Tag Archives: ATtiny25

Uzebox is an open-source retro gaming console

Uzebox is an AVR-based console that brings back the days of 8-bit video games.

Do you remember reading comic books while waiting for your Amiga 500 to load the latest game, or the joy you felt when slipping in your first 8-bit Nintendo cartridge? We still do, and nostalgically recall a simpler time when many of the games and hardware were easy to use, easy to understand, and most importantly, easy to mod.


As previously reported on Bits & Pieces a few years ago, Uzebox is an open-source console that brings back the minimalist days of video games. Based solely an ATmega644 and an AD725 RGB-to-NTSC/PAL encoder, it uses a split software approach where sound mixing and video signal generation are done in real-time by background tasks, enabling games to be developed in C. They have over-clocked the CPU “slightly” from 20 to 28MHz, but at room temperature, so it’s really not a big deal. Beyond that, the system supports 256 simultaneous colors and four sound channels, and has a SD card interface from which games can be loaded from.


It was the brainchild of Alec Bourque, who created it with one goal in mind: “To be as simple as possible yet have good enough sound and graphics while leaving enough resources to implement interesting games.”

During last year’s Maker Faire, we had a chance to get our hands on the console as we hit the virtual 8-bit ice for a Blades of Steel battle — it was as if we traveled right back to the ‘90s. What’s nice is that Uzebox even uses standard NES/SNES controllers.


Unless of course, you’d prefer a keyboard. That’s because Bourque has unveiled his latest project that has been in the works  for quite some time: the Uzebox keyboard. The interface, which is based on the uber-mini ATtiny25, enables users to connect any PS/2 keyboard to the player 2 SNES port. With the use of SNES controller cord, the interface is so small that it can be easily embedded into an SNES plug or the keyboard itself.

Intrigued? You can check out all of Uzebox’s recent updates and games on its official website. Meanwhile, you can watch it in action below.

This littleBits device alerts roommates to stop hogging the bathroom

“Time’s Up” was designed to solve an age-old problem that has plagued roommates, siblings and spouses for years. 

Have you ever been in a rush to get up and out in the morning only to find one of your roommates hogging the bathroom for too long? Thanks to Makers Mu-Ti Huang, Douglas Tran and Yun Zhou, you may soon be able to use a little device that will serve as a friendly reminder for the occupiers.


The aptly-named Time’s Up system is comprised of a littleBits cloudBit, an Arduino module (ATmega32U4), an IR transmitter (ATtiny25), an MP3 player (ATmega168), an AC converter, a bright LED, as well as some wire and USB power adapter.


By using a cloudBit module, the user is able to wirelessly express their discontent to whoever is in the bathroom by pressing a button on their smartphone. This triggers the device to begin playing an annoying song to alert the person that he or she has been in there for way too long. When the song stops, the DIY system turns off the bathroom lights.

Does this situation sound all too familiar? Then you’ll want to check out the entire project on littleBits here.

This littleBits frame changes based on your gym habits

A piece of art that gets more beautiful when you “do good.” 

With the new year officially underway, it’s a safe assumption that many, if not all, of you had exercising among their resolutions. However, truth be told, actually getting up and going to the gym isn’t as easy. That’s why Maker Natasha Dzurny has created a simple mechanism in the form of a picture frame to help keep her routine going.


Aptly dubbed Smart Artthe project uses the power of littleBits cloud and Arduino (ATmega32U4) modules to know the last time she has been to the gym and how long it’s been since then. If she’s completed a workout recently, the art reveals a colorful rainbow over a beach. However, if she hasn’t exercised in three days, a storm rolls into the piece.


Using IFTTT, Dzurny set the trigger as her smartphone and entered the location of her gym. She then configured the action as the output of her littleBits cloud module. The Arduino listens for the signal from the cloud module, and begins the counter. In the event that too much time passes, the Arduino activates the servo motor (ATtiny25), thereby changing the sky’s backdrop.


Smart Art is also equipped with a button, so the Maker can trigger it manually if she happens to squeeze a workout in somewhere other than her regular gym, as well as a long LED that lights up when either trigger is activated.

Interested in a similar gadget of your own? Check out the project’s official littleBits page here to get started.

This interactive piggy bank sure beats your old ceramic one

Saving a ‘littleBit’ of money has never been so much fun. 

For as long as you can probably remember, piggy banks have been comprised of either ceramic or porcelain, and generally served as a educational device to teach the rudiments of savings to children. Often times, the only means of opening aside from the slot for inserting coins was smashing the bank with a hammer to obtain the money within. In more years years, however, those fragile pieces were gradually replaced with electronic keepsakes that were able to record the inputted amount as well as dispense the money in much easier fashion. However, were they able to interact with you as well? Most likely not.


With the advent of littleBits, we’ve seen a number of interact piggy banks emerge, but none may as impressive as this recent one from Alex Pikkert. The Dutch Maker has designed a slick money-saving machine that not only swallows your coins but thanks you for the contribution with some appropriate tunes.


