heptagon-arduino/lcd_hept/arduinolib.c

#include <avr/io.h>
#include <util/delay.h>
#include "arduinolib.h"

/* Configure the pins of arduino */
void Arduinolib__dinit_step(Arduinolib__dinit_out *out){
    //control
    LCD_E_DDR |= (1 << LCD_E_PIN);
    LCD_RS_DDR |= (1 << LCD_RS_PIN);
    //data 
    LCD_D4_DDR |= (1 << LCD_D4_PIN);
    LCD_D5_DDR |= (1 << LCD_D5_PIN);
    LCD_D6_DDR |= (1 << LCD_D6_PIN);
    LCD_D7_DDR |= (1 << LCD_D7_PIN);
}

/* Initialize the LCD as described in the datasheet */
void Arduinolib__lcd_init_step(Arduinolib__lcd_init_out *out){

    _delay_ms(50); //power delay more than 15ms

    LCD_RS_PORT &= ~(1 << LCD_RS_PIN); //RS to low
    LCD_E_PORT &= ~(1 << LCD_E_PIN); //E to low


    // "reboot process"
    Arduinolib__lcd_write_out *o1;
    Arduinolib__lcd_write_step(LCD_FUNCTION_SET_8bit, o1);
    _delay_ms(10); //more than 4.1ms
    Arduinolib__lcd_write_out *o2;
    Arduinolib__lcd_write_step(LCD_FUNCTION_SET_8bit,o2);
    _delay_us(200); //more than 100us
    Arduinolib__lcd_write_out *o3;
    Arduinolib__lcd_write_step(LCD_FUNCTION_SET_8bit, o3);
    _delay_us(200); //more than 100us

    //set to 4bit
    Arduinolib__lcd_write_out *o4;
    Arduinolib__lcd_write_step(LCD_FUNCTION_SET_4bit, o4);
    _delay_us(80); //more than 39us
    Arduinolib__lcd_cmd_out *o5;
    Arduinolib__lcd_cmd_step(LCD_FUNCTION_SET_4bit, o5); 
    _delay_us(80); //more than 39us

    //send instructions
    Arduinolib__lcd_cmd_out *o6;
    Arduinolib__lcd_cmd_step(LCD_DISPLAY_OFF, o6);
    _delay_us(80); //more than 39us
    Arduinolib__lcd_cmd_out *o7;
    Arduinolib__lcd_cmd_step(LCD_CLEAR, o7);
    _delay_ms(3); //more than 1.53 ms
    Arduinolib__lcd_cmd_out *o8;
    Arduinolib__lcd_cmd_step(LCD_ENTRY_MODE, o8);
    _delay_us(80); //more than 39us
    Arduinolib__lcd_cmd_out *o9;
    Arduinolib__lcd_cmd_step(LCD_DISPLAY_ON, o9);
    _delay_us(80); //more than 39us


    // if we use this code the msg is printed ///
    /*uint8_t msg[] = "Arduino";
    Arduinolib__lcd_string_out *o;
    Arduinolib__lcd_string_step(msg, o);*/

}

/* send an 8bit information to the LCD register in order to be written */
void Arduinolib__lcd_write_step(uint8_t info, Arduinolib__lcd_write_out *out){
    //(info & 1 << 4) ? LCD_D4_PORT |= (1 << LCD_D4_PIN) :  LCD_D4_PORT &= ~(1 << LCD_D4_PIN)
    if (info & 1<<4){
        LCD_D4_PORT |= (1 << LCD_D4_PIN);
    }
    else {
        LCD_D4_PORT &= ~(1 << LCD_D4_PIN);
    }

    if (info & 1<<5){
        LCD_D5_PORT |= (1 << LCD_D5_PIN);
    }
    else {
        LCD_D5_PORT &= ~(1 << LCD_D5_PIN);
    }

    if (info & 1<<6){
        LCD_D6_PORT |= (1 << LCD_D6_PIN);
    }
    else {
        LCD_D6_PORT &= ~(1 << LCD_D6_PIN);
    }
    if (info & 1<<7){
        LCD_D7_PORT |= (1 << LCD_D7_PIN);
    }
    else {
        LCD_D7_PORT &= ~(1 << LCD_D7_PIN);
    }

    //pulse the Enable pin to indicate we have written the data
    LCD_E_PORT |= (1 << LCD_E_PIN); //high
    _delay_us(1);
    LCD_E_PORT &= ~(1 << LCD_E_PIN); //low
    _delay_us(1);
}

/* send an 8bit instruction to the LCD instruction register */
void Arduinolib__lcd_cmd_step(uint8_t cmd, Arduinolib__lcd_cmd_out *out){

    LCD_RS_PORT &= ~(1 << LCD_RS_PIN); //low
    LCD_E_PORT &= ~(1 << LCD_E_PIN); //low
    Arduinolib__lcd_write_out *o1;
    Arduinolib__lcd_write_step(cmd, o1); // upper 4 bits
    Arduinolib__lcd_write_out *o2;
    Arduinolib__lcd_write_step(cmd << 4, o2); // lower 4 bits
}

/* send an 8bit data character to the LCD register */
void Arduinolib__lcd_char_step(uint8_t char_data, Arduinolib__lcd_char_out *out){

    LCD_RS_PORT |= (1 << LCD_RS_PIN); //high
    LCD_E_PORT &= ~(1 << LCD_E_PIN); //low
    Arduinolib__lcd_write_out *o1;
    Arduinolib__lcd_write_step(char_data, o1); // upper 4 bits
    Arduinolib__lcd_write_out *o2;
    Arduinolib__lcd_write_step(char_data << 4, o2); // lower 4 bits
}

/* give a string to display to the LCD */
void Arduinolib__lcd_string_step(uint8_t lstring[], int line, Arduinolib__lcd_string_out *out){

    Arduinolib__lcd_cmd_out *o1;
    Arduinolib__lcd_cmd_out *o2;
    if (line == 1) { 
        Arduinolib__lcd_cmd_step(LCD_CURSOR_SET | LCD_START_LINE2, o1);
        _delay_us(80); //more than 
    } else {
        Arduinolib__lcd_cmd_step(LCD_CURSOR_SET | LCD_START_LINE1, o2);
        _delay_us(80);
    }
    volatile int i = 0;
    for (i = 0; lstring[i] != 0 ; i++) {
        Arduinolib__lcd_char_out *o3;
        Arduinolib__lcd_char_step(lstring[i], o3);
        _delay_us(80); //more than 39us
    }
}