Revision 0:fdb750cc9ca8, committed 2018-10-06

Comitter:

shivanandgowdakr

Date:

Sat Oct 06 12:08:55 2018 +0000

Commit message:

HDC1080 Temperature Humidity Sensor ; i2c based or controlled ;

Changed in this revision

diff -r 000000000000 -r fdb750cc9ca8 HDC1080.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/HDC1080.cpp	Sat Oct 06 12:08:55 2018 +0000
@@ -0,0 +1,143 @@
+
+#include "mbed.h"
+#include "HDC1080.h"
+
+#define     HDC_TEMP_OFF        0x00
+#define     HDC_HUMID_OFF       0x01
+#define     HDC_CONFIG_OFF      0x02
+#define     HDC_MANID_OFF       0xFE
+#define     HDC_SER_OFF_FIRST   0xFB
+#define     HDC_SER_OFF_MID     0xFC
+#define     HDC_SER_OFF_LAST    0xFD
+#define     I2C_FREQ            100000
+#define     CHIP_ADDRESS        (0x40 << 1)   // left shift 1 bit for 7 bit address required by
+
+ // Shift by one bit to get 7 bit I2C Addrress
+char HDC_COMMN = HDC_MANID_OFF;
+const float HDC_CHIP_ERROR = -255;
+const unsigned long HDC_CHIP_SER_ERROR = 0;
+char Buffer[5];
+
+
+HDC1080::HDC1080(PinName sda, PinName slc) : I2C(sda,slc) 
+{
+    memset(Buffer,'\0',5);
+    Buffer[0] = HDC_CONFIG_OFF;
+    this->frequency(I2C_FREQ);
+    int res = this->write(CHIP_ADDRESS, Buffer, 2);
+    printf("HDC Constructor Initialization  : Res =%d\r\n", res);
+}
+
+  int HDC1080::ReadSignature(void)
+{ 
+    
+uint16_t  Manufacturer_ID = read2Bytes(CHIP_ADDRESS, HDC_MANID_OFF);
+    if (Manufacturer_ID == 0) {
+     
+        printf("Error  reading HDC Manufacturer ID\r\n");
+       
+        return (int) HDC_CHIP_ERROR;
+    } else {  
+           
+        printf("Manufacturer_ID  :%x\r\n", (int) Manufacturer_ID);
+      
+        return Manufacturer_ID;
+    }    
+}  
+    
+    
+    
+    
+    
+ float HDC1080::readTemperature()
+{
+    uint16_t  rawT = read2Bytes(CHIP_ADDRESS, HDC_TEMP_OFF);
+    if (rawT == 0) {
+       
+        printf("error in reading  chip Temp\r\n");
+       
+        return HDC_CHIP_ERROR;
+    } else {
+        float temp = ((float) rawT / pow(2.0f, 16.0f)) * 165.0f - 40.0f;
+        
+        printf("Temperature   : %0.3f\r\n", temp);
+        
+        return temp;
+    }
+}   
+    
+       
+    
+ float HDC1080::readHumidity()
+{
+    uint16_t  rawH = read2Bytes(CHIP_ADDRESS, HDC_HUMID_OFF);
+    if (rawH == 0) {
+       
+        printf("error in reading  chip Temp\r\n");
+       
+        return HDC_CHIP_ERROR;
+    } else {
+        float humidity = ((float) rawH / pow(2.0f, 16.0f)) * 100.0f;
+        
+        printf("Humidity   : %0.3f\r\n", humidity);
+        
+        return humidity;
+    }
+}   
+    
+    unsigned long HDC1080::readSerialNumber(void)
+{    
+    wait(0.015);
+    memset(Buffer,0,4);
+    Buffer[0] = HDC_MANID_OFF;
+    int res = this->write(CHIP_ADDRESS, Buffer, 1);
+    if (res != 0) {      
+     
+      printf("Error writing chip addr res=%d\r\n", res);
+    
+      return (unsigned long) HDC_CHIP_SER_ERROR;
+    }      
+ 
+    wait(0.015);
+    memset(Buffer,0,4);
+    res = this->read(CHIP_ADDRESS, Buffer,4);
+    if (res != 0) {
+     
+      printf("Errot reading chip serial res=%d#\r\n", res);
+     
+      return (unsigned long) HDC_CHIP_SER_ERROR;
+    }
+      
+//    unsigned long rawser = Buffer[0] << 16 | Buffer[1] << 8 | Buffer[0];
+      unsigned long rawser = Buffer[2] << 16 | Buffer[1] << 8 | Buffer[0];
+  
+    printf("Serial Number is =%lu\r\n", rawser);
+   
+    return rawser;
+}
+    
+    
+    //Private Member functions 
+    
+    uint16_t HDC1080::read2Bytes(int chip_addr, int offset)
+{
+    memset(Buffer,0,3);
+    // send chip address onto buss
+    Buffer[0] = offset;
+    int res =this->write(chip_addr, Buffer, 1);
+    if (res != 0) {
+       
+        printf("error Communicating  to chip %d offst=%d\r\n", chip_addr, offset);
+       
+        return 0;
+    }
+    // read data from chip
+    wait(0.015);
+    memset(Buffer,0,3);
+    res = this->read(CHIP_ADDRESS, Buffer,2);
+    if (res != 0) {
+        printf("error Communicating to  chip %d offst=%d\r\n", chip_addr, offset);
+        return 0;
+    }
+    return  Buffer[0] << 8 | Buffer[1];
+}

diff -r 000000000000 -r fdb750cc9ca8 HDC1080.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/HDC1080.h	Sat Oct 06 12:08:55 2018 +0000
@@ -0,0 +1,30 @@
+
+#ifndef HDC1080_H
+#define HDC1080_H
+
+ 
+ 
+
+
+
+class HDC1080:public I2C {
+public:
+   
+
+    
+    HDC1080( PinName sda, PinName slc) ;                 // constructor
+
+//    ~HDC1080();                                          // destructor
+
+    int ReadSignature(void);
+    float readTemperature( void);                   // to read the Temperature from HDC1080 
+    float readHumidity(void);                       // to read the Humidity from HDC1080
+    unsigned long readSerialNumber(void);            // to read the Humidity from HDC1080
+
+protected:
+     uint16_t read2Bytes(int chip_addr, int offset);
+};
+
+#endif
+
+