//从ds18b20得到温度值
//精度：0.1C
//返回值：温度值 （-550~1250）
short DS18B20_Get_Temp(void)
{
u8 temp;
u8 TL,TH;
short tem;
DS18B20_Start (); // ds1820 start convert
DS18B20_Rst();
DS18B20_Check();
DS18B20_Write_Byte(0xcc);// skip rom
DS18B20_Write_Byte(0xbe);// convert
TL=DS18B20_Read_Byte(); // LSB
TH=DS18B20_Read_Byte(); // MSB
if(TH>7)
{
TH=~TH;
TL=~TL;
temp=0;//温度为负
}else temp=1;//温度为正
tem=TH; //获得高八位
tem<<=8;
tem+=TL;//获得底八位
tem=(float)tem*0.625;//转换
if(temp)return tem; //返回温度值
else return -tem;
}
//开始温度转换
void DS18B20_Start(void)// ds1820 start convert
{
DS18B20_Rst();
DS18B20_Check();
DS18B20_Write_Byte(0xcc);// skip rom
DS18B20_Write_Byte(0x44);// convert
}
short DS18B20_Get_Temp(u8 ch)
{
u8 temp;
u8 TL,TH;
short tem;
u32 ads[8]={0x186e0d3b,0x182d843b,0x186e743b,0x186b0c3b,0x1873ba3b,0x1835163b,0x1834fa3b,0x1873983b};
u32 crc[8]={0x7f000000,0xa4000000,0x71000000,0x9a000000,0x6d000000,0x39000000,0xa0000000,0xb5000000};
DS18B20_Rst();
DS18B20_Check();
delay_us(50);
DS18B20_Write_Byte(0x55);
delay_us(10);
DS18B20_Write_Addr(ads[ch],crc[ch]);
delay_us(10);
DS18B20_Write_Byte(0xbe);// convert
TL=DS18B20_Read_Byte(); // LSB
TH=DS18B20_Read_Byte(); // MSB
if(TH>7)
{
TH=~TH;
TL=~TL;
temp=0;//negative
}else temp=1;//positive
tem=TH; //Hreg
tem<<=8;
tem+=TL;//Lreg
tem=(float)tem*0.625;//convert
if(temp)return tem; //return
else return -tem;
}
//UPDATE:
//修正输出值分辨率，修改返回属性为double
//从ds18b20得到温度值
//精度：0.0625C
//返回值：温度值 （-55~125）
double DS18B20_Get_Temp(void)
{
u8 zhengfu;
u8 TL,TH;
short temRaw;
double finalTemp;
DS18B20_Start (); // ds1820 start convert
DS18B20_Rst();
DS18B20_Check();
DS18B20_Write_Byte(0xcc);// skip rom
DS18B20_Write_Byte(0xbe);// convert
TL=DS18B20_Read_Byte(); // LSB
TH=DS18B20_Read_Byte(); // MSB
if(TH>7)
{
TH=~TH;
TL=~TL;
zhengfu=0;//温度为负
}else zhengfu=1;//温度为正
temRaw=TH; //获得高八位
temRaw<<=8;
temRaw+=TL;//获得底八位
finalTemp=(double)temRaw*0.0625;//转换
return zhengfu?finalTemp:-finalTemp;
}
//return 1:does not excist
//0 excist
u8 DS18B20_Init(void)
{
RCC->APB2ENR|=1<<2;
GPIOA->CRL=3<<0;
GPIOA->ODR|=1<<0;
DS18B20_Rst();
return DS18B20_Check();
}
void startconv()
{
TIM2->DIER&=0<<6;
TIM2->DIER&=0<<0; //allow update interrupt
DS18B20_Rst();
DS18B20_Check();
delay_us(50);
DS18B20_Write_Byte(0xcc);
delay_us(10);
DS18B20_Write_Byte(0x44);// convert
TIM2->DIER|=1<<6; //allow update interrupt
TIM2->DIER|=1<<0;
delay_ms(75);
}
u8 DS18B20_Init(void)
{
RCC->APB2ENR|=1<<2; //使能PORTA口时钟 //wl
DS18B20_IO_OUT();//PORTA.0 推挽输出 //wl
GPIOA->ODR|=1; //输出1 //wl
DS18B20_Rst();
return DS18B20_Check();
}
//初始化DS18B20的IO口 DQ 同时检测DS的存在
//返回1:不存在
//返回0:存在
u8 DS18B20_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(DS18B20_APB, ENABLE); //使能PORTG口时钟
GPIO_InitStructure.GPIO_Pin = DS18B20_PIN; //PORTG.11 推挽输出
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(DS18B20_PORT, &GPIO_InitStructure);
GPIO_SetBits(DS18B20_PORT,DS18B20_PIN); //输出1
DS18B20_Rst();
return DS18B20_Check();
}
//初始化DS18B20的IO口 DQ 同时检测DS的存在
//返回1:不存在
//返回0:存在
u8 ds18b20_init(void)
{
//GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(DS_RCC, ENABLE); //使能PORTB口时钟
GPIO_InitStructure.GPIO_Pin = DS_PIN; //PORTB3 推挽输出
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