How it works is relatively simple. When you slide a coin down the ramp, the coin covers a light sensor, which triggers a set of reactions. The servo module (ATtiny25) opens a door below the ramp while a DC motor-driven camera mechanism pushes the coin into a recess below. Meanwhile, an animated graphic powered by a second servo sends its appreciation for saving, as its ATmega168 based MP3 player emits a musical money track over a pair of built-in synth speaker. A nice incentive indeed!


Interested in creating your own interactive bank? Head over to the project’s official littleBits page here.

This IFTTT surfboard clock shows wave height

This simple, cloud-connected surfboard clock displays the wave height in Newport, Rhode Island.

If you’ve ever seen a surfing movie like Maverick, then you know experienced surfers will tell you that the best time to catch a wave is generally in the morning. But before doing so, they must tune-in to reports to hear about the swell. And, while most folks in New England could only dream of hitting the beach, soaking up rays and hanging ten at the moment, self-proclaimed culture hacker Zachary McCune has designed a slick cloud-connected display that reports the height of waves right from home. After all, summer isn’t that far away.


The appropriately-named Tide Machine is a simple clock-like device that uses IFTTT to collect Surfline reports and sends the data to a built-in cloudBit and servo littleBits module (ATtiny25). Aesthetically, the project is merely a small box with the numbers 1-4 and a surfboard as a dial, which provides updates on the tide heights every five minutes. Depending on the waves for that particular day, the dial will move and point to the corresponding number to indicate tide heights.

The time-lapse video below shows the build from beginning to end, while a how-to log of the Tide Machine can be found here. Surf’s up, Makers!

ButterBot is an automated buttermilk-churning machine

This littleBits contraption makes a mean glass of buttermilk.

Rather than with a cup ‘o joe, Maker Milind Sonavane kicks off every day with some freshly churned buttermilk for breakfast. As you can imagine, making buttermilk can certainly be a time consuming process, so Sonavane decided to build an automated ButterBot to simplify his morning routine.


“The Indian way of making buttermilk involves churning curd to and fro to get the fat out as butter, and leave the liquid behind as buttermilk. This is usually done with a wooden stirrer and a rope wrapped around it – tugging on either ends of the rope makes the stirrer churn the life out of the fat,” our friends at littleBits write.

The ButterBot expedites this process using an ATtiny25 powered servo motor, along with a cloudBit module to handle the time-bound automation.


“We didn’t want to get into the complexities of gearing and wanted the device have an earthy feel to it. So we got two plates of wood turned on a lathe, used one as a plate for the servo motor, the other as a holder for the churner, held the two together with a piece of laser cut acrylic and connected the motion with a piece of red twine,” Sonavane explains.


How it works is super easy. Every morning at 8am, an IFTTT recipe tells the cloudBit to activate the tinyAVR based servo which moves the rope to and fro, churning the buttermilk for 20 minutes straight. The milk then sits for five minutes as the butter rises. At 8:30, when the buttermilk is ready, another IFTTT recipe turns the ButterBot off. Once completed, Makers can add milk to the bowl and leave the curd to set for the next day.

Looking to jumpstart your morning with buttermilk? You’ll have to check out Sonavane’s entire build 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.

$19 ATtiny25 BFuse hits Tindie

Powered by Atmel’s ATtiny 25 microcontroller (MCU), BFuse is an electronic fuse designed specifically for breadboards.

According to the product’s official Tindie description, the BFuse is fast, adjustable and programmable.

“A lot of mistakes can happen during prototyping: Misplacing components, creating random shorts or simply making things wrong,” BFuse creator Kaktus explained. 

”BFuse can help saving precious components that would otherwise be damaged by such mistakes. It works like a regular fuse, only better.”

So, how exactly does the board work? Well, BFuse continuously compares the load current with the value set by the trimmer. Meaning, If an overcurrent occurs, BFuse disconnects the load by switching off a P-channel MOSFET – notifying the user by lighting a red LED. Meanwhile, a green LED confirms when the load is connected.

“Even though the fuse is designed for operations up to 1A, it can measure current up to 5A, giving you options to allow for some inrush current for capacitive loads. BFuse is powered by the same line it protects, no extra power needed,” Kaktus concluded.

“BFuse not only protects against overcurrent but it has also built-in reverse polarity protection. Moreover, it has a transient-voltage suppressor on both its input and output. BFuse was tested on a 22-Amp Statron stabilized power source for short-circuit and startup into short-circuit – it passed with flying colors.”

Aside from Atmel’s ATtiny 25 microcontroller, key technical specs include:

  • Input voltage range: 3.3–12V (absolute maximum rating 3–13V)
  • Measured current range: 5A
  • Trip current range: 50mA–1A
  • Fuse resistance: less than 100 milliohm
  • Fuse power consumption: less than 10mA
  • Dimensions: 18×36mm
  • Weight: 4.5 grams

Note: BFuse is shipped as a kit, so Makers and engineers will have to solder the pin headers: 4 pins for the power line (input/output) and 6 pins for the SPI header (to re-program BFuse).

Interested in learning more? You can check out the official BFuse Tindie page here.