test_TMP102.cpp

00001 #include "test_TMP102.h"
00002 
00003 test_TMP102::test_TMP102(PinName sda, PinName scl, char address)
00004     : i2c_p(new I2C(sda, scl)), i2c(*i2c_p),adr(address)
00005 {
00006     init();
00007 }
00008 test_TMP102::test_TMP102(I2C &i2c_obj, char address)
00009     : i2c_p(NULL), i2c(i2c_obj), adr(address)
00010 {
00011     init();
00012 }
00013 
00014 test_TMP102::~test_TMP102()
00015 {
00016     if(NULL!=i2c_p)
00017         delete i2c_p;
00018 }
00019 
00020 void test_TMP102::init(void)
00021 {
00022 }
00023 
00024 float test_TMP102::read(void)
00025 {
00026     char reg[2]= {0,0};
00027     char pointer = TMP102_Temp;
00028     i2c.write(adr, &pointer, 1); //Pointer to the temperature register
00029     i2c.read(adr, reg, 2); // read two bytes data
00030 
00031     int16_t res;
00032     // Bit 0 of second byte will always be 0 in 12-bit readings and 1 in 13-bit
00033     if(reg[1]&0x01)  // 13 bit mode
00034     {
00035         // combine bytes to create a signed int
00036         res = ((int8_t)reg[0] << 5) | ((uint8_t)reg[1] >> 3);
00037         // Temperature data can be + or -, if it should be negative,
00038         // convert 13 bit to 16 bit and use the 2s compliment.
00039         if (res > 0xFFF) res |= 0xE000;
00040     } else  // 12 bit mode
00041     {
00042         res = ((int8_t)reg[0] << 4) | ((uint8_t)reg[1] >> 4);
00043         if (res > 0x7FF) res |= 0xF000;
00044     }
00045     
00046     float temp = (float)(res * 0.0625);
00047     return temp;
00048 }
00049 
00050 float test_TMP102::readTempC(void)
00051 {
00052     return read();
00053 }
00054 
00055 float test_TMP102::readTempF(void)
00056 {
00057     return (float)((double)readTempC()*9.0/5.0 + 32.0);
00058 }
00059 
00060 void test_TMP102::setConversionRate(char rate)
00061 {
00062     char reg[2] = {0, 0};
00063     char pointer = TMP102_Conf;
00064     rate = rate & 0x03;              // make sure rate is not set higher than 3.
00065     
00066     i2c.write(adr, &pointer, 1);    //Pointer to the conf register
00067     i2c.read(adr, reg, 2);          // read two bytes data
00068     
00069     reg[1] &= 0x3F;         // Clear CR0/1 (bit 6 and 7 of second byte)
00070     reg[1] |= rate << 6;    // Shift in new conversion rate
00071     
00072     char data[3];
00073     data[0] = pointer;
00074     data[1] = reg[0];
00075     data[2] = reg[1];
00076     i2c.write(adr, data, 3);
00077 }
00078 
00079 void test_TMP102::setExtendedMode(bool mode)
00080 {
00081     char reg[2] = {0, 0};
00082     char pointer = TMP102_Conf;
00083     
00084     i2c.write(adr, &pointer, 1);    //Pointer to the conf register
00085     i2c.read(adr, reg, 2);          // read two bytes data
00086     
00087     reg[1] &= 0xEF;     // Clear EM (bit 4 of second byte)
00088     reg[1] |= mode<<4;  // Shift in new exentended mode bit
00089     
00090     char data[3];
00091     data[0] = pointer;
00092     data[1] = reg[0];
00093     data[2] = reg[1];
00094     i2c.write(adr, data, 3);
00095 }
00096 
00097 test_TMP102::operator float(void)
00098 {
00099     return (read());
00100 }
00101 
00102 void test_TMP102::sleep(void)
00103 {
00104     char reg;
00105     char pointer = TMP102_Conf;
00106     i2c.write(adr, &pointer, 1); //Pointer to the conf register
00107     i2c.read(adr, &reg, 1); // read one byte data
00108     
00109     reg |= 0x01;            // set SD (bit 0 of first byte)
00110     
00111     char data[2];
00112     data[0] = pointer;
00113     data[1] = reg;
00114     i2c.write(adr, data, 2);
00115 }
00116 
00117 void test_TMP102::wakeup(void)
00118 {
00119     char reg;
00120     char pointer = TMP102_Conf;
00121     i2c.write(adr, &pointer, 1); //Pointer to the conf register
00122     i2c.read(adr, &reg, 1); // read one byte data
00123     
00124     reg &= 0xFE;    // Clear SD (bit 0 of first byte)
00125     
00126     char data[2];
00127     data[0] = pointer;
00128     data[1] = reg;
00129     i2c.write(adr, data, 2);
00130 }
00131 
00132 void test_TMP102::oneShot(void)
00133 {
00134     char reg;
00135     char pointer = TMP102_Conf;
00136     i2c.write(adr, &pointer, 1); //Pointer to the conf register
00137     i2c.read(adr, &reg, 1); // read one byte data
00138     
00139     reg |= 0x80;    // Set OS (bit 7 of first byte)
00140     
00141     char data[2];
00142     data[0] = pointer;
00143     data[1] = reg;
00144     i2c.write(adr, data, 2);
00145     
00146     do {
00147         wait(0.026);
00148         i2c.read(adr, &reg, 1);
00149         reg &= 0x80;
00150     } while (reg == 0);
00151 }