GPIO_SetBits(DS_GPIO,DS_PIN); //输出1
DS18B20_Rst();
return DS18B20_Check();
}
//初始化DS18B20的IO口 DQ 同时检测DS的存在
//返回1:不存在
//返回0:存在
u8 DS18B20_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能PORTG口时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11; //PORTG.11 推挽输出
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_SetBits(GPIOA,GPIO_Pin_11); //输出1
DS18B20_Rst();
return DS18B20_Check();
}
u8 OWSearch(u8 *newAddr)
{
u8 id_bit_number;
u8 last_zero, rom_byte_number, search_result;
u8 id_bit, cmp_id_bit;
int i;
unsigned char rom_byte_mask, search_direction;
static unsigned char ROM_NO[8];
static u32 LastDiscrepancy = 0;
static u8 LastDeviceFlag = FALSE;
static u32 LastFamilyDiscrepancy = 0;
// initialize for search
id_bit_number = 1;
last_zero = 0;
rom_byte_number = 0;
rom_byte_mask = 1;
search_result = 0;
// if the last call was not the last one
if (!LastDeviceFlag)
{
// 1-Wire reset
DS18B20_Rst();
if(DS18B20_Check())
{
// reset the search
LastDiscrepancy = 0;
LastDeviceFlag = FALSE;
LastFamilyDiscrepancy = 0;
return FALSE;
}
// issue the search command
DS18B20_Write_Byte(0xF0);
// loop to do the search
do
{
// read a bit and its complement
id_bit = DS18B20_Read_Bit();
cmp_id_bit = DS18B20_Read_Bit();
// check for no devices on 1-wire
if ((id_bit == 1) && (cmp_id_bit == 1))
break;
else
{
// all devices coupled have 0 or 1
if (id_bit != cmp_id_bit)
search_direction = id_bit; // bit write value for search
else
{
// if this discrepancy if before the Last Discrepancy
// on a previous next then pick the same as last time
if (id_bit_number < LastDiscrepancy)
search_direction = ((ROM_NO[rom_byte_number] & rom_byte_mask) > 0);
else
// if equal to last pick 1, if not then pick 0
search_direction = (id_bit_number == LastDiscrepancy);
// if 0 was picked then record its position in LastZero
if (search_direction == 0)
{
last_zero = id_bit_number;
// check for Last discrepancy in family
if (last_zero < 9)
LastFamilyDiscrepancy = last_zero;
}
}
// set or clear the bit in the ROM byte rom_byte_number
// with mask rom_byte_mask
if (search_direction == 1)
ROM_NO[rom_byte_number] |= rom_byte_mask;
else
ROM_NO[rom_byte_number] &= ~rom_byte_mask;
// serial number search direction write bit
OWWrite_bit(search_direction);
// increment the byte counter id_bit_number
// and shift the mask rom_byte_mask
id_bit_number++;
rom_byte_mask <<= 1;
// if the mask is 0 then go to new SerialNum byte rom_byte_number and reset mask
if (rom_byte_mask == 0)
{
rom_byte_number++;
rom_byte_mask = 1;
}
}
}
while(rom_byte_number < 8); // loop until through all ROM bytes 0-7
// if the search was successful then
if (!(id_bit_number < 65))
{
// search successful so set LastDiscrepancy,LastDeviceFlag,search_result
LastDiscrepancy = last_zero;
// check for last device
if (LastDiscrepancy == 0)
LastDeviceFlag = TRUE;
search_result = TRUE;
}
}
// if no device found then reset counters so next 'search' will be like a first
if (!search_result || !ROM_NO[0])
{
LastDiscrepancy = 0;
LastDeviceFlag = FALSE;
LastFamilyDiscrepancy = 0;
search_result = FALSE;
}
for (i = 0; i < 8; i++) newAddr[i] = ROM_NO[i];
return search_result;
}