Tag Archives: ATtiny85

Only a true Maker has a Christmas tree like this

Zach Burhop’s Trinket-powered piece is complete with 3D-printed ornaments and a custom LED star.

Two years later and Zach Burhop’s Christmas tree is still spreading some holiday cheer. Back in 2013, the industrial designer by day and Maker by night may have built one of the most geeked-out decorations of all-time. And with December 25th quickly approaching, we figured what better time to reminisce about the amazing tinyAVR-powered piece — complete with 3D-printed ornaments and a custom LED star.


“I was very disappointed in what you can buy — mostly just classical decorations. I saw the ornaments and had started playing around with the LEDs and thought this would be an awesome mashup,” Burhop explained.

In terms of electronics, the engineer (who happens to be a huge Adafruit fan) had some NeoPixels and Trinkets (ATtiny85) lying around. A two-meter LED strip was driven by the tiny MCU, and ran through the center of the tree, fading out through the branches. Another Trinket was tasked with controlling the 3D-printed tree topper’s animations. He also picked up an AC brick at a local thrift store, which handled all of the necessary power requirements for the 120 or so lights.


What’s more, you’ll notice that Burhop selected a white tree, which proved to be the ideal backdrop for the flickering, addressable RGBs and colorful DIY ornaments. Trust us, you’ve got to see it in action.


Light the menorah with an ATtiny85 and LEDs

Add some colorful LEDs to your Hanukkah celebration!  

The Evil Mad Scientist’s Mega Menorah 9000 is an updated take on the traditional hanukkiyah, a nine-armed Hanukkah candelabrum. But instead of candles, this DIY kit swaps out flames for ultra-bright LEDs capable of producing all kinds of colors and flickery effects.


The Mega Menorah 9000 has an Adafruit Trinket (ATtiny85) at its heart, and is powered by either USB or a 5V DC source. The device is USB programmable via the MCU’s built-in interface.

“No additional hardware is needed (other than the computer and standard USB cable), and you can use the Arduino IDE or avrdude (with some config changes). Our example code (standard firmware) is available for download and is written as an Arduino program, making use of the Lightweight WS2812 library,” EMSL writes.


When turned on, the menorah displays the correct configuration of LED “candles” (just without all that wax) for each night of Hanukkah. Every time that a user presses the “night” button or plugs it in, the ATtiny85 based candelabrum will trigger one more light than it had the previous time. The LEDs are lit up in the traditional sequence, each with a candle-like fade.

The Menorah Mega 9000 features a candle lighting sequence, which allows a user to adjust the brightness level and dim intensity, turn on/off flicker mode, as well as enhance its beauty with one of 24 built-in color combinations. And for the more elegant folks, despair not! This DIY hanukkiyah is equipped with blue/white blinky modes. To change the tone, simply press the “color” button.

“From a control standpoint, it’s awfully nice that they’re managed by just a single pin of the microcontroller, and have the built-in ICs to handle colors and dimming,” EMSL notes.


The Mega Menorah 9000 ships as a soldering kit and includes a pair of circuit boards: an oval-shaped one that holds the MCU, USB jack and control buttons, and another carved in the likeness of a menorah with nine RGB LEDs and connectors.

When completed, the accessory makes for an excellent holiday centerpiece. Measuring just 6” tall and  7.5” wide, the menorah can rest easily on any window sill, mantel or wherever else its creator desires. But perhaps one of, if not, the coolest things about this unit is that it boasts a unique “Trompe-l’œil” PCB design. Although it is actually flat, this gives the illusion of a rounded 3D surface.


Interested? Head over to Evil Mad Scientist’s official page here. In the meantime, happy holidays!

This $10 device can predict your next credit card number

MagSpoof is an ATtiny85 based device that can accurately predict your next Amex card number, disable chip-and-PIN and even spoof magnetic stripes wirelessly.

After recently losing his credit card, it wasn’t long before American Express sent Samy Kamkar a replacement. It was that moment in time that the serial hacker noticed something quite peculiar: the digits on the new card were similar to his previous ones. With a little more research, he uncovered a global pattern that would enable him to accurately predict the digits on any subsequent Amex card by knowing the preceding card’s full number.


“This means if I were to obtain your Amex card and you called it in as lost or stolen, the moment you get a new card, I know your new credit card number,” Kamkar explains. “I also know the new expiration date as the expiration date is fixed based on when the new card was requested, and you can determine if the new card has been requested by performing an auth on the existing card.”

Like many of his prior security-focused projects, this discovery yielded another opportunity to highlight a vulnerability. And so MagSpoof was born. Kamkar’s new $10 device is capable of emulating any magnetic stripe or credit card, entirely wirelessly, and storing more than 100 card numbers in various form factors. The unit works by generating an electromagnetic field that’s strong enough to reach a traditional reader’s sensor within close proximity, sending a signal that mimics the card being swiped.

