Dot LED matrix is great for displaying various type information including graphical, text, and animation. They usually are big enough to see from a distance and bright to be visible at day and night. Embedded-lab built LED matrix display board which uses five 8×8 LED modules that makes pretty decent 8×40 display.
The display is clocked using PIC16F1847 microcontroller. Of course MCU doesn’t have enough I/Os to drive 320 LEDs. For this a cascading shift registers 74HC595 are used. One for every matrix module column. The rows are controlled with single ULN2803 which sinks LED outputs. Messages can be sent via serial interface using 8×5 byte array totaling the 320 bits. Each bit represents weather corresponding LED is ON or OFF. Received data is stored in to EEPROM memory, so after display powerup it automatically loads saved data and starts displaying without need of computer.