LCD controller

The DE2-115 includes a 16x2 character LCD display. The LCD controller handles the low-level details of communicating with the LCD display. The LCD controller is implemented in lcd.v.

lcd_command and lcd_response implement the standard I/O protocol. The command parameters are lcd_x, lcd_y, and lcd_ascii. lcd_ascii specifies the ASCII value of the character to be written, and lcd_x and lcd_y specify the (x,y) location of the character to be written. The coordinate of the upper left character is (0,0); the coordinate of the lower right character is (15,1).

ase100 simulates the LCD controller accurately enough for you to test your device driver and to run assembly-language programs.

Lab 7 task

Write a device driver for the LCD controller that a program can call to write a character to a specified position on the LCD. Then, write a test program that prints a message to the LCD display. The message should be stored as an array of ASCII values, with the length of the array specified by another variable.