“What’s incredible is that the magstripe reader requires no form of wireless receiver, NFC, or RFID — MagSpoof works wirelessly, even with standard magstripe readers. The stronger the electromagnet, the further away you can use it (a few inches in its current iteration),” he notes.


And that’s not all. MagSpoof features a button that employs his prediction algorithm. In order words, if a thief using the device finds out that the card they were trying to imitate had been cancelled, the gadget could instantly determine the victim’s next card number.

“As soon as the card gets declined, you press a button and it switches to the next number,” Kamkar tells WIRED. “It sucks for [Amex users], because they could have their new credit card stolen almost instantly.”

Aside from disabling chip-and-PIN protection (a function that he has since removed), accurately predicting expiration numbers and switching between different Amex cards (even when reported lost or stolen), MagSpoof can be employed for security research in any area that would traditionally require a magstripe, such as readers for drivers licenses, hotel room keys and automated parking lot tickets.


As you can tell, the MagSpoof’s hardware doesn’t look anything like a credit card, so a criminal couldn’t just simply hand it to a cashier or waiter without raising any red flags. However, Kamkar points out that he can use a digital credit card device like Coin to store the numbers that his system generates — a technique that would make his trickery much less noticeable.

Impressively, Kamkar built his prototype out of several off-the-shelf components. These included an ATtiny85, a 100mAh 3.7V LiPo battery, a motor driver, an LED, a capacitor, a resistor and some 24AWG magnet wire. He created a smaller version with an ATtiny10 as well. By simply pulsing the H-bridge and activating the coil of wire, the MagSpoof is capable of emulating the swipe of a card. MagSpoof is compatible with the Arduino framework and can work on traditional Arduino boards, as well as ATtiny chips.

According to the hacker, he has notified American Express of the issue and will not exploit their algorithm. Kamkar has made both MagSpoof’s source code and schematics available on GitHub, and elaborates upon his method on his page here.

[h/t WIRED via Samy Kamkar]

Are conductive temporary tattoos the future of wearables?

Time to get skintimate with Tech Tats.

Although there’s already an abundance of activity monitoring wearables on the market today, mobile development studio Chaotic Moon is exploring a new frontier in the industry. The Austin-based firm has decided to go beyond just a fitness tracker with a collection of biosensors that affix to your skin like a temporary tattoo.


In one of its uses cases, the aptly named Tech Tats consist of an ATiny85 that stores and receives body data from sensors via Bare Conductive’s Electric Paint. This combination of basic components and conductive ink come together to create a circuit that essentially turns you in a cyborg. There’s even some room for an ambient light sensor that illuminates LEDs whenever it’s dark. And unlike most wellness devices, the temporary tattoo can be worn in other places than merely the wrist — all while remaining unnoticeable. 

Tech Tats boast various applications, with health and mobile payments being two of them. For one, the biosensors can be stuck on the skin once a year instead of having to go for an annual physical, and will keep tabs on all of your vitals that the doctor would normally check for. The information can then be sent to the doctor, who will notify you only if there is an issue. This can also come in handy following surgery to better keep tabs on a patient’s progress.

According to Chaotic Moon, the temporary tattoo can read body temperature as well as sense if someone is stressed based on sweat, heart rate and hydration levels. Throw on a BLE module and data can be wirelessly transferred to an accompanying smartphone app, or uploaded through location-based low-frequency mesh networks.


Not only the medical field, but Tech Tats can find a home in banking industry, too. Instead of carrying a wallet around with all of your most personal information in your back pocket, these conductive patches can be employed to authorize payments in similar fashion to Apple Pay.

Aside from that, Chaotic Moon’s bio-wearable can even play a role in the military setting by detecting poisons in the air, pathogens in a soldier’s body or identifying when they’re injured or stressed.

Could temporary tattoos be the future of wearable technology? Time will only tell. But until then, you can watch Chaotic Moon explain their innovation in the video below!


The world’s smallest ‘most useless machine’

With the help of an ATtiny85, Maker Jeremy Cook has successfully built the world’s tiniest ‘most useless machine.’

If you’re into awesome and strange devices — and that’s a good assumption if you read this blog — chances are you’ve heard of the Useless Machine, or Leave Me Alone Box. These gadgets have a switch on top, and when it’s turned on, a “finger” extends to turn it off again. Generally this is done by an elegant circuit and a DC motor, but Maker (and frequent Atmel blogger) Jeremy Cook decided to instead cheat by using a tiny servo and microcontroller to make what he believes is the smallest “useless machine” in existence — or was before it disappeared in the void that is his garage.


To accomplish this feat, Cook soldered the incredibly tiny ATtiny85 to a coin-cell battery, a switch and a little servo motor. Pieces of MDF and polycarbonate were cut to form the body and lid of this device, and everything crudely attached together to form his “useless machine.”

