#define F_CPU 4000000UL

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


typedef unsigned char byte;

// Hardware pin definitions
#define A0_PORT  PORTB
#define A0_DDR   DDRB
#define A0_BIT   1
#define RES_PORT PORTB
#define RES_DDR  DDRB
#define RES_BIT  0



void disp_send_lines();

void spi_init() {
	SPCR = (0<<SPIE)|(1<<SPE)|(0<<DORD)|(1<<MSTR)|(0<<CPOL)|(0<<CPHA)|(1<<SPR1)|(1<<SPR0);
	SPSR = (0<<SPI2X);
	_delay_ms(100);
}

void spi_master_send_char(byte Dat) {
	SPDR = Dat;
	while (!(SPSR & (1<<SPIF)));
}

void dogm_send(unsigned char spi_data, unsigned char a0)
{
	//a0 = 0: Command
	//a0 = 1: Display data

	//set / clear A0-Bit
	if (a0)
		A0_PORT |= (1<<A0_BIT);
	else
		A0_PORT &= ~(1<<A0_BIT);

	//Byte senden
	spi_master_send_char(spi_data);
}
#define dogm_send_command(command)      dogm_send(command, 0)
#define dogm_send_display_data(data)    dogm_send(data, 1)



void dogm_reset()
{
	//Reset display (50ms)
	RES_PORT &= ~(1<<RES_BIT); // RES\ = LOW (Reset)
	_delay_ms(100);
	RES_PORT |= (1<<RES_BIT); // RES\ = HIGH (kein Reset)
}


void disp_init()
{
	//uart_comment("[DOGM128] Initializing...");

	//SET DATA DIRECTION REGISTER
	//Outputs: (DDR=1)
	A0_DDR |= (1<<A0_BIT); //Output: A0
	RES_DDR |= (1<<RES_BIT); //Output: RES
	//Inputs: (DDR=0)
	//(none)


	//RESET
	dogm_reset(); //(100ms)


	//Display start line
	dogm_send_command(0x40); // Display start line 0

	//Bottom view
	dogm_send_command(0xA1); // ADC reverse
	dogm_send_command(0xC0); // Normal COM0~COM63

	//Normal / Inverted
	dogm_send_command(0xA6); // Display normal

	//Hardware options
	dogm_send_command(0xA2); // Set bias 1/9 (Duty 1/65)
	dogm_send_command(0x2F); // Booster, Regulator and Follower on
	dogm_send_command(0xF8); // Set internal Booster to 4x
	dogm_send_command(0x00);

	//Contrast options
	dogm_send_command(0x27); // Contrast set
	dogm_send_command(0x81);
	dogm_send_command(0x16);

	//Indicator options
	dogm_send_command(0xAC); // No indicator
	dogm_send_command(0x00);

	//(Init done)
	dogm_send_command(0xAF); // Display on
}



void disp_send_lines()
{
	uint8_t page;
	for (page = 0; page < 8; page++)
	{
		dogm_send_command(0xB0 + page); //Set page address to <page>
		dogm_send_command(0x10 + 0); //Set column address to 0 (4 MSBs)
		dogm_send_command(0x00 + 0); //Set column address to 0 (4 LSBs)
	
		uint8_t column;
		for (column = 0; column < 128; column++)
			dogm_send_display_data(0xAA);
	}
}

int main() {

	spi_init();

	disp_init();

	disp_send_lines();

	while (1);
}