/*
 * SPI interface whith the ST M95160 EEPROM
 */


#include	"pic1687x.h"
static bit CHIP_SELECT	@ ((unsigned)&PORTB*8+5);	// CHIP SELECT
int
spi_read(long int addres)
{
	int data;
	SSPBUF = 0x03;
	CHIP_SELECT = 0;
	do{}
	while(!STAT_BF);
	SSPBUF = 0x0;
	do{}
	while(!STAT_BF);
	SSPBUF = addres;
	do{}
	while(!STAT_BF);
	CKP = 0;
	SSPBUF = 0;
	do{}
	while(!STAT_BF);
	data = SSPBUF;
	CKP = 1;
	CHIP_SELECT = 1;
	return(data);
}


void
spi_write(unsigned char addres, unsigned char data)
{
	/* instruction */
	SSPBUF = 0x02;
	CHIP_SELECT = 0;
	do{}
	while(!STAT_BF);

	/* 16 bit addres */
	SSPBUF = 0x00;
	do{}
	while(!STAT_BF);

	SSPBUF = addres;
	do{}
	while(!STAT_BF);

	/* 8 bit data */
	SSPBUF = data;
	do{}
	while(!STAT_BF);
	CHIP_SELECT = 1;
}


void
spi_RDSR(unsigned unsigned char data)
{
	SSPBUF = 0x05;
	CHIP_SELECT = 0;
	do{}
	while(!STAT_BF);
	CKP = 0;
	SSPBUF = 0;
	do{}
	while(!STAT_BF);
	data = SSPBUF;
	CKP = 1;
	CHIP_SELECT = 1;

}


void
spi_WREN()
{
	SSPBUF = 0x06;
	CHIP_SELECT = 0;
	do{}
	while(!STAT_BF);
	CHIP_SELECT = 1;
};


void
spi_WRDI()
{
	SSPBUF = 0x04;
	CHIP_SELECT = 0;
	do{}
	while(!STAT_BF);
	CHIP_SELECT = 1;
};



void InitSPI(void)
{
	// SSPSTAT
	STAT_SMP 	= 0;	// INPUT DATA SAMPLED AT MIDDLE OF DATA
	STAT_CKE 	= 0;	// DATA TRANSMITTED ON RISING EDGE
	STAT_BF 	= 0;	// BF READY?
	// SSPCON
	SSPEN 		= 1;
	CKP 		= 1;
};