Jens Strümper / MLX90614

Recent implementation of a MLX90614 IR temperature sensor library based on the example code of Jonathan Jones. Working with the current I2C mbed library.

Dependents:   Antarctic

MLX90614.cpp@0:755bd47fd6be, 2016-09-05 (annotated)

Committer:
jensstruemper
Date:
Mon Sep 05 10:52:54 2016 +0000
Revision:
0:755bd47fd6be
initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jensstruemper 0:755bd47fd6be 1 #include "MLX90614.h"
jensstruemper 0:755bd47fd6be 2
jensstruemper 0:755bd47fd6be 3 MLX90614::MLX90614(PinName sda, PinName scl)
jensstruemper 0:755bd47fd6be 4 {
jensstruemper 0:755bd47fd6be 5 i2c_ = new I2C(sda, scl);
jensstruemper 0:755bd47fd6be 6 i2c_->frequency(400000);
jensstruemper 0:755bd47fd6be 7 }
jensstruemper 0:755bd47fd6be 8
jensstruemper 0:755bd47fd6be 9 MLX90614::MLX90614(I2C *i2c) : i2c_(i2c) {
jensstruemper 0:755bd47fd6be 10 }
jensstruemper 0:755bd47fd6be 11
jensstruemper 0:755bd47fd6be 12 MLX90614::~MLX90614() {
jensstruemper 0:755bd47fd6be 13 delete i2c_;
jensstruemper 0:755bd47fd6be 14 }
jensstruemper 0:755bd47fd6be 15
jensstruemper 0:755bd47fd6be 16 float MLX90614::get_temp(uint8_t reg) {
jensstruemper 0:755bd47fd6be 17 char cmd[3] = { 0 };
jensstruemper 0:755bd47fd6be 18 // read the temperature data (kelvin)
jensstruemper 0:755bd47fd6be 19 cmd[0] = ram_access | reg;
jensstruemper 0:755bd47fd6be 20 i2c_->write(default_addr,cmd,1,true); i2c_->read(default_addr,cmd,3);
jensstruemper 0:755bd47fd6be 21 // convert to meaningful units, still in kelvin - just normalized
jensstruemper 0:755bd47fd6be 22 return 0.02 * static_cast<float>((cmd[1]<<8)|cmd[0]);
jensstruemper 0:755bd47fd6be 23 }
jensstruemper 0:755bd47fd6be 24
jensstruemper 0:755bd47fd6be 25 float MLX90614::read_temp(int select) {
jensstruemper 0:755bd47fd6be 26 uint8_t reg_addrs[] = { T_ambient, T_obj1 };
jensstruemper 0:755bd47fd6be 27 float tt = 0.0;
jensstruemper 0:755bd47fd6be 28 if (select == 0){
jensstruemper 0:755bd47fd6be 29 tt = get_temp(reg_addrs[0])-273.15;
jensstruemper 0:755bd47fd6be 30 }
jensstruemper 0:755bd47fd6be 31 if (select == 1){
jensstruemper 0:755bd47fd6be 32 tt = get_temp(reg_addrs[1])-273.15;
jensstruemper 0:755bd47fd6be 33 }
jensstruemper 0:755bd47fd6be 34 return tt;
jensstruemper 0:755bd47fd6be 35 }