#include "spi.h"
#include <util/delay.h>


void spi_begin() {
#if defined(SPCR)
#error to write ...
	// Set SS to high so a connected chip will be "deselected" by default
	digitalWrite(SS, HIGH);
	// When the SS pin is set as OUTPUT, it can be used as
	// a general purpose output port (it doesn't influence
	// SPI operations).
	pinMode(SS, OUTPUT);
	// Warning: if the SS pin ever becomes a LOW INPUT then SPI
	// automatically switches to Slave, so the data direction of
	// the SS pin MUST be kept as OUTPUT.
	SPCR |= _BV(MSTR);
	SPCR |= _BV(SPE);
	// Set direction register for SCK and MOSI pin.
	// MISO pin automatically overrides to INPUT.
	// By doing this AFTER enabling SPI, we avoid accidentally
	// clocking in a single bit since the lines go directly
	// from "input" to SPI control.
	// http://code.google.com/p/arduino/issues/detail?id=888
	pinMode(SCK, OUTPUT);
	pinMode(MOSI, OUTPUT);
#else
    PRR &= ~(_BV(PRUSI));
	USICR = _BV(USIWM0);
	USCK_DDR |= _BV(USCK_BIT); //set the USCK pin as output
	DO_DDR |= _BV(DO_BIT); //set the DO pin as output
	DI_DDR &= ~_BV(DI_BIT); //set the DI pin as input
#endif
}

uint8_t spi_transfer(uint8_t b) {
#if defined(SPCR)
	SPDR = b;
	while (!(SPSR & _BV(SPIF)));
	return SPDR;
#else
	USIDR = b;
	USISR = _BV(USIOIF);
	do {
		USICR = _BV(USIWM0) | _BV(USICS1) | _BV(USICLK) | _BV(USITC);
//		_delay_ms(1);
	}while ((USISR & _BV(USIOIF)) == 0);
	return USIDR;
#endif
}

void spi_end() {
#if defined(SPCR)
	SPCR &= ~_BV(SPE);
#else
	USICR &= ~(_BV(USIWM1) | _BV(USIWM0));
#endif
}

void spi_setBitOrder(uint8_t bitOrder)
{
#if defined(SPCR)
	if(bitOrder == LSBFIRST) {
		SPCR |= _BV(DORD);
	} else {
		SPCR &= ~(_BV(DORD));
	}
#endif
}

void spi_setDataMode(uint8_t mode)
{
#if defined(SPCR)
	SPCR = (SPCR & ~SPI_MODE_MASK) | mode;
#else

#endif
}