/*
* Shtxx.h
*
* Created: 6/18/2014 2:47:58 AM
* Author: K1
*/
#ifndef SHTXX_H_
#define SHTXX_H_
#define SHT_DATA_PIN PINA
#define SHT_DATA_BIT 3
#define SHT_DATA_DDR DDRA //
#define SHT_DATA_PORT PORTA
#define SHT_DATA_IN (SHT_DATA_PIN & (1<<SHT_DATA_BIT))
#define SHT_DATA_OUT(x) (x ? (SHT_DATA_DDR |= (1<<SHT_DATA_BIT)) : (SHT_DATA_DDR &= ~(1<<SHT_DATA_BIT)) )
#define SHT_DATA(x) (x ? (SHT_DATA_PORT |= (1<<SHT_DATA_BIT)) : (SHT_DATA_PORT &= ~(1<<SHT_DATA_BIT)) )
#define SHT_SCK_BIT 4
#define SHT_SCK_DDR DDRA
#define SHT_SCK_PORT PORTA //
#define SHT_SCK(x) (x ? (SHT_SCK_PORT |= (1<<SHT_SCK_BIT)) : (SHT_SCK_PORT &= ~(1<<SHT_SCK_BIT)) )
#define SHT_SCK_OUT(x) (x ? (SHT_SCK_DDR |= (1<<SHT_SCK_BIT)) : (SHT_SCK_DDR &= ~(1<<SHT_SCK_BIT)) )
typedef union
{ unsigned int i; float f;} value;
enum {TEMP,HUMI};
#define noACK 0
#define ACK 1
//adr command r/w
#define STATUS_REG_W 0x06 //000 0011 0
#define STATUS_REG_R 0x07 //000 0011 1
#define MEASURE_TEMP 0x03 //000 0001 1
#define MEASURE_HUMI 0x05 //000 0010 1
#define RESET 0x1e //000 1111 0
const float C1=-4.0; // for 12 Bit
const float C2=+0.0405; // for 12 Bit
const float C3=-0.0000028; // for 12 Bit
const float T1=+0.01; // for 14 Bit @ 5V
const float T2=+0.00008; // for 14 Bit @ 5V
//SHT Functions
char SHT_WriteByte(unsigned char valuep);
char SHT_ReadByte(unsigned char ack);
void s_transstart(void);
void s_connectionreset(void);
char s_softreset(void);
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode);
void calc_sth11(float *p_humidity ,float *p_temperature);
float calc_dewpoint(float h,float t);
unsigned char key=16,uch_TempTime_Number=0;
int intTemp1=0,intTime1=0,intTemp2=0,intTime2=0,intTemp3=0,intTime3=0;
int intTemp4=0,intTime4=0,intTemp5=0,intTime5=0,intTemp6=0,intTime6=0;
float sht11_temp(void);
float sht11_humy(void);
void Sht11_Init(void);
#endif /* SHTXX_H_ */
/*
* Shtxx.c
*
* Created: 6/18/2014 2:49:58 AM
* Author: K1
*/
#include "Shtxx.h"
float sht11_temp()
{
value humi_val, temp_val;
unsigned char error, checksum, status;
float dew_point;
error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
if(error!=0) s_connectionreset();
else{
humi_val.f=(float)humi_val.i; //converts integer to float
temp_val.f=(float)temp_val.i; //converts integer to float
calc_sth11(&humi_val.f,&temp_val.f); //calculate humidity, temperature
dew_point=calc_dewpoint(humi_val.f,temp_val.f); //calculate dew point
}
//temp_val.f+=10;
return temp_val.f ;
}
float sht11_humy()
{
value humi_val, temp_val;
unsigned char error, checksum, status;
float dew_point;
error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
if(error!=0) s_connectionreset();
else{
humi_val.f=(float)humi_val.i; //converts integer to float
temp_val.f=(float)temp_val.i; //converts integer to float
