/*
 * DAC.c
 *
 * Created: 15.02.2017 17:59:51
 *  Author: Шамиль
 */

#define F_CPU 8000000
#include <avr/io.h>
#include <util/delay.h>

#define SPI_DDR DDRB
#define SPI_PORT PORTB
#define MOSI 3
#define CLK 5
#define CS 2

/*
- управляющий регистр SPCR,
- статусный регистр SPSR,
- регистр данных SPDR.
*/

void spi_init(){
    SPI_DDR |= ( 1 << MOSI )|( 1 << CLK )|( 1 << CS );
    SPI_PORT = ( 1 << CS );
    SPI_DDR |= ( 1 << MOSI )|( 1 << CLK )|( 1 << CS );
    SPCR = ( 1 << SPE )|( 1 << MSTR );
    SPSR = ( 1 << SPI2X );
}

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

void convert_DAC (float Voltage){
      unsigned int Level = (unsigned int)(Voltage * 4096) / 5;
      unsigned int M_Level = Level >> 8;
      M_Level |= 0x70;
      SPI_PORT &=~ ( 1 << CS );
      SPDR = M_Level;
      while(!(SPSR & (1<<SPIF)));

      SPDR = Level;
      while(!(SPSR & (1<<SPIF)));
      SPI_PORT |= ( 1 << CS );
}

int main(void){
    spi_init();
    while(1){
    for ( float i = 0; i < 5; i = i+0.1){
    convert_DAC(i);
    }
    convert_DAC(0);
    }
}