#include "basic.h"
 
 
void Delay_Times(int d)
{
   int m = 0,n = 0;
	for(m = 0; m < d;m++)
	{
		for(n=0 ; n < 10; n++);
	}
}	

 
 /***********************************************
调用方式：MAX31865_Init()
返回值：
SDO   --->   PB14
CS    --->   PB12
SCLK  --->   PB13
SDI   --->   PB15
DRDY  --->   PD8
函数说明：MAX31865 初始化,软件模拟
************************************************/
void MAX31865_Init(void)
{
	GPIO_InitTypeDef GPIO_InitStructure ;
 
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB|RCC_AHB1Periph_GPIOD, ENABLE);
 
	GPIO_InitStructure.GPIO_Pin = MAX31865_CS|MAX31865_SCLK|MAX31865_SDI;
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_OUT;           //输出模式
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;          //推挽输出
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ;       
	GPIO_Init(MAX31865_CONTROL_PORT,&GPIO_InitStructure);
	
	GPIO_InitStructure.GPIO_Pin = MAX31865_SDO;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;  //配置输入模式为上拉输入
	GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
	GPIO_Init(MAX31865_CONTROL_PORT,&GPIO_InitStructure);
	
	GPIO_InitStructure.GPIO_Pin = MAX31865_DRDY;
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN;  //配置输入模式为上拉输入
	GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
	GPIO_Init(MAX31865_DRDYL_PORT,&GPIO_InitStructure);
	
	MAX31865_CS_SET;
	MAX31865_SCLK_SET;
}
 
/***********************************************
调用方式：MAX31865_Write()
返回值：
函数说明：MAX31865 写寄存器,addr:寄存器地址,data:数据
************************************************/
void MAX31865_Write(unsigned char addr, unsigned char data)
{
	unsigned char i;
	MAX31865_CS_CLR;
//	MAX31865_SCLK_SET;
	 Delay_Times(20);
	for(i=0;i<8;i++)  //写地址
	{
		MAX31865_SCLK_CLR;
		//Delay_Times(50);
		if(addr & 0x80) 
			MAX31865_SDI_SET;
		else 
			MAX31865_SDI_CLR;    	
		Delay_Times(20);
		MAX31865_SCLK_SET;
		addr <<= 1;
		Delay_Times(20);
	}
	
	Delay_Times(20);
	
	for(i=0;i<8;i++)  //写数据
	{
		MAX31865_SCLK_CLR;
		//Delay_Times(50);
		if(data & 0x80) 
			MAX31865_SDI_SET;
		else 
			MAX31865_SDI_CLR;
		Delay_Times(20);		
		MAX31865_SCLK_SET;	
		data <<= 1;	
		Delay_Times(20);

	}
	MAX31865_CS_SET;
	//Delay_Times(20);
}
/***********************************************
调用方式：MAX31865_Read()
返回值：  data
函数说明：MAX31865 读寄存器 ,addr:寄存器地址
************************************************/
unsigned char MAX31865_Read(unsigned char addr)
{
	unsigned char i;
	unsigned char data=0;
	MAX31865_CS_CLR;
//  MAX31865_SCLK_SET;
	Delay_Times(20);
	for(i=0;i<8;i++)  //写地址
	{
	    MAX31865_SCLK_CLR;
		//Delay_Times(50);	
		if(addr&0x80)
			MAX31865_SDI_SET;
		else 
			MAX31865_SDI_CLR;
		Delay_Times(20);	
		MAX31865_SCLK_SET;
		addr <<= 1;
		Delay_Times(20);
	}
	
    Delay_Times(20);

	for(i=0;i<8;i++)  //读数据
	{
		MAX31865_SCLK_CLR;
		Delay_Times(20);
		data <<= 1;
		MAX31865_SCLK_SET;							
		if(MAX31865_SDO_READ)
			//data++;			
			data|=0x01;
		else 
			data|=0x00;	
			
		Delay_Times(20);
	}
	MAX31865_CS_SET;
	//Delay_Times(20);
	return data;
}
/***********************************************
调用方式：MAX31865_Cfg()
返回值：  
函数说明：MAX31865 配置
************************************************/
void MAX31865_Cfg(void)
{
	//BIAS ON,自动，4线，50HZ  根据文件修改四线还是三线
	MAX31865_Write(0x80, 0xD1); 
}
/***********************************************
调用方式：MAX31865_GetTemp()
返回值：  
函数说明：MAX31865 获取温度
************************************************/
float MAX31865_GetTemp(void)
{ 
	unsigned int data = 0;
	float Rt;
	float Rt0 = 100;  //PT100	
	float Z1,Z2,Z3,Z4,temp;
	float a = 3.9083e-3;
	float b = -5.775e-7;
	float rpoly;
	//MAX31865_Write(0x80, 0xD3);
	data  = MAX31865_Read(0x01) << 8;
	data |= MAX31865_Read(0x02);
	data>>=1;  //去掉Fault位
	//printf("Read=0x%02X\r\n",data);
	Rt=(float)data/32768.0f*RREF;
	//printf("Rt=0x%.1f\r\n",Rt);
	Z1 = -a;
	Z2 = a*a-4*b;
	Z3 = 4*b/Rt0;
	Z4 = 2*b;
	temp = Z2+Z3*Rt;
	temp = (sqrt(temp)+Z1)/Z4;
	if(temp>=0)
	{
		return temp;
	}
	rpoly = Rt;
	temp = -242.02;
	temp += 2.2228f * rpoly;
	rpoly *= Rt;  // square
	temp += 2.5859e-3f * rpoly;
	rpoly *= Rt;  // ^3
	temp -= 4.8260e-6f * rpoly;
	rpoly *= Rt;  // ^4
	temp -= 2.8183e-8f * rpoly;
	rpoly *= Rt;  // ^5
	temp += 1.5243e-10f * rpoly;
 
    return temp;
}