AVR Based Binary Clock on an Old Harddisk

Figure 1 

The project utilizes a defective hard drive as the case for the clock together with the Atmel AT90S2313 to produce a binary clock device.

The design consists of two 6-bit registers, one for seconds and minutes and one 5-bit register for hours, instead of using 6 binary registers for a 6-digit display. This makes it easier to read and looks more elegant and different. The HD platters on the motor are kept while some SMT LEDs were mounted in order to create a radial matrix display to produce a persistence of vision display.

A 20-pin, 2kb flash-based RISC controller with built-in UART Atmel AT90S2323 microcontroller is used on this project since it has plenty of I/O for the task and small in size. C is used to write the code and compiled with the AVRGCC compiler.

Three small boards were built to go on the back of the HDD case, onto which the LEDs are mounted, and one board for each register. The boards contain 5 or 6 LEDs, a 6-pin single row 90° header, a Darlington PNP transistor, and a base resistor. the header pins are for power, enable, and LED ground wires.

Rest of the project