DS18B20 MSP430程序

MSP430高级开发板上的DS18B20温度传感器的程序

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/**********************************************************/
//MSP430 Advanced Developping Components - [DS18B20_430.C]
////DS18B20 One-Wire Digital Thermometer Demos
////->>> http://www.just430.cn
////->>> tel :(0)13500717874
/**********************************************************/
//MSP430高级实验开发组件 - DS18B20单线温度传感器示例程序
//硬件连接:
//     MSP430 Broad                    DS18B20
//   ------------------         ------------------
//   |      P23       | ------> |       DQ       |
//   ------------------         ------------------
//当前演示程序功能描述:
//循环进行温度检测,将结果分别保存在
// ResultSignal  温度符号(0x01为负)
// ResultTemperatureH 温度整数
// ResultTemperatureLH 温度小数(高两位)
// ResultTemperatureLL 温度小数(低两位)
//如果系统存在ZLG7289键盘显示模块,则可以显示温度
//**更多资料参考DS18B20数据手册以及ZLG7289_430.C
/*********************************************************/

#include 
#include "ZLG7289_430.C"

#define DS18B20_DIR  P2DIR
#define DS18B20_IN  P2IN
#define DS18B20_OUT  P2OUT

#define DS18B20_DQ  BIT3  //定义DS18B20的接口

// DS18B20 ROM命令宏定义
#define ReadRom   0x33
#define MatchRom  0x55
#define SearchRom  0xf0
#define AlertSearch  0xec
#define CopyScratchpad  0x48
#define SkipRom   0xcc
#define ReadPower  0xb4

// DS18B20 功能命令宏定义
#define ConvertTemperature 0x44
#define ReadScratchpad  0xbe
#define WriteScratchpad  0x4e
#define RecallE   0xb8

#define SMCLK   4000  //(KHz)用于<-- 2007-12-5 23:40:31-->

系统延时

// 温度的十进制编码(查表用)
unsigned char decimalH[16]={00,06,12,18,25,31,37,43,50,56,62,68,75,81,87,93};
unsigned char decimalL[16]={00,25,50,75,00,25,50,75,00,25,50,75,00,25,50,75};

// 变量定义
unsigned char GetScratchpad[9];
unsigned char ResultTemperatureH;  //温度的整数部分
unsigned char ResultTemperatureLH;  //温度的小数部分(高位)
unsigned char ResultTemperatureLL;  //温度的小数部分(低位)
 
void DS18B20_WriteBit(unsigned char oww_dat);
void DS18B20_WriteByte(unsigned char oww_dat);
void DS18B20_R eadTemp(void);
unsigned char DS18B20_Init(void);
unsigned char DS18B20_ReadBit(void);
unsigned char DS18B20_ReadByte(void);
void Delay10us(void);
void DelayX10us(unsigned char x10us);

/****************************
void main(void) {
 volatile unsigned int i,j;
 WDTCTL = WDTPW + WDTHOLD;  //停止看门狗
 
 BCSCTL1 &= ~XT2OFF;   //XT2 = HF XTAL
 do {
  IFG1 &= ~OFIFG;   //Clear OSCFault flag
  for (i=0xFF;i>0;i--);  //Time for flag to set
 }while((IFG1&OFIFG));   //OSCFault flag still set?
 BCSCTL2 |= (SELM1 + SELS);  //MCLK = SMCLK = XT2
 
 DS18B20_Init();    //初始化DS18B20
 
 Z7289_Init();
 
 while(1) {
  DS18B20_ReadTemp();
  i=ResultTemperatureH/10;
  j=ResultTemperatureH-(i*10);
  Z7289_Show(7,1,i);
  Z7289_Show(6,1,j);
  Z7289_Show(5,1,0x0C);
  i=ResultTemperatureLH/10;
  j=ResultTemperatureLH-(i*10);
  Z7289_Show(4,1,i);
  Z7289_Show(3,1,j);
  i=ResultTemperatureLL/10;
  j=ResultTemperatureLL-(i*10);
  Z7289_Show(2,1,i);
  Z7289_Show(1,1,j);
 }
}
****************************/