calc_sth11(&humi_val.f,&temp_val.f); //calculate humidity, temperature
dew_point=calc_dewpoint(humi_val.f,temp_val.f); //calculate dew point
}
return humi_val.f;
}
void Sht11_Init()
{
// Setup Sensibus Pins
SHT_SCK(0); // ClockLow
SHT_SCK_DDR(1); // SCK is an output
SHT_DATAO(0); // Always Zero
s_softreset();
}
//----------------------------------------------------------------------------------
// tulis byte ke SHT
//----------------------------------------------------------------------------------
char SHT_WriteByte(unsigned char valuep)
{
// Declare your global variables here
unsigned char i,error=0;
for (i=0x80;i>0;i/=2)
{
if (i & valuep) SHT_DATA_DDR(0);
else SHT_DATA_DDR(1);
SHT_SCK(1);
_delay_us(5); //pulswith approx. 5 us
SHT_SCK(0);
}
SHT_DATA_DDR(0); //release DATA-line
SHT_SCK(1); //clk #9 for ack
error = SHT_DATA ? 1 : 0 ;//check ack (DATA will be pulled down by SHT11)
SHT_SCK(0);
return error; //error=1 in case of no acknowledge
}
//----------------------------------------------------------------------------------
// baca byte dari SHT, dan berikan ACK
//----------------------------------------------------------------------------------
char SHT_ReadByte(unsigned char ack)
{
unsigned char i,val=0;
SHT_DATA_DDR(0); //release DATA-line
for (i=0x80;i>0;i/=2)
{
SHT_SCK(1);
if (SHT_DATA) val=(val | i); //read bit
SHT_SCK(0);
}
SHT_DATA_DDR(ack); //in case of "ack==1" pull down DATA-Line
SHT_SCK(1); //clk #9 for ack
_delay_us(5); //pulswith approx. 5 us
SHT_SCK(0);
SHT_DATA_DDR(0); //release DATA-line
return val;
}
//----------------------------------------------------------------------------------
// kondisi start
// _____ ________
// DATA: |_______|
// ___ ___
// SCK : ___| |___| |______
//----------------------------------------------------------------------------------
void s_transstart(void)
{
SHT_DATA_DDR(0);
SHT_SCK(0); //Initial state
_delay_us(1);
SHT_SCK(1);
_delay_us(1);
SHT_DATA_DDR(1);
_delay_us(1);
SHT_SCK(0);
_delay_us(5);
SHT_SCK(1);
_delay_us(1);
SHT_DATA_DDR(0);
_delay_us(1);
SHT_SCK(0);
}
//----------------------------------------------------------------------------------
// reset koneksi, 9 clock diikuti dengan kondisi start
// _____________________________________________________ ________
// DATA: |_______|
// _ _ _ _ _ _ _ _ _ ___ ___
// SCK : __| |__| |__| |__| |__| |__| |__| |__| |__| |______| |___| |______
//----------------------------------------------------------------------------------
void s_connectionreset(void)
{
unsigned char i;
SHT_DATA_DDR(0); SHT_SCK(0); //Initial state
for(i=0;i<9;i++) //9 SCK cycles
{
SHT_SCK(1);
_delay_us(1);
SHT_SCK(0);
}
s_transstart(); //transmission start
}
//----------------------------------------------------------------------------------
// reset SHT-nya !!
