It's easy to use the MCP9600 thermocouple amplifier with CircuitPython or Python, and the Adafruit CircuitPython MCP9600 module. This module allows you to easily write Python code that reads the temperature from the sensor.
You can use this sensor with any CircuitPython microcontroller board or with a computer that has GPIO and Python thanks to Adafruit_Blinka, our CircuitPython-for-Python compatibility library.
CircuitPython Microcontroller Wiring
First wire up a MCP9600 to your board exactly as shown on the previous pages for Arduino. Here's an example of wiring a Feather M0 to the sensor with I2C:
Python Computer Wiring
Since there's dozens of Linux computers/boards you can use we will show wiring for Raspberry Pi. For other platforms, please visit the guide for CircuitPython on Linux to see whether your platform is supported.
Here's the Raspberry Pi wired with I2C:
CircuitPython Installation of MCP9600 Library
Next you'll need to install the Adafruit CircuitPython MCP9600 library on your CircuitPython board.
First make sure you are running the latest version of Adafruit CircuitPython for your board.
Next you'll need to install the necessary libraries to use the hardware--carefully follow the steps to find and install these libraries from Adafruit's CircuitPython library bundle. Our introduction guide has a great page on how to install the library bundle for both express and non-express boards.
Copy the following files from the library bundle to your CIRCUITPY drive:
- adafruit_mcp9600.mpy
- adafruit_bus_device
Before continuing make sure your board's lib folder or root filesystem has the adafruit_mcp9600.mpy, and adafruit_bus_device files and folders copied over.
Next connect to the board's serial REPL so you are at the CircuitPython >>> prompt.
Python Installation of MCP9600 Library
You'll need to install the Adafruit_Blinka library that provides the CircuitPython support in Python. This may also require enabling I2C on your platform and verifying you are running Python 3. Since each platform is a little different, and Linux changes often, please visit the CircuitPython on Linux guide to get your computer ready!
Once that's done, from your command line run the following command:
pip3 install adafruit-circuitpython-mcp9600
If your default Python is version 3 you may need to run 'pip' instead. Just make sure you aren't trying to use CircuitPython on Python 2.x, it isn't supported!
CircuitPython and Python Usage
To demonstrate the usage of the sensor we'll initialize it and read the temperature from the board's Python REPL.
Run the following code to import the necessary modules and initialize the I2C connection with the sensor. Note that frequency must be set when I2C is initialised for the MCP9600 to work:
import board import busio import adafruit_mcp9600 i2c = busio.I2C(board.SCL, board.SDA, frequency=100000) mcp = adafruit_mcp9600.MCP9600(i2c)
Now you're ready to read values from the sensor using any of these properties:
- temperature - The thermocouple or hot junction temperature in degrees Celsius.
- ambient_temperature - The ambient or cold-junction temperature in degrees Celsius.
- delta_temperature - The difference between the thermocouple (hot junction) and ambient (cold junction) temperatures in degrees Celsius.
print(mcp.temperature)
# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
# SPDX-License-Identifier: MIT
import time
import board
import busio
import adafruit_mcp9600
i2c = busio.I2C(board.SCL, board.SDA, frequency=100000)
mcp = adafruit_mcp9600.MCP9600(i2c)
while True:
print((mcp.ambient_temperature, mcp.temperature, mcp.delta_temperature))
time.sleep(1)
Alerts and More
The MCP9600 breakout allows you to configure four separate alerts on four pins. Connect the alert pins to digital output pins on your board or computer, and use the alert configuration in the MCP9600 library to configure them. Check out the documentation for more information!
