//-----------------------------------------------------------------
// 名称: SPI接口温度传感器TC72应用测试
//-----------------------------------------------------------------
// 说明: 本例运行时,单片机将持续从TC72传感器读取温度数据并转换为
// 浮点型字符串送LCD显示(内置SPI接口需要在实物电路测试)
//
//-----------------------------------------------------------------
#include "REG51RX2.H"
#include <intrins.h>
#include <stdio.h>
#include <math.h>
#define INT8U unsigned char
#define INT16U unsigned int
//SPI使能与禁用(注意TC72是高电平使能,低电平禁用)
#define SPI_EN() P1 |= (1<<4)
#define SPI_DI() P1 &= ~(1<<4)
//TC72寄存器地址定义
#define TC72_CTRL 0x80 //控制寄存器
#define TC72_TEMP_LSB 0x01 //温度低字节
#define TC72_TEMP_MSB 0x02 //温度高字节
#define TC72_MANU_ID 0x03 //制造商ID
//SPI接口引脚定义(模拟方式)
sbit SCK = P3^4; //串行时钟
sbit CE = P3^5; //片选
sbit SDI = P3^6; //串行数据输入
sbit SDO = P3^7; //串行数据输出
//内置SPI寄存器及寄存器位定义
//SPCON C3h SPI Control SPR2 SPEN SSDIS MSTR CPOL CPHA SPR1 SPR0
//SPSTA C4h SPI Status SPIF WCOL SSERR MODF - - - -
//SPDAT C5h SPI Data SPD7 SPD6 SPD5 SPD4 SPD3 SPD2 SPD1 SPD0
//sfr SPCON = 0xC3;
//sfr SPSTA = 0xC4;
//sfr SPDAT = 0xC5;
//extern void Initialize_LCD();
extern void LCD_ShowString(INT8U r, INT8U c,INT8U *str);
extern void delay_ms(INT16U x);
INT8U T[2]; //两字节原始温度数据
float TempX = 0.0; //浮点温度值
//-----------------------------------------------------------------
// SPI主机初始化
//-----------------------------------------------------------------
//void SPI_MasterInit()
//{
// SPCON=0xD0;
// SPSTA=0xC0;
//}
//-----------------------------------------------------------------
// SPI数据传输
//-----------------------------------------------------------------
//INT8U SPI_SendData(INT8U dat)
//{
// SPDAT=dat;
// while((SPSTA&0x80)==0x00);
// SPSTA=0xC0;
// return SPDAT;
//}
//-----------------------------------------------------------------
// 从当前地址读取一字节数据(模拟方式)
//-----------------------------------------------------------------
INT8U ReadByte()
{
INT8U i,d=0x00;
for(i=0;i<8;i++)
{
SCK=1;
SCK=0;
d=(d<<1)|SDO;
}
return d;
}
//-----------------------------------------------------------------
// 向当前地址写入一字节数据(模拟方式)
//-----------------------------------------------------------------
void WriteByte(INT8U dat)
{
INT8U i;
for(i=0;i<8;i++)
{
SCK=0;
dat<<=1;
SDI=CY;
SCK=1;
}
}
//-----------------------------------------------------------------
// 向TC72写入两字节(地址,数据)(模拟方式)
//-----------------------------------------------------------------
void Write_TC72(INT8U addr, INT8U dat)
{
CE=1;
WriteByte(addr);
WriteByte(dat);
CE=0;
}
//-----------------------------------------------------------------
// 写TC72配置数据
//-----------------------------------------------------------------
void Config_TC72()
{
Write_TC72(TC72_CTRL,0x15);
}
//-----------------------------------------------------------------
// 从TC72读取两字节温度数据并转换为浮点温度值
//-----------------------------------------------------------------
void Read_TC72_Temperature()
{
Config_TC72();
delay_ms(20);
CE=1;
WriteByte(TC72_TEMP_MSB);
T[1]=ReadByte();
T[0]=ReadByte();
CE=0;
TempX=(((int)((T[1]<<8)|T[0]))>>6)*0.25;
}
//-----------------------------------------------------------------
// 主程序
//-----------------------------------------------------------------
void main()
{
char DisplayBuffer[17];
Initialize_LCD();
LCD_ShowString(0,0,"TC72 Sensor Test");
while(1)
{ Config_TC72();
Read_TC72_Temperature();
sprintf(DisplayBuffer,"%TEMP:%6.1f\xDF\x43",TempX);
LCD_ShowString(1,0,DisplayBuffer);
}
}
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