//----------------------------------------------------------------------------------
char s_softreset(void)
{
unsigned char error=0;
s_connectionreset(); //reset communication
error+=SHT_WriteByte(RESET); //send RESET-command to sensor
return error; //error=1 in case of no response form the sensor
}
//----------------------------------------------------------------------------------
// pengukuran data
//----------------------------------------------------------------------------------
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode)
{
unsigned error=0;
long int i;
s_transstart(); //transmission start
switch(mode){ //send command to sensor
case TEMP : error+=SHT_WriteByte(MEASURE_TEMP); break;
case HUMI : error+=SHT_WriteByte(MEASURE_HUMI); break;
default : break;
}
for (i=0;i<131070;i++) if(!SHT_DATA) break; //wait until sensor has finished the measurement
if(SHT_DATA) error+=1; // or timeout (~2 sec.) is reached
*(p_value+1) =SHT_ReadByte(ACK); //read the first byte (MSB)
*(p_value) =SHT_ReadByte(ACK); //read the second byte (LSB)
*p_checksum =SHT_ReadByte(noACK); //read checksum
return error;
}
//----------------------------------------------------------------------------------------
// hitung temperature [°C] and humidity [%RH]
// input : humi [Ticks] (12 bit)
// temp [Ticks] (14 bit)
// output: humi [%RH]
// temp [°C]
//----------------------------------------------------------------------------------------
void calc_sth11(float *p_humidity ,float *p_temperature)
{
//float rh=*p_humidity; // rh: Humidity [Ticks] 12 Bit
//float t=*p_temperature; // t: Temperature [Ticks] 14 Bit
float rh_lin; // rh_lin: Humidity linear
float rh_true; // rh_true: Temperature compensated humidity
float t_C; // t_C : Temperature [°C]
t_C=*p_temperature*0.01 - 40; //calc. temperature from ticks to [°C]
rh_lin=C3*(*p_humidity)*(*p_humidity) + C2*(*p_humidity) + C1; //calc. humidity from ticks to [%RH]
rh_true=(t_C-25)*(T1+T2*(*p_humidity))+rh_lin; //calc. temperature compensated humidity [%RH]
if(rh_true>100)rh_true=100; //cut if the value is outside of
if(rh_true<0.1)rh_true=0.1; //the physical possible range
*p_temperature=t_C; //return temperature [°C]
*p_humidity=rh_true; //return humidity[%RH]
}
//--------------------------------------------------------------------
// calculates dew point
// input: humidity [%RH], temperature [°C]
// output: dew point [°C]
//--------------------------------------------------------------------
float calc_dewpoint(float h,float t)
{
float logEx,dew_point;
logEx=0.66077+7.5*t/(237.3+t)+(log10(h)-2);
dew_point = (logEx - 0.66077)*237.3/(0.66077+7.5-logEx);
return dew_point;
}
#include "app_config.h"
#define SHT_DATA_PIN PINA
#define SHT_DATA_BIT 3
#define SHT_DATA_DDR DDRA //
#define SHT_DATA_PORT PORTA
#define SHT_DATA_IN (SHT_DATA_PIN & (1<<SHT_DATA_BIT))
#define SHT_DATA_OUT(x) (x ? (SHT_DATA_DDR |= (1<<SHT_DATA_BIT)) : (SHT_DATA_DDR &= ~(1<<SHT_DATA_BIT)) )
#define SHT_DATA(x) (x ? (SHT_DATA_PORT |= (1<<SHT_DATA_BIT)) : (SHT_DATA_PORT &= ~(1<<SHT_DATA_BIT)) )
#define SHT_SCK_BIT 4
#define SHT_SCK_DDR DDRA
#define SHT_SCK_PORT PORTA //
#define SHT_SCK(x) (x ? (SHT_SCK_PORT |= (1<<SHT_SCK_BIT)) : (SHT_SCK_PORT &= ~(1<<SHT_SCK_BIT)) )
#define SHT_SCK_OUT(x) (x ? (SHT_SCK_DDR |= (1<<SHT_SCK_BIT)) : (SHT_SCK_DDR &= ~(1<<SHT_SCK_BIT)) )
typedef union
{ unsigned int i; float f;} value;
enum {TEMP,HUMI};
#define noACK 0
#define ACK 1
//adr command r/w
#define STATUS_REG_W 0x06 //000 0011 0
#define STATUS_REG_R 0x07 //000 0011 1
#define MEASURE_TEMP 0x03 //000 0001 1
#define MEASURE_HUMI 0x05 //000 0010 1
#define RESET 0x1e //000 1111 0
const float C1=-4.0; // for 12 Bit
const float C2=+0.0405; // for 12 Bit
const float C3=-0.0000028; // for 12 Bit
const float T1=+0.01; // for 14 Bit @ 5V
const float T2=+0.00008; // for 14 Bit @ 5V
//SHT Functions
char SHT_WriteByte(unsigned char valuep);
char SHT_ReadByte(unsigned char ack);
