MAX6675 K-thermocouple to digital converter

Overview

This is a sample application to read an external MAX6675 cold-junction-compensated K-thermocouple to digital converter.

Requirements

MAX6675 wired to your board SPI bus
K-thermocouple connected to MAX6675 T+/T- inputs

References

MAX6675: https://datasheets.maximintegrated.com/en/ds/MAX6675.pdf

Building and Running

This sample can be built with any board that supports SPI. A sample overlay is provided for the NUCLEO-F030R8 board.

west build -b nucleo_f030r8 samples/sensor/max6675

Sample Output

The application will read and print sensor temperature every second. Note that temperature fetch will fail if the K-thermocouple is not connected. This is because MAX6675 is able to detect if the K-thermocouple is connected or not.

Temperature: 25.25 C
Temperature: 25.50 C

<repeats endlessly every second>