In this session we are going to design an 8×8 LED display with 8×8 LED matrix and ATmega8 microcontroller, which can show alphabets or names.
A 8×8 LED matrix contains 64 LED (Light Emitting Diodes) which are arranged in the form of a matrix, hence the name LED matrix. These matrixes can be made by circuiting 64 LEDs; however that process is time consuming. Now a day they are available in compact forms as shown in figure. These compact modules are available in different sizes and many colors. One can choose them on convenience.
The cost of module is same as cost of 64 LED, so for a hobbyist this is easiest to work on. The PIN configuration of the module is as shown in figure. The PINs should be number exactly as shown in picture for avoiding errors. We will discuss the internal circuit configuration of module in detail in description.
Hardware: ATMEGA8, Power supply (5v), AVR-ISP PROGRAMMER, 100 uF capacitor(connected across power supply), 1KΩ resistor(8 pieces).
Software: Atmel studio 6.1, progisp or flash magic.
Circuit Diagram and Working
The connections which are done between ATMEGA8 and LED matrix module is shown in below figure.
PORTD, PIN0 ——————PIN13 of LED module
PORTD, PIN1 ——————PIN03 of LED module
PORTD, PIN2 ——————PIN04 of LED module
PORTD, PIN3 ——————PIN10 of LED module
PORTD, PIN4 ——————PIN06 of LED module
PORTD, PIN5 ——————PIN11 of LED module
PORTD, PIN6 ——————PIN15 of LED module
PORTD, PIN7 ——————PIN16 of LED module
PORTB, PIN0 ——————PIN09 of LED module
PORTB, PIN1 ——————PIN14 of LED module
PORTB, PIN2 ——————PIN08 of LED module
PORTB, PIN3 ——————PIN12 of LED module
PORTC, PIN0 ——————PIN01 of LED module
PORTC, PIN1 ——————PIN07 of LED module
PORTC, PIN2 ——————PIN02 of LED module
PORTC, PIN3 ——————PIN05of LED module
For more detail: 8×8 LED Matrix Interfacing with AVR Microcontroller