Are SHT11 & 18S20 sensors able to work together ?
Posted: 13 Feb 2010 10:39
Hello,
Has someone already be able to have Sensirion sensor SHTxx + Dallas 18S20 displaying temperatures on a LCD ?
I have 2 working codes for :
SHT11
and
18S20
They are both working well separatly but when i try to combine the codes into ONE project, i can't get it working.
In fact, I would like to have SHT11 temp & humidity datas displayed on a LCD and also 18S20 temp displayed on another LCD row.
It is possible ?
If someone can post a working example i will really appreciate it.
Many thanks for your help,
Has someone already be able to have Sensirion sensor SHTxx + Dallas 18S20 displaying temperatures on a LCD ?
I have 2 working codes for :
SHT11
and
18S20
They are both working well separatly but when i try to combine the codes into ONE project, i can't get it working.
In fact, I would like to have SHT11 temp & humidity datas displayed on a LCD and also 18S20 temp displayed on another LCD row.
It is possible ?
If someone can post a working example i will really appreciate it.
Many thanks for your help,
Code: Select all
/*******************************************************************************
CompiLED by: Mikro C v8.0.0.0
PIC 16F876A @ 4MHz.
Description: SHT11 + DS18S20 :
Pins configuration :
- SHT11 SCK on RC4
- SHT11 Data on RC5
- 18S20 on RC0
LCD on port B :
- RS on RB2
- E on RB3
- D4 on RB4
- D5 on RB5
- D6 on RB6
- D7 on RB7
*******************************************************************************/
// Adding a Custom LCD character : °C
const char degre[] = {8,20,8,0,3,4,4,3};
void symbol_degre(char pos_row, char pos_char) {
char i;
LCD_Cmd(64);
for (i = 0; i<=7; i++) LCD_Chr_Cp(degre[i]);
LCD_Cmd(LCD_RETURN_HOME);
LCD_Chr(pos_row, pos_char, 0);}
typedef union
{ unsigned int i;
float f;
} value;
//////////////////////////
// Adding 18S20 code :
// Set temp_dallas_RESOLUTION to the corresponding resolution of your DS18x20 sensor:
// 18S20: 9
// 18B20: 12 (default setting; can be 9,10,11,or 12)
const unsigned short temp_dallas_RESOLUTION = 9;
const int RES_FACTOR_1[4] = {5000, 2500, 1250, 625};
const unsigned int RES_FACTOR_2[4] = {0x0001, 0x0003, 0x0007, 0x000F};
const unsigned int RES_FACTOR_3[4] = {0x8000, 0xC000, 0xE000, 0xF000};
float alarma;
unsigned temp_dallas,temp_dallas2,new_temp_dallas;
unsigned short j, RES_SHIFT,j2;
///////////////////DISPLAY FOR ONE DEVICE//////////////////
void Display_temp_dallas(unsigned int temp_dallas) {
const unsigned short RES_SHIFT = temp_dallas_RESOLUTION - 8;
unsigned int temp_dallas_whole, temp_dallas_fraction;
unsigned short i;
char text[8];
// Isolate the fraction and make it a 4-digit decimal integer (for display)
temp_dallas_fraction = temp_dallas & RES_FACTOR_2[RES_SHIFT - 1];
temp_dallas_fraction = temp_dallas_fraction * RES_FACTOR_1[RES_SHIFT - 1];
//portc = temp_dallas_fraction;
// Handle the whole part of temp_dallaserature value
temp_dallas_whole = temp_dallas;
// Is temp negative?
