LCDModule.cpp

#include <util/delay.h>
#include <Arduino.h>

#include "LCDModule.h"

/// Custom characters definition -------------------------------------------------

#define SYMB_COUNT 2

uint8_t light_val = LCDEX_LIGHT;

const uint8_t symbols[] PROGMEM = {
  0b10000, 0b11000, 0b11100, 0b11110, 0b11100, 0b11000, 0b10000, 0b00000,//Play
  0b00000, 0b00111, 0b11001, 0b10001, 0b10001, 0b11111, 0b00000, 0b00000,//Folder
};


//// TWI(I2C) MODULE PART --------------------------------------------------------

unsigned char twi_start(unsigned char address)
{
    uint8_t tmp;
    TWCR = _BV(TWEN) | _BV(TWINT) | _BV(TWSTA);
    
    while(!(TWCR & _BV(TWINT)));
    
    tmp = TW_STATUS & 0xF8;
    if ( (tmp != TW_START) && (tmp != TW_REP_START)) return 1;

    // send address
    TWDR = address << 1; // add bit 0 for write
    TWCR = _BV(TWINT) | _BV(TWEN);

    while(!(TWCR & _BV(TWINT)));

    tmp = TW_STATUS & 0xF8;
    if ( (tmp != TW_MT_SLA_ACK) && (tmp != TW_MR_SLA_ACK) ) return 1;

    return 0;
}

void twi_stop(void)
{
    TWCR = _BV(TWINT) | _BV(TWEN) | _BV(TWSTO);  
    while(TWCR & _BV(TWSTO));
}

void twi_send_byte(unsigned char data)
{
    twi_start(LCDEX_ADDR);

    TWDR = data | _BV(LCDEX_LIGHT & light_val); //temporary
    TWCR = (1<<TWINT) | (1<<TWEN);

    while(!(TWCR & (1<<TWINT)));

    twi_stop();
}

//// -----------------------------------------------------------------------------

void strobe_en(uint8_t data)
{
    data |= _BV(LCDEX_EN);
    twi_send_byte(data);
    lcd_e_delay();
    data &= ~_BV(LCDEX_EN);
    twi_send_byte(data);
}

unsigned char data_remap(unsigned char data)
{
    unsigned char data_out = 0;
    if(data & 16) data_out |= _BV(LCDEX_D4);
    if(data & 32) data_out |= _BV(LCDEX_D5);
    if(data & 64) data_out |= _BV(LCDEX_D6);
    if(data & 128) data_out |= _BV(LCDEX_D7);
    return data_out;
}

void lcd_command(unsigned char cmd)
{
    uint8_t lcd_data = data_remap(cmd);
    lcd_data &= ~_BV(LCDEX_RS);
    strobe_en(lcd_data);
    twi_send_byte(lcd_data);
    _delay_us(37);
 
    lcd_data = data_remap(cmd<<4);
    lcd_data &= ~_BV(LCDEX_RS);
    strobe_en(lcd_data);
    twi_send_byte(lcd_data);
    if(cmd & 0b11111100) _delay_us(37); else _delay_ms(2);
}

void lcd_putch(unsigned char chr)
{
    uint8_t lcd_data = data_remap(chr);
    lcd_data |= _BV(LCDEX_RS);
    strobe_en(lcd_data);
    _delay_us(37);
 
    lcd_data = data_remap(chr<<4);
    lcd_data |= _BV(LCDEX_RS);
    strobe_en(lcd_data);
    twi_send_byte(lcd_data);
    _delay_ms(2);
}

void lcd_generate_char(uint8_t num, uint8_t data_num)
{
    lcd_command( LCD_SET_CGADR | (num << 3) );

    const char *p = (const char PROGMEM *)(symbols + data_num * 8);

    for ( uint8_t i=0; i < 8; i++ )
        lcd_putch( pgm_read_byte_near(p++) );
}

void LCD_init()
{

    TWI_PORT |= _BV(TWI_SCL) | _BV(TWI_SDA);  // Set Pull-Up on SCL, SDA
    TWI_DDR &=~(_BV(TWI_SCL) | _BV(TWI_SDA)); // Set SCL,SDA as input

