This LCD message display can show text with large characters on an 20*4 LCD module. The display can show five characters at a time. Each characters is build from twelve characters of the display module. The text on the display can be read from up to ten meters distance.

 The data to build each character is stored in an external 24C32 serial EEPROM which has 4096 bytes of memory. The characters that can be shown on the display are: A to Z and 0 to 9. There are in total 35 characters so we need 35*12 bytes = 420 bytes. The text is also stored in the EEPROM.

It is also possible to show the time and temperature on the display.

To show the temperature you need to connect the LCD Thermometer DS1621 or the LCD Thermometer TCN75 to the microcontroller.

 Schematic and PCB Layout

The LCD module has to be connected to PORTB of a ATMega8 microcontroller.On the LCD@AVR you can see how tho connect an LCD module to a AVR microcontroller, or you can use the LCD adapter board that i have made for this project, you can see the schematic and the board on top of this page. In this way you can easily connect the LCD module for example to the STK500 or the AT2313 project board.

LCD_Switch_board.jpg

 

LCD_Switch_board_brd.jpg

Software

The code for the project is written in the BASCOM program language.

The text on the LCD message display can be changed via the PC's RS232 port.(under construction)

Download the program code below

lcd_message_display.bas