Library for ADT7410 I2C temperature sensor. Use this instead of TMP102 when you need to measure temperatures lower than -40 degrees C. The device is guaranteed to work at -55 C but will actually read lower temps. See http://mbed.org/users/tkreyche/notebook/adt7140-i2c-temperature-sensor/ for more info.
Dependents: BLE_ADT7410_TMP102_Sample BLE_HTM_HRM1017 BLENano_SimpleTemplate_temp_170802 BLENano_SimpleTemplate_temp_170813 ... more
ADT7410.cpp
- Committer:
- tkreyche
- Date:
- 2011-02-01
- Revision:
- 0:380ac1ac0101
- Child:
- 8:e1aee50340ec
File content as of revision 0:380ac1ac0101:
#include "ADT7410.h" // constructor taks paramters and initializes I2C bus ADT7410::ADT7410(PinName sda, PinName scl, char addr, int hz) : i2c(sda, scl) , busAddr(addr) { i2c.frequency(hz); } // destructor ADT7410::~ADT7410() { } // read 13 bit temperature float ADT7410::getTemp() { char wReg[1] = {TEMP_REG_ADDR}; char rReg[2] = {0,0}; float tFin = 0; int tRaw = 0; // set address pointer to temperature register i2c.write(busAddr, wReg, 1); // read temperature register, two bytes i2c.read(busAddr, rReg, 2); // temperature returned is only 13 bits // discard alarm flags in lower bits tRaw = (rReg[0] << 8) | (rReg[1]); tRaw >>= 3; // handle positive and negative temperatures // results in two's complement if ( tRaw & 0x1000) { tFin = (float) (tRaw - 8192) / 16; } else { tFin = (float) tRaw / 16; } return tFin; } void ADT7410::setConfig(char regVal) { char wReg[2] = {CONFIG_REG_ADDR, regVal}; i2c.write(busAddr, wReg, 2); return; } char ADT7410::getConfig() { char rReg[1] = {0}; char wReg[1] = {CONFIG_REG_ADDR}; // need to add repeat to supress stop i2c.write(busAddr, wReg, 1, 1); i2c.read(busAddr, rReg, 1); return rReg[0]; } // reset the sensor void ADT7410::reset() { char wReg[1] = {RESET}; i2c.write(busAddr, wReg, 1); // wait for sensor to reload and convert wait_ms(250); return; }