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


#define SPI_DDR DDRB
#define SPI_MOSI DDB3
#define SPI_MISO DDB4
#define SPI_SCK DDB5
#define LCD_CS DDB2
#define LCD_RESET DDB1

#define LCD_CS_1 PORTB |= (1 << LCD_CS);
#define LCD_CS_0 PORTB &= ~(1 << LCD_CS);
#define LCD_RESET_1 PORTB |= (1 << LCD_RESET);
#define LCD_RESET_0 PORTB &= ~(1 << LCD_RESET);

void lcd_init(void) {
	LCD_CS_1;
	_delay_ms(1);
	LCD_CS_0;
	spi_masterInit();
	LCD_CS_1;

	
	//Reset - Achtung: Reset-Leitung wird durch Schaltung invertiert
	LCD_CS_0;
	_delay_ms(1);
	LCD_RESET_0
	_delay_ms(1);
	//_delay_us(200);
	LCD_RESET_1
	_delay_ms(1);
	LCD_RESET_0
	_delay_ms(1);
	LCD_CS_1;
	_delay_ms(1);


	spi_sendCommand(0x3A);     //8 bit data length extension Bit RE=1; REV=0

	//_delay_ms(100);

	spi_sendCommand(0x09);     //4 line display

	//_delay_ms(50);

	spi_sendCommand(0x06);    //bottom view
	//_delay_ms(50);

	spi_sendCommand(0x1E);	//BS1=1
	//_delay_ms(50);

	spi_sendCommand(0x39);	//8 bit data length extension Bit RE=0; IS=1
	//_delay_ms(50);

	spi_sendCommand(0x1B);	//BS0=1 -> Bias=1/6
	//_delay_ms(50);

	spi_sendCommand(0x6E);	//Devider on and set value
	//_delay_ms(50);

	spi_sendCommand(0x56);	//Booster on and set contrast (DB1=C5, DB0=C4)
	//_delay_ms(50);

	spi_sendCommand(0x7A);	//Set contrast (DB3-DB0=C3-C0)
	//spi_masterTransmit(0x74);	//Set contrast (DB3-DB0=C3-C0)
	//_delay_ms(50);

	spi_sendCommand(0x38);	//8 bit data length extension Bit RE=0; IS=0
	//_delay_ms(50);

	spi_sendCommand(0x0F);	//Display on, cursor on, blink on
	//_delay_ms(50);

	_delay_ms(20);    // wait

	spi_sendCommand(0x02);	//Home

	spi_sendCommand(0x80);	//
	spi_sendData(0x30);	//0 anzeigen

}




void spi_masterInit(void) {
	//Output PINS
	SPI_DDR |= 
		(1<<LCD_CS) | 
		(1<<SPI_MOSI) | 
		(1<<SPI_SCK) | 
		(1 << LCD_RESET);

	SPCR = (1<<SPE)			//SPI enable
			| (1<<MSTR)		//SPI as master
			| (1<<SPR0)		// 1/16 Systemtakt -> 2MHz/16 ~ 125kHz
			| (1<<DORD)		//LSB first
			| (1<<CPOL)	//SPI Mode 3 (1)
			| (1<<CPHA)	//SPI Mode 3 (1)
			;	

	//Clear interrupt
	uint8_t x = SPSR;
	x = SPDR;
}

void spi_put(uint8_t data) {
	SPDR = data;
	while(!(SPSR & (1<<SPIF)));
	delay_ms(1);
}

void spi_sendData(uint8_t data) {
	LCD_CS_0;
	
	spi_put(0x5F);
	spi_put(data & 0x0F);
	spi_put((data >> 4) & 0x0F);

	LCD_CS_1;
}

void spi_sendCommand(uint8_t data) {
	LCD_CS_0;
	
	spi_put(0x1F);
	spi_put(data & 0x0F); 
	spi_put((data >> 4) & 0x0F);

	LCD_CS_1;
}

void spi_slaveInit(void) {

	SPI_DDR |= (1<<SPI_MISO);

	SPCR = (1<<SPE);

}

uint8_t spi_slaveReceive(void) {

	while(!(SPSR & (1<<SPIF)));

	return SPDR;

}