// 功能函数定义

unsigned char DS18B20_Init(void){
  unsigned char result;
  DS18B20_DIR |= DS18B20_DQ;       // ow output
  DS18B20_OUT &= ~DS18B20_DQ;   &<-- 2007-12-5 23:40:31-->

sp;  // DS18B20_DQ=0;
  DelayX10us(48);       // Bus master pulling low 480us minimum;
  DS18B20_OUT |= DS18B20_DQ;       // DS18B20_DQ=1;
  DelayX10us(6);        // Resister pull up 15-60us;
  DS18B20_DIR &= ~DS18B20_DQ;      // ow input
  result = DS18B20_IN & DS18B20_DQ;
  DS18B20_DIR |= DS18B20_DQ;       // ow output
  DelayX10us(48);       // End of timeslot total 480us;
  return(result);       // any 1 wire device ?result:=1 no devide; ?result:=0 have device;
}//Intialization the 1-wire devices;

unsigned char DS18B20_ReadBit(void){
  unsigned char result;
  DS18B20_DIR |= DS18B20_DQ;       // ow output
  DS18B20_OUT &= ~DS18B20_DQ;      // DS18B20_DQ=0;
  _NOP();               // Start of timeslot;
  DS18B20_OUT |= DS18B20_DQ;       // DS18B20_DQ=1;
  _NOP();_NOP();_NOP();_NOP();
          // Wait from the start;
  DS18B20_DIR &= ~DS18B20_DQ;      // ow input
  result = DS18B20_IN & DS18B20_DQ;
  DS18B20_DIR |= DS18B20_DQ;       // ow output
  return(result);       // return the result of the 1-wire devide;
}//Read a bit on the 1-wire bus;

void DS18B20_WriteBit(unsigned char oww_dat){
  DS18B20_DIR |= DS18B20_DQ;       // ow output
  DS18B20_OUT &= ~DS18B20_DQ;      // DS18B20_DQ=0;
  if (1 == oww_dat)
    DS18B20_OUT |= DS18B20_DQ;     // DS18B20_DQ=1;
  DelayX10us(10);<-- 2007-12-5 23:40:31-->

// Remain the state for 100us;
  DS18B20_OUT |= DS18B20_DQ;       // DS18B20_DQ=1;
}//Write a bit to the 1-wire bus;

unsigned char DS18B20_ReadByte(void){
  unsigned char i;
  unsigned char result="0";
  for(i = 0; i < 8; i++){
    if(DS18B20_ReadBit())
      result |= 0x01 << i;
    DelayX10us(12);     // ??
  }
  return(res ult);       // return the result of the 1-wire device;
}//Read a byte from the 1-wire bus;

void DS18B20_WriteByte(unsigned char oww_dat){
  unsigned char i,temp;
  for(i = 0; i < 8; i++){
    temp = oww_dat >> i;
    temp &= 0x01;
    DS18B20_WriteBit(temp);
  }
  DelayX10us(7);        // ??
}//Write a byte to the 1-wire bus;

void DS18B20_ReadTemp(void)
{ unsigned char tempH,tempL;
 DS18B20_Init();
 DS18B20_WriteByte(SkipRom);
 _NOP();
  //There is just one DS1820 on the bus;
 DS18B20_WriteByte(ConvertTemperature);
 DelayX10us(10);
  //Start to convert temperature;
 DS18B20_Init();
 DS18B20_WriteByte(SkipRom);
 _NOP();
 DS18B20_WriteByte(ReadScratchpad);
 GetScratchpad[0]=DS18B20_ReadByte();
  //Master samples the LSB temperature from the scratchpad;
 GetScratchpad[1]=DS18B20_ReadByte();
  //Master samples the MSB temperature from the scratchpad;
 GetScratchpad[2]=DS18B20_ReadByte();
  //Master samples the Th register or userbyte1 from the scratchpad;
 GetScratchpad[3]=DS18B20_ReadByte();
  //Master samples the Tl register or userbyte0 from the scratchpad;
 GetScratchpad[4]=DS18B20_ReadByte();
  //Master samples the configuration register from the scratchpad;
 GetScratchpad[5]=DS18B20_ReadByte();
  //Master sa<-- 2007-12-5 23:40:31-->

mples the reservedbyte from the scratchpad;
 GetScratchpad[6]=DS18B20_ReadByte();
  //Master samples the reservedbyte from the scratchpad;
 GetScratchpad[7]=DS18B20_ReadByte();
  //Master samples the reservedbyte from the scratchpad;
 GetScratchpad[8]=DS18B20_ReadByte();
  //Master samples the CRC from the scratchpad;
 tempH=(GetScratchpad[1] << 4) | (GetScratchpad[0] >> 4);
 tempL=(GetScratchpad[0] & 0x0f);
 DS18B20_Init();
&nbs p; //Issue a reset to terminate left parts;
 //if(tempH & 0x80)
 //{ tempH=~tempH;
 // tempL=~tempL+1;
 // ResultSignal=1;
 // //Negative temperature;
 //}
 ResultTemperatureH=tempH;
 ResultTemperatureLL=decimalL[tempL];
 ResultTemperatureLH=decimalH[tempL];
  //Result of temperature;
}//Read the byte0 and byte1 from scratchpad;

void Delay10us(void){
  unsigned char i;
  for (i=0; i<(SMCLK/500-3); i++);
}

//  Time is accurately !!
void DelayX10us(unsigned char x10us){
  unsigned int i;
  for (i=0; i    Delay10us();
}