void s_transstart(void);
void s_connectionreset(void);
char s_softreset(void);
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode);
void calc_sth11(float *p_humidity ,float *p_temperature);
float calc_dewpoint(float h,float t);
float sht11_temp(void);
float sht11_humy(void);
void Sht11_Init(void);
float sht11_temp()
{
value humi_val, temp_val;
unsigned char error, checksum, status;
float dew_point;
error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
if(error!=0) s_connectionreset();
else{
humi_val.f=(float)humi_val.i; //converts integer to float
temp_val.f=(float)temp_val.i; //converts integer to float
calc_sth11(&humi_val.f,&temp_val.f); //calculate humidity, temperature
dew_point=calc_dewpoint(humi_val.f,temp_val.f); //calculate dew point
}
//temp_val.f+=10;
return temp_val.f ;
}
float sht11_humy()
{
value humi_val, temp_val;
unsigned char error, checksum, status;
float dew_point;
error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
if(error!=0) s_connectionreset();
else{
humi_val.f=(float)humi_val.i; //converts integer to float
temp_val.f=(float)temp_val.i; //converts integer to float
calc_sth11(&humi_val.f,&temp_val.f); //calculate humidity, temperature
dew_point=calc_dewpoint(humi_val.f,temp_val.f); //calculate dew point
}
return humi_val.f;
}
void Sht11_Init()
{
// Setup Sensibus Pins
SHT_SCK(0); // ClockLow
SHT_SCK_OUT(1); // SCK is an output
SHT_DATAO(0); // Always Zero
s_softreset();
}
//----------------------------------------------------------------------------------
// tulis byte ke SHT
//----------------------------------------------------------------------------------
char SHT_WriteByte(unsigned char valuep)
{
// Declare your global variables here
unsigned char i,error=0;
for (i=0x80;i>0;i/=2)
{
if (i & valuep) SHT_DATA_OUT(0);
else SHT_DATA_OUT(1);
SHT_SCK(1);
_delay_us(5); //pulswith approx. 5 us
SHT_SCK(0);
}
SHT_DATA_OUT(0); //release DATA-line
SHT_SCK(1); //clk #9 for ack
error=SHT_DATA_IN; //check ack (DATA will be pulled down by SHT11)
SHT_SCK(0);
return error; //error=1 in case of no acknowledge
}
//----------------------------------------------------------------------------------
// baca byte dari SHT, dan berikan ACK
//----------------------------------------------------------------------------------
char SHT_ReadByte(unsigned char ack)
{
unsigned char i,val=0;
SHT_DATA_OUT(0); //release DATA-line
for (i=0x80;i>0;i/=2)
{
SHT_SCK(1);
if (SHT_DATA_IN) val=(val | i); //read bit
SHT_SCK(0);
}
SHT_DATA_OUT(ack); //in case of "ack==1" pull down DATA-Line
SHT_SCK(1); //clk #9 for ack
_delay_us(5); //pulswith approx. 5 us
SHT_SCK(0);
SHT_DATA_OUT(0); //release DATA-line
return val;
}
//----------------------------------------------------------------------------------
// kondisi start
// _____ ________
// DATA: |_______|
// ___ ___
// SCK : ___| |___| |______
//----------------------------------------------------------------------------------
void s_transstart(void)
{
SHT_DATA_OUT(0);
SHT_SCK(0); //Initial state
_delay_us(1);
SHT_SCK(1);
_delay_us(1);
SHT_DATA_OUT(1);
_delay_us(1);
SHT_SCK(0);
_delay_us(5);
SHT_SCK(1);
_delay_us(1);
SHT_DATA_OUT(0);
_delay_us(1);
SHT_SCK(0);
}
//----------------------------------------------------------------------------------
// reset koneksi, 9 clock diikuti dengan kondisi start
// _____________________________________________________ ________
// DATA: |_______|
// _ _ _ _ _ _ _ _ _ ___ ___
// SCK : __| |__| |__| |__| |__| |__| |__| |__| |__| |______| |___| |______
//----------------------------------------------------------------------------------
void s_connectionreset(void)
{
unsigned char i;
SHT_DATA_OUT(0); SHT_SCK(0); //Initial state
for(i=0;i<9;i++) //9 SCK cycles
{
SHT_SCK(1);
_delay_us(1);
SHT_SCK(0);
}
s_transstart(); //transmission start
}
//----------------------------------------------------------------------------------
// reset SHT-nya !!