if ((temp_dallas_whole & 0x8000) != 0u) i = 1; // Yes, i = 1
else i = 0; // No, i = 0
PORTC = i;
// Remove the fractional part
temp_dallas_whole >>= RES_SHIFT;
// Correct the sign if necessary
if (i) temp_dallas_whole |= RES_FACTOR_3[RES_SHIFT - 1];
//portd = temp_whole;
IntToStr(temp_dallas_whole, text); // Convert whole part to string
Lcd_Out(4, 10, text); // Print whole part on LCD
Lcd_Chr_Cp('.'); // Print dot to separate fractional part
IntToStr(temp_dallas_fraction, text); // Convert fractional part to string
// Add leading zeroes (we display 4 digits fractional part)
if (temp_dallas_fraction < 1000u) Lcd_Chr_Cp('0');
if (temp_dallas_fraction < 100u) Lcd_Chr_Cp('0');
if (temp_dallas_fraction < 10u) Lcd_Chr_Cp('0');
Lcd_Out_Cp(text); // Print fractional part on LCD
Lcd_Chr_Cp(223); // Print degree character
Lcd_Chr_Cp('C'); // Print 'C' for Centigrades
}//~
// End code 18S20
//////////////////////////
// Added for AN reading :
unsigned int hold;
char txt[7];
//////////////////////////
// Init SHT 11 :
//------------------------------------------------------------------------------
// modul-var
//------------------------------------------------------------------------------
//enum {TEMP,HUMI};
#define TEMP 0
#define HUMI 1
// SHT sensor : RC4:data - RC5:SCK
#define PORT_COND TRISC.F4 //data port condition: input/output
#define DATA PORTC.F4 //SHT11 DATA pin
#define SCK PORTC.F5 //STH11 SCK pin
#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
#define MEMORY_ADDRESS 0xA0
// Definition for Inputs & Outputs :
#define BP PORTC.F6 // BP on RC6 ( input )
#define LED1 PORTC.F1 // LED1 on RC1 ( output )
#define LED2 PORTC.F2 // LED2 on RC2 ( output )
#define LED3 PORTC.F3 // LED3 on RC3 ( output )
//#define BP1 PORTA.F0 // BP1 on RA0 ( input )
/************************************************************
Initializations
************************************************************/
void Init(void)
{
TRISA = 0xFF; //PORTA as input
ADCON1 = 0x0E; // Set AN0 channel pin as analog
CMCON |= 7; // Disable comparators
PORTB = 0x00; //initialize PORTB
TRISB = 0;
Lcd_Init(&PORTB);
Lcd_Cmd(LCD_CLEAR); // Clear display
Lcd_Cmd(LCD_CURSOR_OFF); // Turn cursor off
PORTC = 0x00;
TRISC = 0B00000001; // RC0 = input - RC1 - RC7 = outputs
}
//------------------------------------------------------------------------------
char s_write_byte(unsigned char value)
//------------------------------------------------------------------------------
// writes a byte on the Sensibus and checks the acknowLED1ge
{
unsigned char i,error=0;
PORT_COND = 0; //SHT11 WRITE
for (i=0x80;i>0;i/=2) //shift bit for masking
{
Delay_us(2);
if (i & value)
DATA=1; //masking value with i , write to SENSI-BUS
else
DATA=0;
SCK=1; //clk for SENSI-BUS
Delay_us(2); //pulswith approx. 5 us
SCK=0;
}
DATA=1; //release DATA-line
PORT_COND = 1; //SHT11 READ
Delay_us(2);
SCK=1; //clk #9 for ack
Delay_us(2);
error = DATA; //check ack (DATA will be pulLED1 down by SHT11)
SCK=0;
return error; //error=1 in case of no acknowLED1ge
}
//----------------------------------------------------------------------------------
char s_read_byte(unsigned char ack)
//----------------------------------------------------------------------------------
// reads a byte form the Sensibus and gives an acknowLED1ge in case of "ack=1"
{
unsigned char i,val=0;
PORT_COND = 1; //SHT11 READ
DATA=1; //release DATA-line
for (i=0x80;i>0;i/=2) //shift bit for masking
{
Delay_us(2);
SCK=1; //clk for SENSI-BUS
if (DATA) val=(val | i); //read bit
Delay_us(2);
SCK=0;
}
Delay_us(2);
PORT_COND = 0; //SHT11 WRITE
Delay_us(2);
DATA=!ack; //in case of "ack==1" pull down DATA-Line
SCK=1; //clk #9 for ack
Delay_us(2); //pulswith approx. 5 us
SCK=0;
Delay_us(2);
