I2C message

I have two slave devices Mini Pro Mini 8MHz 3.3V that have the Adafruit MAX31855(J) thermocouple shields with J Type thermocouples.

The slaves send a message to the Master every 5 seconds:
2,94,0,210 (where =Header / ,=delimiter / 94=actual temp in deg C / 0=fault status / 210 set temp in deg C)

The Master receive code is:

char message[14];

void receiveEvent(int howmany)
{
	int i = 0;
	  while(Wire.available() > 0)
	  {
		  message[i] = Wire.read();
		  i++;
	  }
		Serial.println(message);
		  message[i] = '\0';

}

The Slave send code is:

char msgZone[14];

	  int s1;
	  int s2;
	  int s3;
	  int s4;
	  
	  s1 = numZone;
	  s2 = correctedTemp;
	  s3 = tcError;
	  s4 = setTemp;
	  sprintf(msgZone, "$%d,%d,%d,%d", s1, s2, s3, s4); // size of this string can vary from 10 up to 15
	  Wire.beginTransmission(99); // transmit to device #99 (Master)
	  Wire.write(msgZone);
	  Wire.endTransmission();    // stop transmitting

When I run the Master with the 2 slaves connected I receive the following on the Master Serial Monitor:

$2,98,0,210
$1,26,0,210
$2,99,0,210
$1,26,0,210
$2,100,0,210
$1,26,0,2100
$2,100,0,210
$1,26,0,2100

All is OK and I receive:
$1,26,0,210 (Slave 1 message)
$2,99,0,210 (Slave 2 message)

However, as soon as the temperature from one slave (in this example slave 2) reaches 100 deg C, 3 digits, the message from the other slave (in this example slave 1) is appended with a zero.
$2,100,0,210 THIS IS CORRECT
$1,26,0,2100 THIS IS INCORRECT
this should be:
$1,26,0,210
NOT
$1,26,0,2100

I have changed the char message[14]; to other values but nothing seams to help.

Could someone please point me in the correct direction as to what I am doing wrong?

        Serial.println(message);
          message[i] = '\0';

Those are in the wrong order. You should do the print after storing the null.

Pete

Many thanks - sorted

The slaves send a message to the Master every 5 seconds:

If that is true then it is not a slave. A slave can only respond to a message from a Master. It looks like you have implemented a multi master system.