// X25043/45 應用
 write_status(status)                    // 寫狀態，一般寫0
clr_wchdog(void)                         //清看門狗
unsigned char	read_byte(address)       //讀一個字節
void write_byte(address,Data)            //寫一個字節

#define	ALONE_COMPILE
#ifdef	ALONE_COMPILE
#include "INTRINS.H"
#endif

#ifndef nop2()
#define nop2()  _nop_();_nop_();_nop_()
#endif

#define WREN    0x06
#define WRDI    0x04
#define RDSR    0x05
#define WRSR    0x01
#define READ    0x03
#define WRITE   0x02

//#define	PORT	P1
sfr	PORT=0x90;              //25045的4根io腳接在同一端口，本例為p1
			                //請根據實際電路更改引腳定義
#define	_SI	0x80            //si接在p1.3，0x80=00001000b
#define	_SCK	0x40        //sck接在p1.2，0x80=00000100b
#define	_SO	0x20            //so接在p1.1   
#define	_CS	0x10            //cs接在p1.0

#ifndef	dword
	#define	dword	unsigned long
	#define	word	unsigned int
	#define	byte	unsigned char
	typedef	union
{
		word	w;
		byte	bh;
		byte	bl;
	}
WordType;

	typedef	union
{
		dword	dw;
		word	w[2];
		byte	b[4];
	}
DwordType;
#endif

void	_w_byte(Data)
	char Data;
{
	char i;
		
	PORT &= (_SCK^0xff);
	for(i=0;i<<255 ? (0x08|READ): READ));
	_w_byte((char)(address & 0x00ff));
	result=_r_byte();
	nop2();nop2();/////////////
	PORT |=_CS;
					               // Chip unselect 	
	return(result);
}

void	write_byte(address,Data)
	unsigned int address;
	char Data;
{
	write_status(WREN);
	nop2();nop2();/////////////
	PORT &= (_CS^0xff);
	nop2();nop2();/////////////
	_w_byte((unsigned char)(address>255 ? (0x08|WRITE): WRITE));
	_w_byte((unsigned char)(address & 0x00ff));
	_w_byte(Data);
	nop2();nop2();/////////////
	PORT |=_CS;
	wait_free();
	return;
}

unsigned long	read_data(format,address)
	unsigned char	format;
	unsigned int	address;
{	
	DwordType	result;

	switch(format&0xdf)
	{
	case'L':
		result.b[0]=read_byte(address);
		result.b[1]=read_byte(address+1);
		result.b[2]=read_byte(address+2);
		result.b[3]=read_byte(address+3);
		break;
	case'D':
		result.b[2]=read_byte(address);
		result.b[3]=read_byte(address+1);
		break;
	case'C':
		result.b[3]=read_byte(address);
		break;
	}
	return(result.dw);
}

void write_data(format,address,Data)
	unsigned char format;
	unsigned int address;
	DwordType data* Data;
{
	switch(format&0xdf)
	{
	case'L':
		write_byte(address  , Data->b[0]);
		write_byte(address+1, Data->b[1]);
		write_byte(address+2, Data->b[2]);
		write_byte(address+3, Data->b[3]);
		break;
	case'D':
		write_byte(address  , Data->b[2]);
		write_byte(address+1, Data->b[3]);
		break;
	case'C':
		write_byte(address  , Data->b[3]);
		break;
	}

}