Arduino – LED logarithmic fade

Yet another Arduino LED fade effect. Similar to Arduino – LED linear fade. However, this one is using logarithmic scale for the delay time. It gives a nice “breathing” LED light effect. With properly adjusted settings it can look like a sleep LED effect in a macbook. This example Arduino project lights the basic LED connected in series with … Read more

Arduino – LED linear fade

This article explains how to make an example Arduino project that lights the basic LED (connected in series with resistor to pin 11) using linear fade effect. To build a nice fade effect you need to know how to change the LED brightness, first. The complete code is also on GitHub, here. Linear Fade effect changes the LED brightness … Read more

ATtiny13 – 8bit mono class D amplifier

I always wonder whether it is possible to make an amplifier of class D on ATtiny13 or not. Some time ago I found George Gardner’s project based on ATtiny85 – TinyD. It was a sign to start challenging it with ATtiny13. It took me a few hours but finally I made it! The code is very short and useses a … Read more

ATtiny13 – hardware PWM

This article shows how to make an ATtiny13 to generate hardware PWM (Pulse Width Modulation) signal. The example code uses timer in Fast PWM mode (WGM02:0 = 3, see manual section 11.7.3). In this mode, by setting the COM0A1:0 bits to one, the compare unit allows generation of PWM waveforms on the AC0A pin (PB0) with duty resolution 0..255. The presented example … Read more

ATtiny13 – two tone alarm

This is a simple and easy to build two-tone alarm that uses ATtiny13 to produce sound effects. Note that with little modifications the project can be easily utilized for many applications, in circuits where a double tone alarm may be required. Project’s code has been designed to make possible extend a list of two-tone sound … Read more

ATtiny13 – dance lights with DFT

This experimental project shows how to use ATtiny13 to synchronize live music and lights with only a few additional components required. Project uses single ADC (Analog to Digital Converter) channel for signal acquisition and some DSP (Digital Signal Processing) calculations that in real-time separate three frequency bands and make the LEDs dance in sync with the … Read more

ATtiny13 – tone generator

There is a set of projects that require some kind of audio output. For example a simple alarm bell. This project shows how we can produce different kinds of audio effects by just using an AVR MCU and a speaker/buzzer.  We will use 8-bit Timer, PWM technique and some pre-calculations to generate right sounds. Tu … Read more

ATtiny13 – LED fading with delay function (Software PWM)

This project shows how to simply Fade-In and Fade-Out a LED by using delay function to control pulse width what is sometimes called Software PWM (Pulse Width Modulation). In our circuit a LED is connected to PB0 and it is made to Fade the LED In and Out alternately. The code is on Github, click … Read more