MLX90614.cpp

00001 #include "MLX90614.h"
00002 
00003 MLX90614::MLX90614(PinName sda, PinName scl)
00004 {
00005     i2c_ = new I2C(sda, scl);
00006     i2c_->frequency(400000);
00007 }
00008 
00009 MLX90614::MLX90614(I2C *i2c) : i2c_(i2c) {
00010     }
00011 
00012 MLX90614::~MLX90614() {
00013     delete i2c_;
00014     }
00015 
00016 float MLX90614::get_temp(uint8_t reg) {
00017     char cmd[3] = { 0 };
00018     // read the temperature data (kelvin)
00019     cmd[0] = ram_access | reg;
00020     i2c_->write(default_addr,cmd,1,true); i2c_->read(default_addr,cmd,3);
00021     // convert to meaningful units, still in kelvin - just normalized
00022     return 0.02 * static_cast<float>((cmd[1]<<8)|cmd[0]);
00023 }
00024 
00025 float MLX90614::read_temp(int select) {
00026     uint8_t reg_addrs[] = { T_ambient, T_obj1 };
00027     float tt = 0.0;
00028     if (select == 0){
00029         tt = get_temp(reg_addrs[0])-273.15;
00030         }
00031     if (select == 1){
00032         tt = get_temp(reg_addrs[1])-273.15;
00033         }
00034     return tt;
00035     }