#define F_CPU 1000000
#include <avr/io.h>
#include <avr/interrupt.h>
#include <avr/pgmspace.h>
#include <util/delay.h>

#define LCD_SCE_HI			PORTA |= (1<<1)
#define LCD_SCE_LO			PORTA &= ~(1<<1)
#define LCD_RST_HI			PORTA |= (1<<0)
#define LCD_RST_LO			PORTA &= ~(1<<0)
#define LCD_DC_HI			PORTD |= (1<<2)
#define LCD_DC_LO			PORTD &= ~(1<<2)
#define LCD_DN_HI			PORTD |= (1<<3)
#define LCD_DN_LO			PORTD &= ~(1<<3)
#define LCD_SCLK_HI			PORTD |= (1<<4)
#define LCD_SCLK_LO			PORTD &= ~(1<<4)
#define LCD_BACKLIGHT_HI	PORTD |= (1<<5)
#define LCD_BACKLIGHT_LO	PORTD &= ~(1<<5)

#define LCD_C 0
#define LCD_D 1

#define LCD_WIDTH	84
#define LCD_HEIGHT	48

const uint8_t PROGMEM ascii_table[] =
{
	0x00, 0x00, 0x00, 0x00, 0x00, // 20
	0x00, 0x00, 0x5f, 0x00, 0x00, // 21 !
	0x00, 0x07, 0x00, 0x07, 0x00, // 22 "
	0x14, 0x7f, 0x14, 0x7f, 0x14, // 23 #
	0x24, 0x2a, 0x7f, 0x2a, 0x12, // 24 $
	0x23, 0x13, 0x08, 0x64, 0x62, // 25 %
	0x36, 0x49, 0x55, 0x22, 0x50, // 26 &
	0x00, 0x05, 0x03, 0x00, 0x00, // 27 '
	0x00, 0x1c, 0x22, 0x41, 0x00, // 28 (
	0x00, 0x41, 0x22, 0x1c, 0x00, // 29 )
	0x14, 0x08, 0x3e, 0x08, 0x14, // 2a *
	0x08, 0x08, 0x3e, 0x08, 0x08, // 2b +
	0x00, 0x50, 0x30, 0x00, 0x00, // 2c ,
	0x08, 0x08, 0x08, 0x08, 0x08, // 2d -
	0x00, 0x60, 0x60, 0x00, 0x00, // 2e .
	0x20, 0x10, 0x08, 0x04, 0x02, // 2f /
	0x3e, 0x51, 0x49, 0x45, 0x3e, // 30 0
	0x00, 0x42, 0x7f, 0x40, 0x00, // 31 1
	0x42, 0x61, 0x51, 0x49, 0x46, // 32 2
	0x21, 0x41, 0x45, 0x4b, 0x31, // 33 3
	0x18, 0x14, 0x12, 0x7f, 0x10, // 34 4
	0x27, 0x45, 0x45, 0x45, 0x39, // 35 5
	0x3c, 0x4a, 0x49, 0x49, 0x30, // 36 6
	0x01, 0x71, 0x09, 0x05, 0x03, // 37 7
	0x36, 0x49, 0x49, 0x49, 0x36, // 38 8
	0x06, 0x49, 0x49, 0x29, 0x1e, // 39 9
	0x00, 0x36, 0x36, 0x00, 0x00, // 3a :
	0x00, 0x56, 0x36, 0x00, 0x00, // 3b ;
	0x08, 0x14, 0x22, 0x41, 0x00, // 3c <
	0x14, 0x14, 0x14, 0x14, 0x14, // 3d =
	0x00, 0x41, 0x22, 0x14, 0x08, // 3e >
	0x02, 0x01, 0x51, 0x09, 0x06, // 3f ?
	0x32, 0x49, 0x79, 0x41, 0x3e, // 40 @
	0x7e, 0x11, 0x11, 0x11, 0x7e, // 41 A
	0x7f, 0x49, 0x49, 0x49, 0x36, // 42 B
	0x3e, 0x41, 0x41, 0x41, 0x22, // 43 C
	0x7f, 0x41, 0x41, 0x22, 0x1c, // 44 D
	0x7f, 0x49, 0x49, 0x49, 0x41, // 45 E
	0x7f, 0x09, 0x09, 0x09, 0x01, // 46 F
	0x3e, 0x41, 0x49, 0x49, 0x7a, // 47 G
	0x7f, 0x08, 0x08, 0x08, 0x7f, // 48 H
	0x00, 0x41, 0x7f, 0x41, 0x00, // 49 I
	0x20, 0x40, 0x41, 0x3f, 0x01, // 4a J
	0x7f, 0x08, 0x14, 0x22, 0x41, // 4b K
	0x7f, 0x40, 0x40, 0x40, 0x40, // 4c L
	0x7f, 0x02, 0x0c, 0x02, 0x7f, // 4d M
	0x7f, 0x04, 0x08, 0x10, 0x7f, // 4e N
	0x3e, 0x41, 0x41, 0x41, 0x3e, // 4f O
	0x7f, 0x09, 0x09, 0x09, 0x06, // 50 P
	0x3e, 0x41, 0x51, 0x21, 0x5e, // 51 Q
	0x7f, 0x09, 0x19, 0x29, 0x46, // 52 R
	0x46, 0x49, 0x49, 0x49, 0x31, // 53 S
	0x01, 0x01, 0x7f, 0x01, 0x01, // 54 T
	0x3f, 0x40, 0x40, 0x40, 0x3f, // 55 U
	0x1f, 0x20, 0x40, 0x20, 0x1f, // 56 V
	0x3f, 0x40, 0x38, 0x40, 0x3f, // 57 W
	0x63, 0x14, 0x08, 0x14, 0x63, // 58 X
	0x07, 0x08, 0x70, 0x08, 0x07, // 59 Y
	0x61, 0x51, 0x49, 0x45, 0x43, // 5a Z
	0x00, 0x7f, 0x41, 0x41, 0x00, // 5b [
	0x02, 0x04, 0x08, 0x10, 0x20, // 5c ¥
	0x00, 0x41, 0x41, 0x7f, 0x00, // 5d ]
	0x04, 0x02, 0x01, 0x02, 0x04, // 5e ^
	0x40, 0x40, 0x40, 0x40, 0x40, // 5f _
	0x00, 0x01, 0x02, 0x04, 0x00, // 60 `
	0x20, 0x54, 0x54, 0x54, 0x78, // 61 a
	0x7f, 0x48, 0x44, 0x44, 0x38, // 62 b
	0x38, 0x44, 0x44, 0x44, 0x20, // 63 c
	0x38, 0x44, 0x44, 0x48, 0x7f, // 64 d
	0x38, 0x54, 0x54, 0x54, 0x18, // 65 e
	0x08, 0x7e, 0x09, 0x01, 0x02, // 66 f
	0x0c, 0x52, 0x52, 0x52, 0x3e, // 67 g
	0x7f, 0x08, 0x04, 0x04, 0x78, // 68 h
	0x00, 0x44, 0x7d, 0x40, 0x00, // 69 i
	0x20, 0x40, 0x44, 0x3d, 0x00, // 6a j
	0x7f, 0x10, 0x28, 0x44, 0x00, // 6b k
	0x00, 0x41, 0x7f, 0x40, 0x00, // 6c l
	0x7c, 0x04, 0x18, 0x04, 0x78, // 6d m
	0x7c, 0x08, 0x04, 0x04, 0x78, // 6e n
	0x38, 0x44, 0x44, 0x44, 0x38, // 6f o
	0x7c, 0x14, 0x14, 0x14, 0x08, // 70 p
	0x08, 0x14, 0x14, 0x18, 0x7c, // 71 q
	0x7c, 0x08, 0x04, 0x04, 0x08, // 72 r
	0x48, 0x54, 0x54, 0x54, 0x20, // 73 s
	0x04, 0x3f, 0x44, 0x40, 0x20, // 74 t
	0x3c, 0x40, 0x40, 0x20, 0x7c, // 75 u
	0x1c, 0x20, 0x40, 0x20, 0x1c, // 76 v
	0x3c, 0x40, 0x30, 0x40, 0x3c, // 77 w
	0x44, 0x28, 0x10, 0x28, 0x44, // 78 x
	0x0c, 0x50, 0x50, 0x50, 0x3c, // 79 y
	0x44, 0x64, 0x54, 0x4c, 0x44, // 7a z
	0x00, 0x08, 0x36, 0x41, 0x00, // 7b {
	0x00, 0x00, 0x7f, 0x00, 0x00, // 7c |
	0x00, 0x41, 0x36, 0x08, 0x00, // 7d }
};

