Tag Archives: ATtiny45

Build a rhythm LED lighting effect box

Get the party started with this ATtiny45-based LED music box.

If you’d like to measure sound for an interactive display, Ardumotive has you covered with a tutorial about how to “make your own music rhythm LED lighting effect box” with an ATtiny45.


One caveat to this method is that, according to the article, “It’s not the correct way to analyze sound signals, but it will flash LEDs in music rhythm.” In other words, it may not be appropriate for laboratory work or OSHA testing, but should be great for your next party!

The build itself is quite simple, and pipes analog audio data into the ATtiny45 via a 3.5mm audio jack. The voltage from this input is read by the chip, and outputs from zero to three LEDs based on the voltage level. While the circuit is based an tinyAVR MCU, it should also work on a standard Arduino development board, like the ubiquitous Uno.

Although this is an interesting experiment as a breadboard display, author Vasilakis Michalis decided to make it a little more interesting with simple three-segment light diffusing fixture, made with plexiglass and wood. Check it out in action in the video below!

For another excellent project from Ardumotive, why not check out this excellent plotter made from old optical drives?

Maker creates a life-size replica of Han Solo

Baltimore-based Maker Todd Blatt recently devised a life-size replica of Han Solo in Carbonite.

Star Wars Day never seems to have a shortage of innovative projects paying homage to the epic space saga. As impressive as many of those may be, one in particular had caught our attention. That’s because Baltimore-based Maker Todd Blatt recently crafted a life-size replica of Han Solo in Carbonite, designed to match the version that appeared The Empire Strikes Back and Return of the Jedi. From laser cutting to Bondo sculpting, the Maker employed a number of tools found throughout his Baltimore Node hackerspace.


That Maker studio, however, is about to relocate to a new building and won’t be able to take the 1:1 Han Solo replica along with them. Blatt explains that it had been a commissioned project, and did not want to have to go through the daunting task of moving it time and time again.

“In the movies themselves, there aren’t very many shots of the frozen figure, and only two props are in existence in the Lucasfilm archives,” Technical.ly’s Stephen Babcock writes. “Blatt was buoyed early on after finding that he didn’t have to recreate the images of a trapped Harrison Ford. In 1996, a company called Illusive Concepts was licensed by the Star Wars empire to produce replicas.”

In order to construct the prop from a galaxy far, far away, the Maker tracked down its necessary body parts in rubber form, which he then assembled with the help of Bondo. Furthermore, Blatt found the original costume’s accurate dimensions that he used to recreate some of the pieces via 3D scans and AutoCAD, while acquiring its other components from an old record player and a camera viewfinder.

“But the power to recreate things digitally is insignificant next to the power of 1970s prop makers who were just using found objects that happened to be lying around the studio,” Babcock adds. “Those studios aren’t much different from Makerspaces like the Node, with lots of stuff lying around that gets turned into something else. Prop makers often don’t even remember what they used. In the case of Star Wars, it just so happened that what is later seen on the screen became a cultural touchstone.”


Combining his inner Star Wars spirit with his Maker tenacity, Blatt was able to track down a Volvo 343 turn signal indicator, and make a mold to easily reproduce it. The other side features panels with LED lights, programmed through an Arduino that enables the lights to blink in a precise pattern. This code was written on the bottom panel, comprised of eight LED lights driven by an ATtiny45/85.

While Blatt has done his best, he tells Technical.ly that he realizes that the project can never be a truly perfect replica. Nevertheless, it was still pretty awesome!

This shivering bracelet explores time

Created by Skrekkøgle (Theo Tveterås and Lars Marcus Vedeler), Durr is officially described a “shivering” unisex bracelet designed to help humans question their conventional understanding of time. 


The extremely minimalist, 3D-printed wearable literally shivers every five minutes, creating a haptic rhythm for wearers to notice the changing tempo of time and alter their perception of it as it passes by.

Adorn this wearable to your wrist and you will surely begin reinterpreting how long it takes to hitch a ride on public transit, wait in line at Starbucks, or even how long it takes to finish that leisurely latte.


Each bracelet is unique as the casings are handmade and the vibration varies slightly due to the motors’ inherent variances. The aluminum and leather surface also varies from piece to piece. In addition, the ‘timepiece’ component of the Durr is rather nondescript for a watch, which is perhaps why its creators have aptly dubbed the wearable a bracelet instead. With no need to keep track of the hours, designers Tveterås and Vedeler decided to forgo the clock face altogether, rather implementing a solid, sandblasted anodized aluminum body.

The design of the bracelet was facilitated by an [Atmel poweredMakerBot 3D printer, which helped the duo manufacture both the durable enclosure and friction-fasteners. On the hardware side, Durr was prototyped using an Arduino board and sketch, with its earliest versions powered by an ATtiny45 MCU and a single (replaceable) CR2032 battery that lasts up to two months.

After some further iterations with the internal components, the next task was to use their multiple 3D print iterations to help find the ideal housing size to fit their final, fully-functioning concept — which was later built around the Norwegian Gecko 32-bit MCU. For the minimalist ‘bracelet’ strap, the duo chose a sturdy and high-quality Spanish leather.

