SHT31D calculation problem

Code C - [expand]
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#include <stdio.h>
#include <stdlib.h>
 
//helpful types
#define bool unsigned char
#define false 0
#define true  1
#define byte unsigned char
 
//I2C definitons
#define I2C_WRITE         0
#define I2C_READ          1
 
// Assuming default I2C address (ADDR pin 2 connected to VSS)
#define SHT3X    (0x44 << 1)
 
// Assume clock stretching disabled (not sure what this I2C library can manage!)
#define SHT3X_CMD_MSB_START_MEAS   0x24
 
// Assume medium repeatability (measurement time, current consumption, etc.)
#define SHT3X_CMD_LSB_START_MEAS   0x0B
 
// Assuming CPU clock speed 8MHz, 1 CPU clock cycle per loop (will be more!),
// this will give a delay > 20ms. Note: worst case conversion time is 15ms.
#define SHT3X_MEAS_DELAY_LOOP_VAL  160000
 
  // Lcd connections
sbit LCD_RS at RB4_bit;
sbit LCD_EN at RB5_bit;
sbit LCD_D4 at RB0_bit;
sbit LCD_D5 at RB1_bit;
sbit LCD_D6 at RB2_bit;
sbit LCD_D7 at RB3_bit;
 
sbit LCD_RS_Direction at TRISB4_bit;
sbit LCD_EN_Direction at TRISB5_bit;
sbit LCD_D4_Direction at TRISB0_bit;
sbit LCD_D5_Direction at TRISB1_bit;
sbit LCD_D6_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB3_bit;
Lcd_Init();
 
 
 
// Start temperature and humidity measurement
bool Sht3xStartMeasurement()
{
  bool error = false;
  I2C1_Start();
  I2C1_Wr(SHT3X + I2C_WRITE);
  I2C1_Wr(SHT3X_CMD_MSB_START_MEAS);
  I2C1_Wr(SHT3X_CMD_LSB_START_MEAS);
  I2C1_Stop();                                            // issue I2C stop signal
 
  return error;
}
 
 
 
bool Sht3xReadMeasurementResult(unsigned short* pTemperature, unsigned short* pHumidity)
{
  bool error   = false;
  byte tempMsb = 0;
  byte tempLsb = 0;
  byte tempCrc = 0;
  byte humMsb  = 0;
  byte humLsb  = 0;
  byte humCrc  = 0;
 
  I2C1_Start();                                         // issue I2C start signal
  I2C1_Wr(SHT3X + I2C_READ);                             // send byte via I2C  (device address + R)
  I2C1_Repeated_Start();                                  // issue I2C repeated start signal
 
  tempMsb = I2C1_Rd(1);                                   // Read the data (acknowledge)
  tempLsb = I2C1_Rd(1);                                   // Read the data (acknowledge)
  tempCrc = I2C1_Rd(1);                                   // Read the data (acknowledge)
  humMsb  = I2C1_Rd(1);                                   // Read the data (acknowledge)
  humLsb  = I2C1_Rd(1);                                   // Read the data (acknowledge)
  humCrc  = I2C1_Rd(0);                                   // Read the data (NO acknowledge)
 
  I2C1_Stop();                                            // issue I2C stop signal
 
 
  *pTemperature = (tempMsb << 8) + tempLsb;
  *pHumidity    = (humMsb  << 8) + humLsb;
 
  return error;
}
 
 
 
bool Sht3xStatusRegRead_temperature(unsigned short* pStatus)
{
  bool error  = false;
  byte regMsb = 0;
  byte regLsb = 0;
  byte crc    = 0;
 
  I2C1_Start();                                // issue I2C start signal
  I2C1_Wr(SHT3X + I2C_WRITE);         // send byte via I2C  (device address + W)
  I2C1_Wr(0xF3);                              // send byte (command msb)
  I2C1_Wr(0x2D);                               // send byte (command lsb)
 
  I2C1_Repeated_Start();                                  // issue I2C repeated start signal
  I2C1_Wr(SHT3X + I2C_READ);         // send byte via I2C  (device address + R)
 
  regMsb = I2C1_Rd(1);                                   // Read the data (acknowledge)
  regLsb = I2C1_Rd(1);                                   // Read the data (acknowledge)
  crc    = I2C1_Rd(0);                                   // Read the data (NO acknowledge)
 
  I2C1_Stop();
 
  *pStatus = (regMsb << 8) + regLsb;
 
  return error;
}
 
 
 
bool Sht3xStatusRegClear()
{
  bool error = false;
 
  I2C1_Start();                                // issue I2C start signal
  I2C1_Wr(SHT3X + I2C_WRITE);        // send byte via I2C  (device address + W)
  I2C1_Wr(0x30);                             // send byte (command msb)
  I2C1_Wr(0x41);                               // send byte (command lsb)
 
  I2C1_Stop();
 
  return error;
}
 
void check_device(unsigned short dev_address){
 I2C1_Start();
 if (I2C1_Wr(dev_address)){
  Lcd_Out(1,1,"Device not found");
 }
 else Lcd_Out(1,1,"SHT31D");
  I2C1_Stop();
}
 
    unsigned long i = 0;
    unsigned short temperature;
    unsigned short humidity;
    char temp[8];
    char hum[8];
    unsigned short value;
    //char snum[6];
 
void main()
{
OSCCON=0x00;
TRISC3_BIT=1;   //CLK
TRISC4_BIT=1;  //SDA
ADCON1 = 15;           //All PINS TO digital
SSPCON1=0x28;       // SDA & SCL port serial &clock = fosc/(4*(sspadd+1))
SSPCON2=0x00;
SSPSTAT=0x00;
SSPADD=0x27;        //baud rate 39 in decimal
 
        // Cursor off
     Lcd_Init();          // Initialize LCD
  delay_ms(50);
  Lcd_Cmd(_LCD_CLEAR);             // CLEAR display
  Lcd_Cmd(_LCD_CURSOR_OFF);
    ShortToStr(temperature, temp);
    ShortToStr(humidity, hum);
    Lcd_Out(1,2, temp);
    Lcd_Out(2,2, hum);
    Delay_ms(200);
  
 
    for(;;){
    //check_device(SHT3X + I2C_WRITE);
    Sht3xStatusRegClear();
    Sht3xStartMeasurement();
    for (i = 0; i < SHT3X_MEAS_DELAY_LOOP_VAL; i++); // delay
    Sht3xReadMeasurementResult(&temperature, &humidity);
    Sht3xStatusRegRead_temperature(&value);
 
    temperature = (-45 + (175*256))/65535;
    humidity = (100*(256))/65535;
 
    }
}