85 Data Acquisition


The folks at Ivmech recently had a need for some new hardware. They needed a small, cheap device able to sense some analog values, toggle a few digital pins, and log everything to a computer. What they came up with is the IViny, an extremely small data acquisition device built around the ATtiny85, capable of logging data to a computer.

The IViny features two digital channels and two 10 bit analog channels, just like you’d find in any ATtiny85 project. Power is supplied over USB, and a connection to a computer is provided by V-USB. There’s also a pretty cool Python app that goes along with the project able to plot the analog inputs and control the digital I/O on the device.

It’s not exactly a fast device – the firmware only supports 100 samples per second, but an upcoming firmware upgrade will improve that. Still, if you ever need to read some analog values or toggle a few pins on the cheap, it’s a nice little USB Swiss army knife to have.

NES Cartridge Hack Makes Great Novelty Gift

NES cartridge with arduino

Most all of us recall the Blinking Screen of Death on original NES systems. This was caused by a bad connection between the cartridge and the NES cartridge connector. For whatever reason, it became a very popular idea to give a quick blow down the cartridge, even though this didn’t really help. [Dale] decided to play on this annoying problem by making the NES Blow Cart!

Inspired by a previous cartridge hack, [Dale] mounted a custom made circuit sporting the ever popular ATtiny85 in a Super Mario / Duck Hunt cartridge. A small microphone sits where the original cartridge connector was, along with the on/off switch and program header. A quick blow triggers the ATtiny85 to play a song.

The most difficult part for [Dale] was to figure out how to get the ATtiny to play “music”. This was solved with the discovery of a library called Rtttl. This allowed him to take old Nokia Super Mario and Zelda ringtones and get them on the Attiny85. All files, including the rtttl library are available on his github. Be sure to stick around after the break for a video of the project in action.

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Digispark Pro, The Bigger Smaller Dev Board


There has recently been a huge influx of extremely small dev board based on the ATtiny85. This small 8-pin microcontroller is able to run most Arduino sketches,  and the small size and low price of these dev boards means they have been extremely popular. The Digispark was among the first of these small boards, and now the creator is releasing a newer, bigger version dubbed the Digispark Pro.

The new board isn’t based on the ‘tiny85, but rather the ATtiny167. This larger, 20-pin chip adds 10 more I/O pins, and a real hardware SPI interface, but the best features come with the Digispark Pro package. There’s real USB programming, device emulation, and serial over USB this time, and the ability to use the Arduino serial monitor, something not found in the original Digispark.

There are also a few more shields this time around, with WiFi and Bluetooth shields available as additional rewards. Without the shields, the Digi Pro is cheap, and only $2 more per board than the original Digispark.