While Skrekkøgle says Durr was an “internal experiment” to try and gauge public interest in the project, having only 50 units made as part of a limited alpha run, today the Durr is now readily available in Smog, Salmon, Asphalt, and Pistachio colors.


Interested in learning more about the Durr? The wishing to get a better sense of time can check out the project’s official page here.

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.

Celebrating Pong’s anniversary Maker style

November 29, 1972: A day that will forever hold a place in the heart of all video gamers. It was the day in which Atari Corporation announced Pong, one of the first video games to reach mainstream popularity in both homes and arcades everywhere. In the simulated table tennis game, players were represented by paddles that could move up and down to try to deflect a ball, all while keeping it from passing into their goal. Despite its simplistic two-dimensional graphics, Pong started a craze. A craze that still exists today.


And, what better way to honor the iconic game originally designed by Nolan Bushnell and Ted Dabney than with a set of Pong-inspired, Atmel powered Maker projects?

While it may be 2014 and Pong obviously pales in comparison to games like Crysis or CoD, some of us are clearly more prone to nostalgia than others, including James Bruce of MakeUseOf, who recently penned a detailed guide on how to recreate the retro console using an Arduino board.


“I won’t lie – it’s unlikely your daughter will be giving up her Nintendo DS, and this isn’t going to provide hours of fun for the whole family – but it is an awesome and easy project to improve your Arduino coding,” Bruce writes.

Essential ingredients for this retro masterpiece?

  • 470 ohm resistor x1
  • 1k ohm resistor x1
  • 10k ohm Potentiometer (twiddly variable resistor) x2
  • Arduino x1 (any version)
  • RCA plug x1 (if you have more than one, you can hook up sound too. One for the video is a bare minimum)
  • Pushbutton switch x1
  • 10k ohm resistor x1

Oh, and yes, you’ll also have to download the TV Out Arduino library (TVoutBeta1.zip), subsequently placing all resulting folders in your /arduino/libraries directory.

Now, this project probably isn’t for the faint-hearted, as you will definitely need to break out the soldering gun for the 470 ohm and 1k ohm resistors – which are to be soldered to the center signal line of an RCA plug.


Meanwhile, others even wear their love for the game on their sleeve — or the front of their shirt at least. A young Maker by the name of Spencer recently shared an Instructable detailing the creation of a flexible 14 x 15 pixel, Pong playing garment.


After a year’s worth of hard work, Spencer finally had the chance to adorn the wearable at a few Halloween parties back in October where it was (understandably) a big hit.

The Maker created a screen using a series of RGB LED strips, soldered together into a large flexible panel of 14 x 15 full color pixels. In addition, an Arduino Mega (ATmega1280) serves as the brains of the game, along with a cleverly designed controller using a slide-potentiometer and single button. To play back, the computer AI uses about 15 lines of code.

Oh, and yes, Spencer made the pong project removable (the batteries and the ‘Magic Box’ go into a pocket) so the shirt can be washed after it is shown off.


Then, there is Maker Fernando Vicente who revealed how easy it is to transform an ATtiny45 MCU into a fully-functional Pong game. The design was accomplished by connecting a set of RGBs to a PBo. For storing purposes, Vicente utilized fifteen registers throughout the project to achieve a horizontal resolution of 120 x 96, giving the screen a more square appearance.


“There are also other parts of the code that might be of interest. For example, I’ve use LFSR to add some pseudo-random variables to the ball direction and the paddle ‘computer’ movements,” the Maker explains.

Next, Onur Avun recreated a new rendition to the classical game on an Arduino Uno (ATmega328) using a PCD8544 LCD screen — more commonly known as the Nokia 5110 screen. Player bars are controlled by a potentiometer for each player, meaning if you want the bar to go left, just turn the potentiometer left.


Lastly, our friends over at Evil Mad Scientists decided to pay homage to the pop sensation by building a real-life tabletop Pong game. Driven by an ATmega168, the Makers devised a project which combined the awesomeness of ping-pong, foosball and pinball. In the recreation, two players each have a single knob responsible for controlling the position of a paddle along a short track.

Using the paddles, the ball is bounced back and forth, with each player attempting not to miss the ball. The paddle surfaces are curved, so that the ball reflects in various directions depending on the position of impact. The paddles are also powered, thereby enabling the ball to maintain a fairly constant speed between the two sides, gradually increasing as the game goes on.


“The playfield is level and has a dotted line down the middle, and the scores are displayed on either side of that line. There are top and bottom walls of the playfield that the ball can bounce off of. Sounds possible, right? So we built it. We documented the build with (a heck of a lot of) photos, which are available in this Flickr set,” EMSL notes.

Creating an inexpensive and tiny AVR programmer

A young Maker by the name of Ian M. recently decided to see just how inexpensively he could build an AVR ISP programmer. Based on the vusbtiny AVR programmer design, Ian’s creation omits two resisters and two diodes, leaving just four components.


