Max31865

Overview

Driver for the Max31865 thermocouple amplifier for use on a Raspberry Pi. Tested with the Raspberry Pi Zero W V 1.2. Should work similarly with other Raspberry PI devices.

For more detail on the Max31865 see the datasheet

Installation

Add to your deps

defp deps do
    [
      ...
      {:max31865, "~> 0.1.0", hex: :max31865},
      ...
    ]
  end

Usage

Start the server, passing in any required config. The will allow for one-shot conversions using Spidev0.0 on a raspberry pi with a PT100 connected with either 2 or 4 wires. For more information on configuration options, please see the Server module.

  def application do
    [
      {Max3186.Server, [rtd_wires: 3, spi_device_cs_pin: 1]}
      extra_applications: [:logger]
    ]
  end

Then you can get the temperature of the probe. A conversion takes ~75ms to complete in one-shot mode. The values returned are in degrees celcius.

iex(1)> Max31865.get_temp()
22.79218286783738