Tag Archives: Decision Box

This ATtiny85 box will make decisions of you

Can’t make up your mind? Then you may want to make this box.

After frequently finding himself struggling with everyday decisions, Victor8o5 chose to create a pint-sized box that would make them for him. Instead of toiling over making the right choice, the clever ATtiny85 powered tool would spit out a simple ‘yes’ or ’no’ answer. Following the incredible popularity of his original project (60K views on Instructables and counting), the Maker designed the next iteration of his device — this time with more commonly available materials so everyone could build their own.


Whereas the first version consisted of a small wooden cube with a single cathode red-green LED, the shell of the latest model features two perforated boards stacked together, joined by pin headers and connectors, along with three LED lights. While the circuitry itself is fairly straightforward, the Maker advises that assembling it unison in two different planes can be a bit tricky.

“This circuit runs on 1mA when in idle and around 5-6mA when using the LEDs, so assuming the coin battery has a capacity of 200mAh, it should run for a week before draining the battery in case its left on,” Victor notes.


“For the main switch, I used a pair of pin headers and a bridge connector from a computer, you can use a small though-hole switch or even a tilt switch,” he adds.

Victor programmed the cube to include three possible outcomes each represented by a different color. Green, yes. Red, no. Yellow, maybe. However, he does note that the latter can be undone by easily changing the code and removing the LED. The probabilities can also be modified, for example, by setting both red and green to 40% while keeping the yellow at 20%.


“To do this, simply expand the range of the elements in the random function and include them in the statements as shown as shown in the picture,” he concludes. “The random function will output anything from 0 to the second variable minus 1, meaning that if we introduce 3, the results can be 0, 1, or 2 (red, yellow, green). By introducing 5 as the second variable we can get 0, 1, 2, 3 or 4. We can use an ‘if’ function so 0 or 1 are recognized as red (40% chance), 2 yellow (20% chance) and 3 or 4 green (40% chance).”

Well, one thing is for certain: Though he may struggle with everyday decisions, when it comes to choosing awesome projects, he seems to have that under control. Think you may want a box of your own to stop the hemming and hawing the next time you’re in Starbucks, head over to the project’s official page here.

Making decisions with ATtiny85

A Maker by the name Vicor8o5 was frequently finding himself struggling with important decisions. Instead of toiling over making the right choice, he chose to turn to technology to help him out. He devised this clever tool to aid him in the daily decision making process.


To fix his issue, Victor8o5 set out to make the Decision Box, which makes as its name suggests, makes decisions for you by either showing a green or a red light. Outlined in a recent Instructables post, the Maker started with a small wooden cube and hollowed out a space for the technological components in the center. He wired his circuit, including a red/green light and an ATtiny85.


The code uploaded to the ATtiny85 uses a random function to produce either a red or green light. After running a test of 80 random decisions, Victor8o5 ended up with 44 reds and 36 greens. Even though that sounds like an elementary school math problem, it’s a solid distribution for this handy device!

The next time you find yourself stuck on ordering grande or venti coffee at Starbucks, head over to his original Instructables post to learn how you can make your own device.