void lcd_write(uint8_t dc, uint8_t data)
{
	if (dc)
		LCD_DC_HI;
	else
		LCD_DC_LO;
	LCD_SCE_LO;
	for (int i = 0; i < 8; i++)
	{
		if (data&(1<<7))
			LCD_DN_HI;
		else
			LCD_DN_LO;
		LCD_SCLK_LO;
		LCD_SCLK_HI;
		data <<= 1;
	}
	LCD_SCE_HI;
	LCD_DN_LO;
}

void lcd_char(char c)
{
	lcd_write(LCD_D, 0x00);
	for (int i = 0; i < 5; i++)
		lcd_write(LCD_D, pgm_read_byte(ascii_table+(c-0x20)*5+i));
	lcd_write(LCD_D, 0x00);
}

void lcd_str(const char* str)
{
	while (pgm_read_byte(str))
	{
		lcd_char(pgm_read_byte(str));
		str++;
	}
}

void lcd_clear(void)
{
	for (int i = 0; i < LCD_WIDTH*LCD_HEIGHT/8; i++)
		lcd_write(LCD_D, 0x00);
}

void lcd_backlight(uint8_t enabled)
{
	if (enabled)
		LCD_BACKLIGHT_HI;
	else
		LCD_BACKLIGHT_LO;
}

void lcd_init(void)
{
	// configure the LCD pins as outputs
	DDRA |= (1<<1);
	DDRA |= (1<<0);
	DDRD |= (1<<2);
	DDRD |= (1<<3);
	DDRD |= (1<<4);
	DDRD |= (1<<5);
	// initialize the LCD pins
	LCD_SCE_HI;
	LCD_BACKLIGHT_HI;
	LCD_RST_LO;
	LCD_RST_HI;
	// extended instruction set
	lcd_write(LCD_C, 0x21);
	// set Vop to 5V
	lcd_write(LCD_C, 0xA0);
	// set the temperature coefficient
	lcd_write(LCD_C, 0x04);
	// set the bias system
	lcd_write(LCD_C, 0x15);
	// active mode, horizontal addressing, basic instruction set
	lcd_write(LCD_C, 0x20);
	// normal mode
	lcd_write(LCD_C, 0x0C);
	// clear the LCD
	lcd_clear();
}

int main(void)
{
	lcd_init();
	int j = 0;
	while (1)
	{
		lcd_clear();
		for (int i = 0; i < 6; i++)
		{
			if ((i+j)%2 == 0)
				lcd_str(PSTR("Hello, World"));
			else
				lcd_str(PSTR("------------"));
		}
		j++;
		_delay_ms(1000);
	}
	return 0;
}