“Turns out you don’t need two of the resistors, or the diode. My schematics are released into the public domain, and the original code stays under its original license,” the Maker writes.

The remaining parts included a 1.5k resistor, a small capacitor, a USB connector, a six pin header, and of course, an Atmel ATtiny45. Ian does warn that the design may not be entirely up to USB specifications, but it is functional.


Want to learn more about this tiny, tiny AVR programmer? You can read all about his build 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!

ATtiny45 drives this optical theremin

A Maker by the name of Derek recently created an optical theremin to illustrate the types of devices typically found in hacker and Maker spaces.

As HackADay’s Rick Osgood reports, the solderless Noise-o-Tron kit is powered by Atmel’s ATtiny45 microcontroller (MCU).

“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,” writes Osgood.

“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.”

According to Osgood, Derek designed a simple PCB out of acrylic, with laser cut holes to fit the components and leads twisted together.

“I learned a lot with this project and I think some other people did too. I had kids as young as 5 assemble these boards with guidance, some of them with surprisingly little help,” notes Derek.

“Everyone seemed to like them and I ran out of components for kits. I’m calling it a huge success and I hope that this project is replicated and taken to Maker Faires, expos and ‘learn electronics’ nights.”

Interested in learning more about the solderless Noise-o-Tron kit? You can check out Derek’s blog post here and the relevant Github files here.

Generating random numbers with an ATtiny45

A HackADay forum member by the name of Karl wanted a hardware-based random number generator. His two primary criteria? Keeping costs low and ensuring sufficient generation of arbitrary numbers.

The solution? Atmel’s ATtiny45 microcontroller (MCU), paired with a USB/serial converter, three wires and a DIP socket.

“Some projects either require expensive parts (geiger tube), are quite big (lava lamp), or are not random enough. Also most of the projects require some soldering experience, which can be a problem for newbies,” Karl explained in a HackADay forum post.

“I was not happy with the options I found. Luckily I stumbled upon the Entropy library for AVR’s. I checked the results from authors’s web site. I also did a few tests on my own by creating a 1mb sample of random data. I was pleased with the quality of the random numbers.”

As HackADay’s Brian Benchoff explains, the AVRentropy uses the watchdog timer’s jitter in AVR microcontrollers to provide cryptographically secure random numbers.

“Setting up the circuit was easy – an ATtiny45 microcontroller was connected to an [inexpensive] USB to serial converter. Three wires, and the circuit is complete. The code was simple as well; it’s just a call to initialize the entropy and write the bits to the serial port,” Benchoff added.

“There are a few drawbacks to this build. Because the entropy library must wait until enough entropy is gathered, it can only produce about two 32-bit numbers per second. That’s all Karl needed for his application, though, and with an enclosure made from a wine cork and marble, he has the prettiest and smallest random number generator around.”

Interested in learning more about a hardware-based platform to generate numbers based with an ATtiny45? You can check out the original forum post here.

Designing an ATtiny45-based business card

A Maker by the name of Simon Bach has created a slick circuit board business card powered by Atmel’s versatile ATtiny45 microcontroller (MCU).

”First I designed the circuit and layout with Eagle. The actual circuit is very simple: four LEDs with resistors of 330 ohm at 4 I/O pins,” Bach wrote in a recent blog post.

“Since only one input and the reset pin on the Attiny is left, I decided to attach the four buttons for input through multiple resistors to an A/D input. Depending on which push-button/resistor combination is pressed, a different value between 0 and 1023 can be read on the A/D input. This value is mapped to a button in the program.”

According to Bach, the photo and contact details were created using Photoshop, with the image framed by a honeycomb pattern. Once the finished layout in Eagle was exported to a PS file, the picture and layout were merged.

“To put layouts on copper board, I use the toner transfer method. The layout is printed by a laser printer and melted with a laminator onto the board,” he explained.

“In order to obtain useful results, the choice of paper on which the layout is printed is crucial. The toner should not be absorbed too much by the paper, but adhere enough to the paper so that nothing smears.”

Before the layout was laminated, Bach cleaned the board and degreased it with acetone. He then proceeded with the transfer, using a fuser salvaged from an old laser printer.

“The board is etched in a sodium persulfate solution, which is heated to about 40 degrees Celsius. The process takes about 20 minutes, swirling the solution supports the etching process,” he continued. “In order to avoid etching away the fine copper traces, I took the card out of the etching bath after the actual circuit was etched completely.”

In terms of programming, Bach connected the Atmel MCU to an Arduino Duemilanove (ATmega168) with matching ISP sketch.

“This little game was also created with the Arduino IDE. Appropriate board settings for ATtiny µC have to be loaded into Arduino IDE before they work with the IDE,” he concluded. 

”The required A/D values for the keys were recorded via an analog input of the Arduino and entered into the final program. Since the A / D values vary slightly by decreasing battery voltage, an upper and lower limit for the respective key has to be specified.”

Interested in learning more about the Atmel-powered ATtiny45-powered business card? You can check out the project’s official page here.