I am using the 8 bit mode of an Atmel ATtiny2313 to drive the display, because the 8 bit mode seemed to be the simpelst.
I am not exactly proud of the following code, but it used to work and it is very close to the instructions from the data sheet:
#include <avr/io.h> #include <util/delay_basic.h> typedef enum { FUNCTION_SET = 0b00111000, DISPLAY_CONTROL = 0b00001111, DISPLAY_CLEAR = 0b00000001, DISPLAY_HOME = 0b00000010, ENTRY_MODE_SET = 0b00000110 } INSTRUCTIONS; void execute() { PORTD |= 0b01000000; _delay_loop_2(1024); PORTD &= 0b10111111; } int main() { DDRB = 0xFF; DDRD = 0xFF; PORTB = FUNCTION_SET; execute(); PORTB = DISPLAY_CONTROL; execute(); PORTB = DISPLAY_CLEAR; execute(); PORTB = ENTRY_MODE_SET; execute(); char* c = "Max "; while(1) { int i; for(i=0; c[i]!='\0'; i++) { PORTB = c[i]; execute(); } _delay_loop_2(32768); } return 0; }