//----------------------------------------------------------------------------------
char s_softreset(void)
{
unsigned char error=0;
s_connectionreset(); //reset communication
error+=SHT_WriteByte(RESET); //send RESET-command to sensor
return error; //error=1 in case of no response form the sensor
}
//----------------------------------------------------------------------------------
// pengukuran data
//----------------------------------------------------------------------------------
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode)
{
unsigned error=0;
long int i;
s_transstart(); //transmission start
switch(mode){ //send command to sensor
case TEMP : error+=SHT_WriteByte(MEASURE_TEMP); break;
case HUMI : error+=SHT_WriteByte(MEASURE_HUMI); break;
default : break;
}
for (i=0;i<131070;i++) if(SHT_DATA_IN==0) break; //wait until sensor has finished the measurement
if(SHT_DATA_IN) error+=1; // or timeout (~2 sec.) is reached
*(p_value+1) =SHT_ReadByte(ACK); //read the first byte (MSB)
*(p_value) =SHT_ReadByte(ACK); //read the second byte (LSB)
*p_checksum =SHT_ReadByte(noACK); //read checksum
return error;
}
//----------------------------------------------------------------------------------------
// hitung temperature [°C] and humidity [%RH]
// input : humi [Ticks] (12 bit)
// temp [Ticks] (14 bit)
// output: humi [%RH]
// temp [°C]
//----------------------------------------------------------------------------------------
void calc_sth11(float *p_humidity ,float *p_temperature)
{
//float rh=*p_humidity; // rh: Humidity [Ticks] 12 Bit
//float t=*p_temperature; // t: Temperature [Ticks] 14 Bit
float rh_lin; // rh_lin: Humidity linear
float rh_true; // rh_true: Temperature compensated humidity
float t_C; // t_C : Temperature [°C]
t_C=*p_temperature*0.01 - 40; //calc. temperature from ticks to [°C]
rh_lin=C3*(*p_humidity)*(*p_humidity) + C2*(*p_humidity) + C1; //calc. humidity from ticks to [%RH]
rh_true=(t_C-25)*(T1+T2*(*p_humidity))+rh_lin; //calc. temperature compensated humidity [%RH]
if(rh_true>100)rh_true=100; //cut if the value is outside of
if(rh_true<0.1)rh_true=0.1; //the physical possible range
*p_temperature=t_C; //return temperature [°C]
*p_humidity=rh_true; //return humidity[%RH]
}
//--------------------------------------------------------------------
// calculates dew point
// input: humidity [%RH], temperature [°C]
// output: dew point [°C]
//--------------------------------------------------------------------
float calc_dewpoint(float h,float t)
{
float logEx,dew_point;
logEx=0.66077+7.5*t/(237.3+t)+(log10(h)-2);
dew_point = (logEx - 0.66077)*237.3/(0.66077+7.5-logEx);
return dew_point;
}
/*
* Shtxx.h
*
* Created: 6/18/2014 2:47:58 AM
* Author: K1
*/
#ifndef SHTXX_H_
#define SHTXX_H_
#include "app_config.h"
//#define SHT_DATA_OUT DDRA.3
//#define SHT_DATA_IN PINA.3
//#define SHT_SCK PORTA.4
#define SHT_DATA_PIN PINA
#define SHT_DATA_BIT 3
#define SHT_DATA_DDR DDRA //
#define SHT_DATA_PORT PORTA
#define SHT_DATA_IN (SHT_DATA_PIN & (1<<SHT_DATA_BIT))
#define SHT_DATA_OUT(x) (x ? (SHT_DATA_DDR |= (1<<SHT_DATA_BIT)) : (SHT_DATA_DDR &= ~(1<<SHT_DATA_BIT)) )
#define SHT_DATA(x) (x ? (SHT_DATA_PORT |= (1<<SHT_DATA_BIT)) : (SHT_DATA_PORT &= ~(1<<SHT_DATA_BIT)) )
#define SHT_SCK_BIT 4
#define SHT_SCK_DDR DDRA
#define SHT_SCK_PORT PORTA //
#define SHT_SCK(x) (x ? (SHT_SCK_PORT |= (1<<SHT_SCK_BIT)) : (SHT_SCK_PORT &= ~(1<<SHT_SCK_BIT)) )
#define SHT_SCK_OUT(x) (x ? (SHT_SCK_DDR |= (1<<SHT_SCK_BIT)) : (SHT_SCK_DDR &= ~(1<<SHT_SCK_BIT)) )
typedef struct
{ unsigned int i; float f;} value;
enum {TEMP,HUMI};
