#include <avr\io.h>

#define DD_MOSI PINB3

#define DD_SCK PINB5

#define DDR_SPI PORTB

void SPI_MasterInit(void)


{

// Set MOSI and SCK output, all others input

DDR_SPI = (1<<DD_MOSI)|(1<<DD_SCK);

// Enable SPI, Master,  set clock rate fck/16

SPCR = (1<<SPE)|(1<<MSTR)|(1<<SPR0);

}

void SPI_MasterTransmit(char cData)

{

/* Start transmission */

SPDR = cData;

/* Wait for transmission complete */

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

}

int main(void) {

SPI_MasterInit();

SPI_MasterTransmit('A');

   while(1) { }

return 0;
}