/*------————————————————————
〖说明〗这是一款老的芯片驱动程序，它可兼容x25020的驱动C51编写的
—————————————————————*/
/* x25045的读写程序 用c51写的 */
#define CS P2.7 /*单片机p2.7为片选 可以改为你的实际引脚 */
#define SO P2.6 /*数据输出 */
#define SK P2.5 /* 时钟 */
#define SI P2.4 /* 数据输入*/

#define WREN 0x06
#define WRDI 0x04
#define RDSR 0x05
#define WRSR 0x01
#define READ0 0x03
#define READ1 0x0b
#define WRITE0 0x02
#define WRITE1 0x0a

unsigned char Read8()
{
bit bData;
unsigned char cLoop;
unsigned char cData;
for(cLoop=0;cLoop<8;cLoop++)
{
SK=1;
SK=0;
bData=SO;
cData<<=1;
if(bData)
{
cData|=0x01;
}
}
return cData;
}

void Write8(unsigned char cData)
{
unsigned char cLoop;
for(cLoop=0;cLoop<8;cLoop++)
{
if((cData&0x80)==0)
{
SI=0;
}
else
{
SI=1;
}
SK=0;
SK=1;
cData<<=1;
}
}

unsigned char ReadSR()
{
unsigned char cData;
CS=0;
Write8(RDSR);
cData=Read8();
CS=1;
return cData;
}

unsigned char WriteSR(unsigned char cData)
{
unsigned char cTemp;
cTemp=ReadSR();
if((cTemp&0x01)==1)
return 0;
CS=0;
Write8(WREN);
CS=1;
CS=0;
Write8(WRSR);
Write8(cData);
CS=1;
return 1;
}

void Write1B(unsigned char cData,unsigned char cAddress,bit bRegion)
/* 写入一个字节，cData为写入的数，cAddress为写入地址，bRegion为页 */
{
while((ReadSR()&0x01)==1)
{
}
CS=0;
Write8(WREN);
CS=1;
CS=0;
if(bRegion==0)
{
Write8(WRITE0);
}
else
{
Write8(WRITE1);
}
Write8(cAddress);
Write8(cData);
SK=0;
CS=1;
}

unsigned char Read1B(unsigned char cAddress,bit bRegion)
/* 读入一个字节，cAddress为读入地址，bRegion为页 */
{
unsigned char cData;
while((ReadSR()&0x01)==1)
{
}
CS=0;
if(bRegion==0)
{
Write8(READ0);
}
else
{
Write8(READ1);
}
Write8(cAddress);
cData=Read8();
CS=1;
return cData;
}