Category Archives: AVR Projects


Minimalist ATtiny85 wrist watch

David Johnson-Davies’ minimalist ATtiny85 wrist watch displays time using 12 LEDs that are arranged in a circle like a watch dial. A push button, installed on the top side of the PCB, needs to be pressed to see time. The watch shows the hour by lighting up an LED and minute by flashing another LED. The minute resolution is 5 min. To show the time you press the button on the watch face, and the time is then displayed for four seconds. It lights one LED to show the hour, and flashes another LED to show the minutes to the nearest

Read more

BuzzWatch: A personal tactile reminder

BuzzWatch is a wearable tactile reminder device that can be programmed to vibrate at constant or random intervals notifying the wearer about the passage of time, as well as prompting them to think about what they are doing, and if they need to be somewhere else at the moment. The device uses the Atmel ATTiny13A MCU as its brain, with a thumbwheel potentiometer for setting the time interval of the reminder. A tiny vibrating motor works as a buzzer in the device. The whole electronics fit into a 3D printed ABS case with dimensions of 30x30x9mm. BuzzWatch runs off a 1225 lithium coin cell.

Read more

USB media volume control

This simple ATTiny 2313-based USB media controller design from Rupert Hirst lets you add an external volume and mute control to your PC. It uses V-USB, a software implementation of a USB 1.1 compliant for lower end AVR microcontrollers that do not natively support USB. I chose to go with the Zener 3V6 (3.6volts) diode approach to keep the Micro power rails at 5volts as I have in most of my experiments.The specification of the 3V6 type Zener is very important to the design, the total power consumption of the part must be no more than 500mw (0.5w)! due to extra capacitance on the USB -DATA and +DATA

Read more

DIY Buck-Boost converter

A buck-boost (also known as step-down and step-up) converter is a type of DC-to-DC converter that combines the principles of the buck and boost switched mode power supplies in a single circuit. What this means is the input voltage could be either higher or lower than the desired output voltage. The Buck-boost converter is very useful in battery-powered systems, where the battery voltage can vary quite a bit depending upon its charge condition and usage, to derive a stable DC supply for an electronics circuit. GreatScott‘s new Youtube video tutorial explains the basics of Buck-Boost converters and shows how to build

Read more

ATtiny keychain game console

This tiny keychain game console is pretty neat and is based on ATtiny85 and and a SSD1306-driven OLED screen. The author has also shared the code for the UFO Escape game for this console. I finally had some free time to make something fun and decided to write a new game for the Attiny85 ssd1306 keychain.  I reused the sleep, display and interrupts code from the “Breakout” game I created a while ago. This time I wanted a more addictive game. The game had to be playable using just the two buttons. I thought a racing game might be a good

Read more
« Older Entries