LED Matrix Sensitivity to Acceleration

Overview

This acceleration based LED matrix is an n-sided dice in which several different forms of dice can be displayed.

Explanation

The project is based on an ATmega168 microcontroller and is being powered by three 1.5V small button cells. The ATmega168 is programmed using AVR-GCC and AVR-LIBC. Using a ULN2008 as a current sink and a 74LS164 as LED driver, the MCU gets connected to the matrices. A speaker from a Nokia mobile phone was also included to add fun. A perfboard is used for soldering the whole circuit where all connections were made by soldering wire-up wires. In order to protect the wire-side of the PCB from tearing apart, it was covered with Perspex. The very small accelerometer MMA7260QT comes packed as a QFN16 which was attached to a tiny perfboard using some hot glue.

Using the AVR-GCC toolchain in AVR-Studio, the whole device was programmed in C. A display-driver that go over all the roles periodically needs to be programmed while the proper bitmask is pushed to the serial shift register where the LEDs are driven. In using the dice, the number of sides of the cube is selected before tilting the cube.