#define noACK 0
#define ACK 1
//adr command r/w
#define STATUS_REG_W 0x06 //000 0011 0
#define STATUS_REG_R 0x07 //000 0011 1
#define MEASURE_TEMP 0x03 //000 0001 1
#define MEASURE_HUMI 0x05 //000 0010 1
#define RESET 0x1e //000 1111 0
const float C1=-4.0; // for 12 Bit
const float C2=+0.0405; // for 12 Bit
const float C3=-0.0000028; // for 12 Bit
const float T1=+0.01; // for 14 Bit @ 5V
const float T2=+0.00008; // for 14 Bit @ 5V
//SHT Functions
char SHT_WriteByte(unsigned char valuep);
char SHT_ReadByte(unsigned char ack);
void s_transstart(void);
void s_connectionreset(void);
char s_softreset(void);
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode);
void calc_sth11(float *p_humidity ,float *p_temperature);
float calc_dewpoint(float h,float t);
float sht11_temp(void);
float sht11_humy(void);
void Sht11_Init(void);
float sht11_temp()
{
value humi_val, temp_val;
unsigned char error, checksum, status;
float dew_point;
error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
if(error!=0) s_connectionreset();
else{
humi_val.f=(float)humi_val.i; //converts integer to float
temp_val.f=(float)temp_val.i; //converts integer to float
calc_sth11(&humi_val.f,&temp_val.f); //calculate humidity, temperature
dew_point=calc_dewpoint(humi_val.f,temp_val.f); //calculate dew point
}
//temp_val.f+=10;
return temp_val.f ;
}
float sht11_humy()
{
value humi_val, temp_val;
unsigned char error, checksum, status;
float dew_point;
error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
if(error!=0) s_connectionreset();
else{
humi_val.f=(float)humi_val.i; //converts integer to float
temp_val.f=(float)temp_val.i; //converts integer to float
calc_sth11(&humi_val.f,&temp_val.f); //calculate humidity, temperature
dew_point=calc_dewpoint(humi_val.f,temp_val.f); //calculate dew point
}
return humi_val.f;
}
void Sht11_Init()
{
// Setup Sensibus Pins
SHT_SCK(0); // ClockLow
SHT_SCK_OUT(1); // SCK is an output
SHT_DATA(0); // Always Zero
s_softreset();
}
//----------------------------------------------------------------------------------
// tulis byte ke SHT
//----------------------------------------------------------------------------------
char SHT_WriteByte(unsigned char valuep)
{
// Declare your global variables here
unsigned char i,error=0;
for (i=0x80;i>0;i/=2)
{
if (i & valuep) SHT_DATA_OUT(0);
else SHT_DATA_OUT(1);
SHT_SCK(1);
_delay_us(5); //pulswith approx. 5 us
SHT_SCK(0);
}
SHT_DATA_OUT(0); //release DATA-line
SHT_SCK(1); //clk #9 for ack
error=SHT_DATA_IN; //check ack (DATA will be pulled down by SHT11)
SHT_SCK(0);
return error; //error=1 in case of no acknowledge
}
//----------------------------------------------------------------------------------
// baca byte dari SHT, dan berikan ACK
//----------------------------------------------------------------------------------
char SHT_ReadByte(unsigned char ack)
{
unsigned char i,val=0;
SHT_DATA_OUT(0); //release DATA-line
for (i=0x80;i>0;i/=2)
{
SHT_SCK(1);
if (SHT_DATA_IN) val=(val | i); //read bit
SHT_SCK(0);
}
SHT_DATA_OUT(ack); //in case of "ack==1" pull down DATA-Line
SHT_SCK(1); //clk #9 for ack
_delay_us(5); //pulswith approx. 5 us
SHT_SCK(0);
SHT_DATA_OUT(0); //release DATA-line
return val;
}
//----------------------------------------------------------------------------------
// kondisi start
// _____ ________
// DATA: |_______|
// ___ ___
// SCK : ___| |___| |______
//----------------------------------------------------------------------------------
void s_transstart(void)
{
SHT_DATA_OUT(0);
SHT_SCK(0); //Initial state
_delay_us(1);
SHT_SCK(1);
_delay_us(1);