When the switch is flipped, the servo is actuated to push it back into the “off” position. Though this sometimes takes more than one try, it eventually was able to accomplish its useless mission. It was definitely a shoddy prototype, but with a better mechanism, this could be a fun device to show off.


“One thing that I was proud of was using the ‘delay’ command to send a pulse to the servo used for one or two milliseconds, as explained here,” Cook writes. “This allowed for very crude pulse width modulation control with this chip. The little ATtiny doesn’t have all the features of, say, the ATmega328P used in the Arduino Uno development board, but the tiny size, and correspondingly tiny price is hard to beat for some projects!”

Interested? Head over to the Maker’s official page here, or simply watch it in action below.

Watch your mouth! This ATtiny85 can swear

This project is @$!%^& awesome! 

The first Speak & Spell was introduced back in the late 1970s. Admittedly, upon coming across a speech synthesizer like that, one of the first things any of us would do is try some profanity. Well, Maker Alec Smecher has taken that concept to heart and applied it to a simple buzzer mechanism that he recently developed. Powered by an ATtiny85, the “satisfyingly minimalist project” swears repeatedly when you connect its wires to a trio of AA batteries.


“Electronic beepers are ubiquitous — in microwaves, cars, smoke alarms, etc. You can buy them for a few dollars,” Smecher explains. “But since beeping also invokes censorship, I wanted to make an ‘un-censor’ that allows the electronic device to articulate itself properly.”

The Maker had gutted an existing electronic beeper for its plastic shell, which houses the electronics, and used an 8kHz sound sample from Google Translate’s text-to-speech synth. The sample is stored in the code and written to one of the PWM outputs of the ATtiny85 from a timing loop to directly drive the small speaker.


“If you’ve had a little bit of experience with Arduinos and want to try moving to the bare Atmel chip, you can’t go wrong with the ATtiny85. It’s just shy of magic. There’s a little bit of poking around getting the Arduino to program the ATTiny85, but overall it was simple enough and I will definitely be doing more projects using this approach,” Smecher adds.

Total cost of the build: $7. The amusement that follows: priceless. You can check out Hackaday’s writeup on the project here, as well as watch a video demonstration by clicking this link. (WARNING: Video contains foul language.)

These smart shoes will improve your morning jog

These Arduino Gemma-based sneakers will make your run more fun with less injuries! 

Like 75% of runners, Maker Lisa Kusaka is an avid jogger, but doesn’t enjoy it so much without her extensive playlist of music. One day, she noticed that certain songs seemed to suit her pace better than others, becoming a natural and entertaining pace keeper. With this in mind, RunBeat was born.


Developed while at SLEM (an international innovation and education institute for footwear located in the Netherlands), it is a smart insole that measures your running pace and generates music with the same beats per minute to match your stride. The system consists of a pressure sensor embedded into the insole beneath the ball of the foot to promote proper running form. The sensor reads the impact of each step and sends the data over to an Arduino Gemma (ATtiny85) located in the shoe’s arch.

This pace data is also transmitted to an accompanying mobile app via Bluetooth. This app then selects the tunes based on the preferred genre and the current running pace. What’s nice is that, since all of the technology is located in a 3D-printed insole and not the sneaker itself, RunBeat is compatible with just about every running shoe on the market.


On top of that, fellow SLEM classmate Chrissy Glove recently came up with an idea to improve the running experience as well. This time, instead of pairing beats to stride, the maker wanted to create a wearable device that would help improve form. Having dealt with injuries throughout her own career, she was well aware as to how imperative injury prevention is to any runner. So, she decided to develop a smart sneaker that would detect improper form in three ways: by recognizing when a runner’s gait differed from their norm, suggesting a forefoot foot strike and detecting the precise location of an injury when one strikes.


The aptly named Strike features a side lacing system to relieve pressure from the tendons on the top of the foot, while Adafruit NeoPixel lights allow for nighttime safety and easy notification. Glove attached an Velostat sensor in the heel pad to an Arduino Gemma (ATtiny85) and a piezo buzzer. These electronics, along with a battery, are all enclosed inside a 3D-printed insole.

The Maker wrote some code that would read the pressure sensor as input, and in turn produce a different effect with the LEDs and piezo buzzer accordingly. For example, when the runner strikes with their heel, they will feel a buzz to alert them so they can modify their footstrike to be more forefoot. Additionally, the shoe records the wearer’s normal foot strike pattern and stores it in its internal memory. This way, should the runner happen to stray away from his or her natural gait, they will be warned in similar fashion.


Beyond that, Glove included electrodes in the shoe that could read the nerve endings on the bottom of the runner’s foot. As a precaution should they get hurt, Strike can better determine the exact location of the injury by buzzing in a varying sequence and illuminating the red LEDs.