    // set bitrate
    TWSR = 0;                         /* no prescaler */
    TWBR = ((F_CPU/SCL_CLOCK)-16)/2;  /* must be > 10 for stable operation */    

    uint8_t lcd_data = 0b00000000;
    twi_send_byte(lcd_data);
    _delay_ms(40);

    // 8bit mode
    lcd_data = data_remap(0b00110000);
    twi_send_byte(lcd_data);

    strobe_en(lcd_data);  
    _delay_ms(5);              //delay > 4,1ms
    strobe_en(lcd_data);
    _delay_us(100);
    strobe_en(lcd_data);
    _delay_us(100);

    // set 4bit mode
    lcd_data = data_remap(0b00100000);
    twi_send_byte(lcd_data);
    strobe_en(lcd_data);
    twi_send_byte(lcd_data);
    _delay_us(100);
    
    // 4-bit-Mode already enabled
    lcd_command(LCD_SET_FUNCTION | LCD_FUNCTION_4BIT | LCD_FUNCTION_2LINE | LCD_FUNCTION_5X7);
    lcd_command(LCD_SET_DISPLAY | LCD_DISPLAY_ON | LCD_CURSOR_OFF | LCD_BLINKING_OFF);
    lcd_command(LCD_SET_ENTRY | LCD_ENTRY_INCREASE | LCD_ENTRY_NOSHIFT);
    LCD_clear();

    for(uint8_t i=0; i < SYMB_COUNT; i++) lcd_generate_char(i,i);
}

////////////////////////////////////////////////////////////////////////////////

/// clear LCD
void LCD_clear()
{
    lcd_command( LCD_CLEAR_DISPLAY );
}

////////////////////////////////////////////////////////////////////////////////

/// move cursor to HOME position
void LCD_home()
{
    lcd_command( LCD_CURSOR_HOME );
}

////////////////////////////////////////////////////////////////////////////////

void LCD_light_on()
{
    light_val = LCDEX_LIGHT;
    twi_send_byte(0);
}

////////////////////////////////////////////////////////////////////////////////

void LCD_light_off()
{
    light_val = 0;
    twi_send_byte(0);
}

uint8_t LCD_check_light()
{
    return light_val;
}
////////////////////////////////////////////////////////////////////////////////

/// set cursor position
void LCD_setcursor(uint8_t x, uint8_t y)
{
   switch(y)
   {
        case 0: lcd_command(LCD_SET_DDADR + LCD_DDADR_LINE1 + x); break;
        case 1: lcd_command(LCD_SET_DDADR + LCD_DDADR_LINE2 + x); break;
        case 2: lcd_command(LCD_SET_DDADR + LCD_DDADR_LINE3 + x); break;
        case 3: lcd_command(LCD_SET_DDADR + LCD_DDADR_LINE4 + x); break;
   }
}

/// print string
void LCD_print(const char* txt)
{
    for(uint8_t i = 0; i < strlen(txt); i++) lcd_putch(txt[i]);
}

/// print string at position x,y
void LCD_print(uint8_t x, uint8_t y, const char* txt)
{
    LCD_setcursor(x,y);
    LCD_print(txt);
}

////////////////////////////////////////////////////////////////////////////////

/// print string from programm memory (from flash)
void LCD_print(const __FlashStringHelper *txt)
{
    const char *p = (const char PROGMEM *)txt;
    for(;;) {
      char c = pgm_read_byte_near(p++);
      if(c == 0) break;
      lcd_putch(c);
    }
}

/// print string form program memory at position x,y
void LCD_print(uint8_t x, uint8_t y, const __FlashStringHelper *txt)
{
    LCD_setcursor(x,y);
    LCD_print(txt);
}

////////////////////////////////////////////////////////////////////////////////

/// print single digit
void LCD_print(uint8_t num)
{
    lcd_putch(num + 0x30);
}

/// print single digit at position x,y
void LCD_print(uint8_t x, uint8_t y, uint8_t num)
{
    LCD_setcursor(x,y);
    lcd_putch(num + 0x30);
}

////////////////////////////////////////////////////////////////////////////////

/// print single char
void LCD_print_char(uint8_t char_num)
{
    lcd_putch(char_num);
}

/// print single char at position x,y
void LCD_print_char(uint8_t x, uint8_t y, uint8_t char_num)
{
    LCD_setcursor(x,y);
    lcd_putch(char_num);
}