SHT_DATA_OUT(1);
_delay_us(1);
SHT_SCK(0);
_delay_us(5);
SHT_SCK(1);
_delay_us(1);
SHT_DATA_OUT(0);
_delay_us(1);
SHT_SCK(0);
}
//----------------------------------------------------------------------------------
// reset koneksi, 9 clock diikuti dengan kondisi start
// _____________________________________________________ ________
// DATA: |_______|
// _ _ _ _ _ _ _ _ _ ___ ___
// SCK : __| |__| |__| |__| |__| |__| |__| |__| |__| |______| |___| |______
//----------------------------------------------------------------------------------
void s_connectionreset(void)
{
unsigned char i;
SHT_DATA_OUT(0); SHT_SCK(0); //Initial state
for(i=0;i<9;i++) //9 SCK cycles
{
SHT_SCK(1);
_delay_us(1);
SHT_SCK(0);
}
s_transstart(); //transmission start
}
//----------------------------------------------------------------------------------
// reset SHT-nya !!
//----------------------------------------------------------------------------------
char s_softreset(void)
{
unsigned char error=0;
s_connectionreset(); //reset communication
error+=SHT_WriteByte(RESET); //send RESET-command to sensor
return error; //error=1 in case of no response form the sensor
}
//----------------------------------------------------------------------------------
// pengukuran data
//----------------------------------------------------------------------------------
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode)
{
unsigned error=0;
long int i;
s_transstart(); //transmission start
switch(mode){ //send command to sensor
case TEMP : error+=SHT_WriteByte(MEASURE_TEMP); break;
case HUMI : error+=SHT_WriteByte(MEASURE_HUMI); break;
default : break;
}
for (i=0;i<131070;i++) if(SHT_DATA_IN==0) break; //wait until sensor has finished the measurement
if(SHT_DATA_IN) error+=1; // or timeout (~2 sec.) is reached
*(p_value+1) =SHT_ReadByte(ACK); //read the first byte (MSB)
*(p_value) =SHT_ReadByte(ACK); //read the second byte (LSB)
*p_checksum =SHT_ReadByte(noACK); //read checksum
return error;
}
//----------------------------------------------------------------------------------------
// hitung temperature [°C] and humidity [%RH]
// input : humi [Ticks] (12 bit)
// temp [Ticks] (14 bit)
// output: humi [%RH]
// temp [°C]
//----------------------------------------------------------------------------------------
void calc_sth11(float *p_humidity ,float *p_temperature)
{
//float rh=*p_humidity; // rh: Humidity [Ticks] 12 Bit
//float t=*p_temperature; // t: Temperature [Ticks] 14 Bit
float rh_lin; // rh_lin: Humidity linear
float rh_true; // rh_true: Temperature compensated humidity
float t_C; // t_C : Temperature [°C]
t_C=*p_temperature*0.01 - 40; //calc. temperature from ticks to [°C]
rh_lin=C3*(*p_humidity)*(*p_humidity) + C2*(*p_humidity) + C1; //calc. humidity from ticks to [%RH]
rh_true=(t_C-25)*(T1+T2*(*p_humidity))+rh_lin; //calc. temperature compensated humidity [%RH]
if(rh_true>100)rh_true=100; //cut if the value is outside of
if(rh_true<0.1)rh_true=0.1; //the physical possible range
*p_temperature=t_C; //return temperature [°C]
*p_humidity=rh_true; //return humidity[%RH]
}
//--------------------------------------------------------------------
// calculates dew point
// input: humidity [%RH], temperature [°C]
// output: dew point [°C]
//--------------------------------------------------------------------
float calc_dewpoint(float h,float t)
{
float logEx,dew_point;
logEx=0.66077+7.5*t/(237.3+t)+(log10(h)-2);
dew_point = (logEx - 0.66077)*237.3/(0.66077+7.5-logEx);
return dew_point;
}
#endif /* SHTXX_H_ */
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