@ScruffR, Thank you ScruffR. I was thinking that I’d need to get into the DFU business in order to recover from the solid blue state. I appreciate your help in getting me back in the game. I ordered another backup Photon to keep around just in case. 
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Good day, I have copied and pasted your code but the reading of my MLX 90614 IS -273C AND -459.68.
heres the code 
// This #include statement was automatically added by the Particle IDE.
#include <OneWire.h>
// This #include statement was automatically added by the Particle IDE.
#include <Adafruit_MLX90614.h>
#define LED_pin D7
#define slaveAddress 0x5A
void setup(){
Serial.begin(9600);
// An LED will blink to indicate when we have successfully read the temperature
pinMode(LED_pin, OUTPUT);
digitalWrite(LED_pin, LOW);
Wire.begin();
Wire.beginTransmission(slaveAddress);
}
void loop(){
// Store the two relevant bytes of data for temperature
byte dataLow = 0x00;
byte dataHigh = 0x00;
delay(10);
Wire.write(0x07); // This is the command to view object temperature in the sensor's RAM
delay(10);
Wire.endTransmission(false);
delay(10);
Wire.requestFrom(slaveAddress, 2);
delay(10);
while (Wire.available()){
dataLow = Wire.read();
dataHigh = Wire.read();
digitalWrite(LED_pin, HIGH); // Blink the LED to indicate a successful reading
}
delay(10);
digitalWrite(LED_pin, LOW);
double tempFactor = 0.02; // 0.02 degrees per LSB (measurement resolution of the MLX90614)
double tempData = 0x0000; // zero out the data
// This masks off the error bit of the high byte, then moves it left 8 bits and adds the low byte.
tempData = (double)(((dataHigh & 0x007F) << 8) + dataLow);
tempData = (tempData * tempFactor)-0.01;
float celcius = tempData - 273.15;
float fahrenheit = (celcius*1.8) + 32;
Serial.print((String) fahrenheit);
Serial.println("F");
Serial.print((String) celcius);
Serial.println("C");
Spark.publish ( "celcius", String(celcius) + "C");
Spark.publish ( "fahrenheit", String(fahrenheit) + "F");
delay(10000);
}
I want also to know the connections of this sensor because i think maybe there also something wrong with it.
I just bought my photon particle recently and I’m not so good in programming.
Thanks in advanced.
hubeltran.
Hello any example how to use multiple sparkfun ML90614 sensors, i got running code with MLX90614 library on sparkfun nrf52xxx board and wondering if anybody done multiple sensors with AVR and wire lib. thanks
@Racoon, you do know that this is a forum for Particle devices, right? However, since the MLX90614 has no programmable addresses, only one can be addressed at a time on the I2C bus. One way to do this is using an I2C multiplexer chip like the TI TCA9544A or the Maxim MAX7368EUE+. Each MLX90614 would occupy one of the multiplexed channels so they don’t clash.
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No you not right i can program and change address just AVR works with Wire lib. and my changes what i am doing with I2c lib. looking help with wire lib. Thanks
// remap_mlx90614.ino
#include "i2cmaster.h"
// New slave address, purposefully left shifted
byte NewMLXAddr = 0x5D;
// 0x5A is the default address - uncomment this to set it back
// byte NewMLXAddr = 0x5A;
void setup(){
Serial.begin(9600);
Serial.println("Setup...");
// Initialise the i2c bus, enable pullups and then wait
i2c_init();
PORTC = (1 << PORTC4) | (1 << PORTC5);
delay(5000);
// Read current address bytes
ReadAddr(0);
// Change address to new value (NewMLXAddr);
ChangeAddr(NewMLXAddr, 0x00);
// Read address bytes
ReadAddr(0);
Serial.print("> Cycle power NOW to set address to: ");
Serial.print(NewMLXAddr, HEX);
Serial.println(" - you have 10 seconds");
// Cycle power to MLX during this 10 second pause
delay(10000);
// Read temperature using default address
ReadTemp(0);
// Read temperature using new address (note left bit shift for reading)
ReadTemp(NewMLXAddr<<1);
Serial.println("**---DONE---**");
}
void loop(){
delay(5000);
ReadTemp(NewMLXAddr<<1);
}
word ChangeAddr(byte NewAddr1, byte NewAddr2) {
Serial.println("> Change address");
// Send start condition and write bit
i2c_start_wait(0 + I2C_WRITE);
// Send command for device to return address
i2c_write(0x2E);
// Send low byte zero to erase
i2c_write(0x00);
// Send high byte zero to erase
i2c_write(0x00);
if (i2c_write(0x6F) == 0) {
// Release bus, end transaction
i2c_stop();
Serial.println("> Data erased.");
}
else {
// Release bus, end transaction
i2c_stop();
Serial.println("> Failed to erase data");
return -1;
}
Serial.print("> Writing data: ");
Serial.print(NewAddr1, HEX);
Serial.print(", ");
Serial.println(NewAddr2, HEX);
for (int a = 0; a != 256; a++) {
// Send start condition and write bit
i2c_start_wait(0 + I2C_WRITE);
// Send command for device to return address
i2c_write(0x2E);
// Send low byte zero to erase
i2c_write(NewAddr1);
// Send high byte zero to erase
i2c_write(NewAddr2);
if (i2c_write(a) == 0) {
// Release bus, end transaction then wait 10ms
i2c_stop();
delay(100);
Serial.print("> Found correct CRC: 0x");
Serial.println(a, HEX);
return a;
}
}
// Release bus, end transaction
i2c_stop();
Serial.println("> Correct CRC not found");
return -1;
}
void ReadAddr(byte Address) {
Serial.println("> Read address");
// Inform the user
Serial.print(" MLX address: ");
Serial.print(Address, HEX);
Serial.print(", Data: ");
// Send start condition and write bit
i2c_start_wait(Address + I2C_WRITE);
// Send command for device to return address
i2c_write(0x2E);
i2c_rep_start(Address + I2C_READ);
// Read 1 byte and then send ack (x2)
Serial.print(i2c_readAck(), HEX);
Serial.print(", ");
Serial.print(i2c_readAck(), HEX);
Serial.print(", ");
Serial.println(i2c_readNak(), HEX);
i2c_stop();
}
float ReadTemp(byte Address) {
int data_low = 0;
int data_high = 0;
int pec = 0;
Serial.println("> Read temperature");
// Inform the user
Serial.print(" MLX address: ");
Serial.print(Address, HEX);
Serial.print(", ");
i2c_start_wait(Address + I2C_WRITE);
// Address of temp bytes
i2c_write(0x07);
// Read - the famous repeat start
i2c_rep_start(Address + I2C_READ);
// Read 1 byte and then send ack (x2)
data_low = i2c_readAck();
data_high = i2c_readAck();
pec = i2c_readNak();
i2c_stop();
// This converts high and low bytes together and processes the temperature
// MSB is a error bit and is ignored for temperatures
// Zero out the data
float temp = 0x0000;
// This masks off the error bit of the high byte, then moves it left
// 8 bits and adds the low byte.
temp = (float)(((data_high & 0x007F) << 8) + data_low);
temp = (temp * 0.02) - 273.16;
Serial.print(temp);
Serial.println(" C");
return temp;
}
Glad to hear I was wrong! However, this is still a Particle forum. You may want to post in the Arduino forum. Have you looked at what Adafruit did in their library?
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