Sparrow is a small DIY dev board based on an ATtiny13

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This project is bringing AVR development to mobile devices. 

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Created by Thomas Baum as an entry for the 2015 Hackaday Prize, Sparrow is a cloud-based microcontroller system driven by an ATtiny13A and configured using the stereo signal from a mobile device’s headphone jack. The Maker had set out to develop a web-based service for AVR programming with smartphones and tablets, in an effort to minimize some of today’s most common barriers.

“Smartphones and tablets are starting to replace traditional PCs. In the nurseries of the new generation mobile devices are already widely used. Even in developing countries mobile phones are found everywhere, but not everybody has their own PC,” Baum explains. “But are these devices suitable for development or electronic experiments? Try to write an app on a smartphone. In the area of microcontrollers, the problem lies in the closed systems. Interfaces are available but not uniform and not readily accessible from the browser.”

Baum notes that apps can be downloaded right from the Internet and directly uploaded to the controller via a browser that supports HTML5 audio tags. Those looking to develop their own programs can do so as well through an online assembler and C compiler. With Sparrow, the stereo signal represents the normal ISP-Interface and programming is accomplished through the audio jack.

“Apps can easily be shared by sound or simply be embedded into a video. In addition, there is no mobile device without a headphone output,” the Maker adds.

Typically speaking, the Sparrow is an uber mini PCB with an ATtiny13 MCU and a comparator LM339; however, once a Maker understands its inner workings, a majority of the solution can be built from scratch. This can be done by employing materials such as a wooden board with a few thumb tacks to hold the parts together, an old mobile phone battery, a little 6V bulb and a power switch from an old toy. Beyond that, the rest of the components could be found on any engineer’s workbench — four transistors BC548A, two LEDs, two momentary switches and a few resistors and capacitors. The most expensive piece, Baum jokes, is the $1 ATtiny13.

Interested in creating one of your own? The Maker provides a detailed breakdown of the build on his Hackaday.io page here.

Spreading holiday cheer with an ATtiny13 and SPI Flash

Those who fail to believe big things can come in small packages have surely never experimented with Atmel’s versatile tinyAVR family. While we’ve seen plenty of Makers turn to the stalwart MCU lineup to bring their ideas to life, none may possess as much holiday cheer as Vinod’s latest project — which was brought to our attention by our friends at Hackaday. 

Using an ATtiny13 with a 512KB SPI Flash, Vinod created an audio player capable of playing an 8K mono WAV file for roughly a minute. At first, the Maker attempted opening up an inexpensive camera pen, but unfortunately, the PCB inside was damaged beyond repair. This left him with a 4Mbit SPI Flash chip.

“This was obviously the time to investigate what could be done with a small microcontroller and a huge amount of Flash, and the ATtiny13 audio player was born,” Hackaday’s Brian Benchoff notes.

“All together 8 pins are required. But the controller have only 5 GPIOs,” Vinod reveals.

The circuit uses one PWM for audio out, and reads audio directly from the Flash chip. In addition to that, four SPI pins were dedicated for interfacing with the Flash memory, while two others for UART communication for song updates. There’s also a switch to choose between play and record.

Impressed by the Maker’s Christmas jingle? You can find a detailed log of the build here, while watch it in action below.

Tinusaur dev board packs an ATtiny85 MCU

The Tinusaur — powered by an ATtiny85 MCU — is a simple, inexpensive and quick-start platform targeted at both Makers and developers alike.

“The Tinusaur is a minimal microcontroller hardware configuration based on Atmel’s AVR ATtiny family of products, and more specifically, those with DIP-8 case such as ATtiny25/ATtiny45/ATtiny85, ATtiny13 as well as their variations,” project creator Neven Boyanov explained in a recent Hackster.io post.

Aside from the ATtiny85, additional key platform specs include:

• DIP-8 socket
• H1 header
• H2 header
• 
ISP header
• 
Reset button
• Power header
• Battery header
• Battery jumper
• C1 capacitor
• C2 capacitor
• C2 capacitor
• R1 resistor
• 
Battery holder
• 3V battery

“All the components are easy to find, and of course, cheap. Only the minimum required components should be part of the circuit.”

In addition, the two-row headers H1 and H2 can be used as a breadboard, or to facilitate the placement of a shield. Tinusaur also includes an optional mount for a button cell battery on the bottom and a jumper to toggle the unit on or off.

On the software side, the board offers cross-platform support, as well as compatibility with the official Arduino IDE.

According to Boyanov, the goal of the Tinusaur project is to offer a simple, cheap and accessible quick-start platform for everyone interested in learning and making things. Sound like you? You can check out the project’s official page and its Hackster.io post here.

Domo arigato, ATtiny13 drives Mr. Roboto!

When it comes to Halloween, of course parents can head on down to their nearest party store to find a Disney or superhero costume; however, many find it much more enjoyable (and cost-effective) to create their own homebrewed getups. After his son decided to be a robot for the long-awaited evening of trick-or-treating, a Maker by the name of Michael did just that and built one in its entirety.

Sure, a little gray spray paint and a dryer vent hose makes for a decent costume, but adding some cool electronics certainly takes it to the next level! Subsequently, Michael turned to an Atmel ATtiny13 MCU to drive a pair of 74HC595 shift registers that light up LEDs randomly.

 

The 30-odd lines of coding utilize the random() function to shift high or low values to the shift registers. After a brief pause, the cycle continues and a new pattern of LEDs light up. Another perk? The electronics embedded within the robot can easily be transferred to another theme… think Buzz Lightyear! The possibilities span from infinity to beyond!

Check out the video of Michael’s intergalactic robot son below…

Interested in a DIY costume of your own for this weekend’s festivities? Head over to the full project page here.

 

Create a twinkling hack-o-lantern for Halloween

Are you ready for Halloween? Are you queuing up some old Misfits MP3s, watching The Crow and breaking out those twinkling jack-o-lanterns for All Hallows’ Eve? Don’t want to use traditional wax candles or buy a jack-o-lantern light? Well, you can always do what Maker Johannes Bauer did and code your very own pseudo-random flickering LED.

In order to accomplish this feat, the Maker only required a few components: four slightly depleted AA batteries, a super bright LED, 680 ohm resistor and a custom code on an 8-pin ATtiny13 MCU.

Essentially, Bauer used avr-gcc to compile, package his code and build scripts for download. As expected, the hex file can be flashed over to the chip using avrdude or AVR Studio.

A fan of carving pumpkins? Have a few tinyAVRs laying around? Go ahead and create your own ‘hack’-a-lantern!

ATtiny13 MCU powers DIY digital dice kit

A new Atmel-powered DIY digital dice kit recently surfaced on eBay. Designed and sold by eBay member “applemount,” the DIY digital dice kit features Atmel’s ATtiny13 MCU, front and center.

Aside from the ATtiny13, additional key components include:

• 1 – Lead-free professionally printed circuit board (2″x2″)
• 7 – Red LED’s
• 1 – Battery holder
• 1 – Button switch
• 1 – CR2032 battery (included)

“Push a button and the die will display a random number from 1 to 6 just like a dice! [The kits are] great for board games. [Plus], you get a free CR2032 battery with each kit!” applemount wrote in a description posted on eBay.

“[The kit] uses advanced on-board entropy collection to generate real random numbers. Soldering is required, [although] each part is clearly labeled on the printed circuit board for easy assembly.”

Interested? Step-by-step assembly instructions are available on Instructables here, while the DIY kit can be purchased for US $12 here.