Updated i2c interface to work correctly with mBed and Hexiwear
Dependents: Hexi_Click_IRThermo_Example
Fork of MLX90614 by
Diff: mlx90614.cpp
- Revision:
- 5:8f8aedd25609
- Parent:
- 2:01d333d06727
--- a/mlx90614.cpp Thu Jun 09 13:50:26 2011 +0000 +++ b/mlx90614.cpp Thu Oct 27 20:06:15 2016 +0000 @@ -1,10 +1,16 @@ - +//Melexis Infrared Thermometer MLX90614 Library + +//***************************************************************** +// Build : 27/10/16 Dave Clarke +// Only read thermo data. +// +// This program does not check CRC. +// If you want to check CRC, please do it your self :) +//****************************************************************// + #include "mlx90614.h" - - - -MLX90614::MLX90614(I2C* i2c,int addr){ +MLX90614::MLX90614(I2C* i2c, uint8_t addr){ this->i2caddress = addr; this->i2c = i2c; @@ -14,35 +20,24 @@ bool MLX90614::getTemp(float* temp_val){ - char p1,p2,p3; - float temp_thermo; - bool ch; + bool ch; // Check flag for ack + char data[3]; // Raw data storage + char ram[1] = {0x07}; // RAM address what temperature is stored + char readaddr = 0xB5; // Read Data address + uint16_t temp_thermo; + + ch = i2c->write(i2caddress, ram, 1, true); // ping i2c with address and RAM location + if (ch) return false; // check for ack + + ch = i2c->read(readaddr, data , 3); // read raw temperature value + if (ch) return false; // check for ack - i2c->stop(); //stop i2c if not ack - wait(0.01); - i2c->start(); //start I2C - ch=i2c->write(i2caddress); //device address with write condition - - if(!ch)return false; //No Ack, return False - - ch=i2c->write(0x07); //device ram address where Tobj value is present + temp_thermo |= data[1] << 8; // make MSB + temp_thermo |= data[0]; // make LSB - if(!ch)return false; //No Ack, return False + *temp_val = ((float)temp_thermo * 0.02) - 273; //Convert kelvin to degree Celsius + + return true; //load data successfully, return true +} - i2c->start(); //repeat start - ch=i2c->write(i2caddress|0x01); //device address with read condition - if(!ch)return false; //No Ack, return False - - p1=i2c->read(1); //Tobj low byte - p2=i2c->read(1); //Tobj heigh byte - p3=i2c->read(0); //PEC - - i2c->stop(); //stop condition - - - temp_thermo=((((p2&0x007f)<<8)+p1)*0.02)-0.01; //degree centigrate conversion - *temp_val=temp_thermo-273; //Convert kelvin to degree Celsius - - return true; //load data successfully, return true -} \ No newline at end of file