PWM Output on the ATtiny85

The next step in the Bluebell project is a way to provide notifications. We can control the device remotely using Bluetooth and now we need to make it display the data sent to it in an easily noticeable format. I'm going to use an RGB LED for this - it…

Using the HC-05 Bluetooth Breakout

In my previous post I described the implementation of a two pin, interrupt driven serial interface for the ATtiny - in this post I'll describe how to configure and use a HC-05 Bluetooth breakout board with that interface so you can remotely control any ATtiny based circuit. The HC-05 Bluetooth…

A Software UART for the ATtiny85

I've recently started work on a small project to provide visual notifications from a PC over a Bluetooth connection. I mentioned it on G+ a little while ago, it's essentially a minimalist version of this product. I started working on a post describing the work I was doing but it…

Bootloaders and Bricked AVRs

The last project based around an ATtiny85 was pretty successful, I'm impressed with what you can squeeze out of the chips and I have a few more smaller projects that they would be perfect for as well. One of the more frustrating aspects was having to physically move the chip…

An ATtiny85 Based Safety Light

This project is a simple presence sensing night light for doors, stairs and other areas which could be dangerous or difficult to navigate in low lighting conditions. It is built around an ATtiny85 microcontroller and uses the head from a cheap LED torch as the lighting element. The ambient lighting…

Conserving Memory on an AVR

Both the ATtiny and ATmega CPU's have a very limited amount of RAM (512 bytes for the ATtiny45/85 and 1K for the ATmega8/168) and it's easy to hit the limit without some careful programming. I've been working on a project based around an ATtiny85 that barely fits into…