x5045.c

x5045是一个带串行E2PROM的CPU监控芯片

X5045.H

#ifndef X5045_h
#define X5045_h


#define WDT1_4  0x00;
#define WDT600  0x10;
#define WDT200  0x20;
#define WDTDIS  0x30;

//BIT
sbit B_CS5045=P2^0;
sbit B_SO5045=P2^1;
sbit B_SCLK5045=P2^3;
sbit B_SI5045=P2^2;

extern unsigned char data tcX5045;

void RstWDT(void);
void WrB5045(unsigned char,unsigned char) reentrant;      //写入单字节数据
unsigned char RdB5045(unsigned char);           //读出单字节数据
void byteout(unsigned char);                    //向5045输出单字节
void wip_chk(void);                             //等待5045结束内部写周期
unsigned char rdsr(void);                       //5045状态寄存器读出程序
unsigned char bytein(void);                     //从5045读出一字节数据
unsigned char readx(void);                      //读地址,地址位于100h
void wrsr(unsigned char);                       //5045状态寄存器写入程序
void wren(void);                                //写允许
void wrdi(void);                                //写禁止

#endif


/*
X5045/3 读写驱动
*/

#include <reg51.h>
#include "X5045.h"

//复位看门狗
void RstWDT()
{
    B_CS5045=0;
    B_CS5045=1;
}

//向X5045写入单字节数据
//输入：x,待写数据,address,写入数据的地址
void WrB5045(unsigned char x,unsigned char address) reentrant //数据,地址
{
        wren();
        B_SCLK5045=0;
        B_CS5045=0;
        byteout(0x2); //write
        byteout(address);
        byteout(x);
        B_SCLK5045=0;
        B_CS5045=1;
        wip_chk();
        wrdi();
}

//从X5045读入单字节数据
//输入：address,待读数据地址
//返回：读出的数据
unsigned char RdB5045(unsigned char address)
{
        unsigned char data x;
        B_SCLK5045=0;
        B_CS5045=0;
        byteout(0x3);  //read 000h
        byteout(address);
        x=bytein();
        B_SCLK5045=0;
        B_CS5045=1;
        return (x);
}

//向X5045输出单字节
void byteout(unsigned char x)
{
    unsigned char data i,j;
    j=128;
    for(i=0;i<8;i++)
    {
        B_SCLK5045=0;
        B_SI5045=x/j;
        B_SCLK5045=1;
        x%=j;
        j/=2;
    }
    B_SI5045=0;
}

//等待X5045结束内部写周期
void wip_chk()
{
    unsigned char data dat;
    tcX5045=0;
 do
    {
        dat=rdsr();
        dat&=0x1;
        if(tcX5045>=5) break;
    }
    while(dat);
}

//5045状态寄存器读出程序
unsigned char rdsr()
{
    unsigned char data dat;
 B_SCLK5045=0;
    B_CS5045=0;
    byteout(5);
 dat=bytein();
 B_SCLK5045=0;
 B_CS5045=1;
 return (dat);
}

//从X5045读出一字节数据
unsigned char bytein()
{
    unsigned char data i,x;
    x=0;
    for (i=0;i<8;i++)
    {
        B_SO5045=1;
        B_SCLK5045=1;
        B_SCLK5045=0;
        if (B_SO5045) x=x+x+1;
        else x<<=1;
    }
    return(x);
}

//5045状态寄存器写入程序
void wrsr(unsigned char x)
{
    wren();
 B_SCLK5045=0;
 B_CS5045=0;
 byteout(1);   //wrsr
 byteout(x);
 B_SCLK5045=0;
 B_CS5045=1;
 wip_chk();
    wrdi();
}

//写允许
void wren()
{
 B_SCLK5045=0;
 B_CS5045=0;
 byteout(6);
 B_SCLK5045=0;
 B_CS5045=1;
}

//写禁止
void wrdi()
{
 B_SCLK5045=0;
 B_CS5045=0;
    byteout(4);
    B_SCLK5045=0;
 B_CS5045=1;
}