ATtiny85 MCU - some tests and example apps + I2C and LCD libraries

LED blink firmware putting the MCU into power-down state between the LED changes.

A simple demonstration of PWM LED charlieplexing.

MQ6 readout and a progress bar on a LCD.

MQ6 readout and a progress bar on a LCD.

A simple circuit making different noises at random intervals when left in the dark. The sounds/noises are:

• snd/snd_cricket.c - cricket chirp
• snd/snd_droplet.c - leaking faucet
• snd/snd_insect.c - buzzing insect
• snd/snd_scifi.c - sci-fi/robot sounds
• snd/snd_water.c - running water
• snd/snd_whisper.c - scary whispers

Connections are simple:

• PB1/PB4 - piezo buzzer
• PB2 - LDR (light-dependent resistor) to VCC and a 10k resistor to GND

Simple Geiger Counter based on ATtinyx5 MCU. This is more of a Geiger alarm. Tracks the radiation dose internally, but only signals two alarm levels on a two-color LED and produces sound clicks if the alarm level is breached. It's also designed to be very low-power (battery life test ongoing). No schematic yet, but here is a block diagram and a veroboard-style PCB (made with VeroRoute).

The BJT transistor can also be MPSA42. The buzzer MOSFET should preferably logic level.

The firmware is designed as a simple and lightweight cooperative scheduler maintaining in every state the lowest power level possible:

cmake -DCMAKE_BUILD_TYPE=Release -DAVR_MCU=attiny85 \
      -DAVR_PROGRAMMER=avrisp -DAVR_PROGRAMMER_PORT=/dev/ttyACM0 \
      -DMCU_FREQ=8000000 -DCMAKE_TOOLCHAIN_FILE=../toolchain-avr-gcc.make ..

make -j

If you have questions, contact Mariusz Ryndzionek at:

[email protected]