DATA=1; //release DATA-line
return val;
}
//----------------------------------------------------------------------------------
void s_transstart(void)
//----------------------------------------------------------------------------------
// generates a transmission start
// _____ ________
// DATA: |_______|
// ___ ___
// SCK : ___| |___| |______
{
PORT_COND = 0; //SHT11 WRITE
DATA=1;
SCK=0; //Initial state
Delay_us(2);
SCK=1;
Delay_us(2);
DATA=0;
Delay_us(2);
SCK=0;
Delay_us(2);
SCK=1;
Delay_us(2);
DATA=1;
Delay_us(2);
SCK=0;
}
//----------------------------------------------------------------------------------
void s_connectionreset(void)
//----------------------------------------------------------------------------------
// communication reset: DATA-line=1 and at least 9 SCK cycles followed by transstart
// _____________________________________________________ ________
// DATA: |_______|
// _ _ _ _ _ _ _ _ _ ___ ___
// SCK : __| |__| |__| |__| |__| |__| |__| |__| |__| |______| |___| |______
{
unsigned char i;
PORT_COND = 0; //SHT11 WRITE
DATA=1; SCK=0; //Initial state
for(i=0;i<9;i++) //9 SCK cycles
{
Delay_us(2);
SCK=1;
Delay_us(2);
SCK=0;
}
Delay_us(2);
s_transstart(); //transmission start
}
//----------------------------------------------------------------------------------
char s_softreset(void)
//----------------------------------------------------------------------------------
// resets the sensor by a softreset
{
unsigned char error=0;
s_connectionreset(); //reset communication
error+=s_write_byte(RESET); //send RESET-command to sensor
return error; //error=1 in case of no response form the sensor
}
//----------------------------------------------------------------------------------
char s_read_statusreg(unsigned char *p_value, unsigned char *p_checksum)
//----------------------------------------------------------------------------------
// reads the status register with checksum (8-bit)
{
unsigned char error=0;
s_transstart(); //transmission start
error=s_write_byte(STATUS_REG_R); //send command to sensor
//Delay_us(100);
*p_value=s_read_byte(ACK); //read status register (8-bit)
*p_checksum=s_read_byte(noACK); //read checksum (8-bit)
return error; //error=1 in case of no response form the sensor
}
//----------------------------------------------------------------------------------
char s_write_statusreg(unsigned char *p_value)
//----------------------------------------------------------------------------------
// writes the status register with checksum (8-bit)
{
unsigned char error=0;
s_transstart(); //transmission start
error+=s_write_byte(STATUS_REG_W);//send command to sensor
error+=s_write_byte(*p_value); //send value of status register
return error; //error>=1 in case of no response form the sensor
}
//----------------------------------------------------------------------------------
char s_measure(unsigned char *p_value, unsigned char *p_checksum, unsigned char mode)
//----------------------------------------------------------------------------------
// makes a measurement (humidity/temperature) with checksum
{
unsigned error=0;
unsigned int i;
s_transstart(); //transmission start
switch(mode)
{ //send command to sensor
case TEMP : error+=s_write_byte(MEASURE_TEMP); break; //temp
case HUMI : error+=s_write_byte(MEASURE_HUMI); break; //humidity
default : break;
}
PORT_COND = 1; //SHT11 READ
for (i = 0; i < 65535 && DATA; i++) Delay_us(10); //wait until sensor has finished the measurement
//while (DATA == 1) Delay_us(1);
if(DATA) error+=1; // or timeout (~2 sec.) is reached
*(p_value+1)=s_read_byte(ACK); //read the second byte (LSB)
*(p_value) =s_read_byte(ACK); //read the first byte (MSB)
*p_checksum =s_read_byte(noACK); //read checksum
return error;
}
/*
