Hobbybotics

2017-01-07T13:20:23-08:00

You haven’t included the link from thermocouple negative to ground, as recommended in the Maxim datasheet.

2017-01-08T12:59:44-08:00

Yep, the link is there. If you look at the schematic you will see a junction from T- to VSS.

	/*
	Demonstration sketch for Hobbybotics MAX6675 Thermocouple breakout board.

	Reads temperature from MAX6675 in celsius and fahrenheit. Prints results to serial monitor.
	*/

	#include <MAX6675.h>

	MAX6675 thermocouple;

	void setup() {
	Serial.begin(9600);
	thermocouple.init(4, 5, 6);

	Serial.println("MAX6675 test");
	// wait for MAX chip to stabilize
	delay(500);
	}

	void loop() {
	// basic readout test, just print the current temp

	Serial.print("C = ");
	Serial.println(float(thermocouple.measure(TEMPC)));
	Serial.print("F = ");
	Serial.println(float(thermocouple.measure(TEMPF)));

	delay(1000);
	}

	/*
	Demonstration sketch for Hobbybotics MAX6675 Thermocouple breakout board.

	Reads temperature from MAX6675 in celsius and fahrenheit. Prints results to I2C LCD.
	*/

	#include <MAX6675.h>
	#include <LCD.h>
	#include <Wire.h>

	MAX6675 thermocouple;

	// Default I2C address for LCD is 0
	LCD lcd(0);

	// make a degree symbol
	uint8_t degree[8] = {140,146,146,140,128,128,128,128};

	void setup() {
	lcd.begin(20, 4);
	lcd.createChar(0, degree);

	thermocouple.init(4, 5, 6);

	// wait for MAX6675 to stabilize
	delay(500);

	lcd.clear();
	lcd.setCursor(0, 0);
	lcd.print("MAX6675 test");
	}

	void loop() {
	float temp_c;
	float temp_f;

	// Read values from the sensor
	temp_c = thermocouple.measure(TEMPC);
	temp_f = thermocouple.measure(TEMPF);

	lcd.setCursor(0,1);
	lcd.print(temp_c);
	lcd.write((byte)0);
	lcd.print("C ");
	lcd.print(temp_f);
	lcd.write((byte)0);
	lcd.print('F');

	delay(1000);
	}

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