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
Revision 0:380ac1ac0101, committed 2011-02-01
- Comitter:
- tkreyche
- Date:
- Tue Feb 01 18:57:41 2011 +0000
- Child:
- 1:257d9e026cc4
- Commit message:
Changed in this revision
ADT7410.cpp | Show annotated file Show diff for this revision Revisions of this file |
ADT7410.h | Show annotated file Show diff for this revision Revisions of this file |
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ADT7410.cpp Tue Feb 01 18:57:41 2011 +0000 @@ -0,0 +1,73 @@ +#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; +} +
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ADT7410.h Tue Feb 01 18:57:41 2011 +0000 @@ -0,0 +1,105 @@ +/* +Copyright (c) 2011 Tom Kreyche tkreyche@well.com + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. +*/ + +/** Servo control class, based on a PwmOut +* +* Example: +* @code + +#include "mbed.h" +#include "ADT7410.h" + +ADT7410 tempSens1(p28, p27, 0x90, 100000); + +int main() { + + // reset sensor to default values + tempSens1.reset(); + + // read the config register, should be default + printf("Config: 0x%x\n", tempSens1.getConfig()); + + // reduce sample rate to save power + tempSens1.setConfig(ONE_SPS_MODE); + + // check config register was set correctly + printf("Config: 0x%x\n", tempSens1.getConfig()); + + // get temperature every two seconds + while (1) { + + printf("Deg C %f\n", tempSens1.getTemp()); + wait(2); + } +} + +* @endcode +*/ + +#ifndef ADT7410_H +#define ADT7410_H + +#include "mbed.h" + +// sensor register addresses +// only a partial list, don't use them all +#define TEMP_REG_ADDR 0x00 +#define CONFIG_REG_ADDR 0x03 +#define RESET 0x2F + +// configuration register values +// only a partial list, don't use them all +#define ONE_SPS_MODE 0x40 + +//Library for the ADT7410 temperature sensor + +class ADT7410 +{ + +public: + + // Creates an instance of the class. + // Connect module at I2C address addr using I2C port pins sda and scl + ADT7410(PinName sda, PinName scl, char addr, int hz); + + //Destroys instance. + ~ADT7410(); + + //Reads the current temperature. + float getTemp(); + + //Set config register + void setConfig(char regVal); + + //Get config register + char getConfig(); + + //Send reset + void reset(); + +private: + I2C i2c; + char busAddr; + +}; + +#endif