//----------------------------------------------------------------------------------
void init_uart()
//----------------------------------------------------------------------------------
// Initializes the UART so the final data can be sent away, e.g. to a PC
//9600 bps @ 11.059 MHz
{ SCON = 0x52;
TMOD = 0x20;
TCON = 0x69;
TH1 = 0xfd;
}
*/
//----------------------------------------------------------------------------------------
void calc_sth11(float *p_humidity ,float *p_temperature)
//----------------------------------------------------------------------------------------
// calculates temperature [C] and humidity [%RH]
// input : humi [Ticks] (12 bit)
// temp [Ticks] (14 bit)
// output: humi [%RH]
// temp [C]
{ 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
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=t*0.01-40; //calc. Temperature from ticks to [C]
rh_lin=C3*rh*rh + C2*rh + C1; //calc. Humidity from ticks to [%RH]
rh_true=(t_C-25)*(T1+T2*rh)+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]
}
//--------------------------------------------------------------------
float calc_dewpoint(float h,float t)
//--------------------------------------------------------------------
// calculates dew point
// input: humidity [%RH], temperature [C]
// output: dew point [C]
{ float k,dew_point ;
k = (log10(h)-2)/0.4343 + (17.62*t)/(243.12+t);
dew_point = 243.12*k/(17.62-k);
return dew_point;
}
//----------------------------------------------------------------------------------
void main()
//----------------------------------------------------------------------------------
{
// SHT 11 management :
// sample program that shows how to use SHT11 functions
// 1. connection reset
// 2. measure humidity [ticks](12 bit) and temperature [ticks](14 bit)
// 3. calculate humidity [%RH] and temperature [C]
// 4. calculate dew point [C]
// 5. print temperature, humidity, dew point
value humi_val,temp_val;
float dew_point;
unsigned char error,checksum;
//unsigned int i;
char temp[13];
char humi[13];
char dew[13];
Init(); //Initialize LCD & Pins
s_connectionreset();
Delay_ms(20);
while(1)
{
error=0;
error+=s_measure((unsigned char*) &humi_val.i,&checksum,HUMI);
//measure humidity
error+=s_measure((unsigned char*) &temp_val.i,&checksum,TEMP);
//measure temperature
if(error!=0) s_connectionreset(); //in case of an error: connection reset
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
//send final data to serial interface (UART)
//Lcd_Out(1,1,Out_temp());
Lcd_Out(1,1,("Temp ext"));
FloatToStr(temp_val.f, temp);
Lcd_Out(1,11,temp);
symbol_degre(1,16);
Lcd_Out(2,1,("H"));
FloatToStr(humi_val.f, humi);
Lcd_Out(2,3,humi);
Lcd_Out(2,8,("%"));
// Ajout semble fonctionner :
Lcd_Out(2,9,(" Dp "));
FloatToStr(dew_point, dew);
Lcd_Out(2,13,dew);
}
// start Code 18S20
////////////////// RESET DEVICE 1///////////////////
Ow_Reset(&PORTC,0); // Onewire reset signal
Ow_Write(&PORTC,0,0xCC); // Issue command SKIP_ROM
Ow_Write(&PORTC,0,0x44); // Issue command CONVERT_T
Delay_us(120);
Ow_Reset(&PORTC,0);
Ow_Write(&PORTC,0,0xCC); // Issue command SKIP_ROM
Ow_Write(&PORTC,0,0xBE); // Issue command READ_SCRATCHPAD
Delay_ms(400);
/*******************************************************/
///////////// 18S20 TEMPERATURE DISPLAY ///////////////////
j = Ow_Read(&PORTC,0); // Get temperature LSB
temp_dallas = Ow_Read(&PORTC,0); // Get temperature MSB
temp_dallas <<= 8; temp_dallas += j; // Form the result
Lcd_Out(4,8,"Cabin Temp");
Display_temp_dallas(temp_dallas); // Format and display result on LCD
//Delay_ms(500);
// end CODE 18S20
//----------wait approx. 0.8s to avoid heating up SHTxx----------------------
//-----------------------------------------------------------------------------------
Delay_ms(1500);
}
}