#ifdef ATMEGA32
#include <Mega32.h>
#elif defined(AT90S8515)
#include <90S8515.h>
#define SS 4
#define MOSI 5
#define SCK 7
#elif defined(ATMEGA8)
#include <Mega8.h>
#define SS 2
#define MOSI 3
#define SCK 5
#elif defined(ATMEGA48)
#include <Mega48.h>
#define SS 2
#define MOSI 3
#define SCK 5
#endif

#include <delay.h>
#include "led_driver.h"

void led_init(void)
{
    //CPOL=0,CPHA=0 -> Sample on rising edge, standard phase.
    #ifdef ATMEGA32
    SPCR=0b01010001;//Enable SPI, MSB first, master mode, 16 MHz/16 = 1 MHz clock.
    #elif defined(AT90S8515)||defined(ATMEGA8)||defined(ATMEGA48)
    SPCR=0b01010000;//Enable SPI, MSB first, master mode, 4 MHz/4 = 1 MHz clock.
    #endif
    
    //FIXME Flicker disappears when these lines are removed!
    DDRB.SS=1;//SS (LE).
    DDRB.MOSI=1;//MOSI.
    DDRB.SCK=1;//SCK.
    PORTB.SS=1;//Data latched on LE low (keep high).
}

void led_set(unsigned int on)
{
    unsigned char temp;

    PORTB.SS=1;//Data register transparent.

    SPDR=(on>>8)&0xFF;//MSB
    while(!(SPSR&0x80));//Wait for transfer complete.
    temp=SPDR;
    
    SPDR=on&0xFF;//LSB
    while(!(SPSR&0x80));//Wait for transfer complete.
    temp=SPDR;//Access SPDR to clear second SPIF flag.

    PORTB.SS=0;//Latch register.
}