Improve documentation

Author: mnishiguchi

LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2021 Masatoshi Nishiguchi
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1,21 +1,38 @@
 # AHT20
 
-**TODO: Add description**
+[![Hex.pm](https://img.shields.io/hexpm/v/AHT20.svg)](https://hex.pm/packages/AHT20)
+[![API docs](https://img.shields.io/hexpm/v/AHT20.svg?label=docs)](https://hexdocs.pm/AHT20/LcdDisplay.html)
+![CI](https://github.com/mnishiguchi/AHT20/workflows/CI/badge.svg)
 
-## Installation
+Use [AHT20](http://www.aosong.com/en/products-32.html) temperature & humidity sensor in Elixir.
 
-If [available in Hex](https://hex.pm/docs/publish), the package can be installed
-by adding `aht20` to your list of dependencies in `mix.exs`:
+## Usage
+
+Here's an example use:
 
 ```elixir
-def deps do
-  [
-    {:aht20, "~> 0.1.0"}
-  ]
-end
-```
+# Detect I2C devices.
+iex> Circuits.I2C.detect_devices()
+Devices on I2C bus "i2c-1":
+ * 56  (0x38)
+
+1 devices detected on 1 I2C buses
 
-Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
-and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
-be found at [https://hexdocs.pm/aht20](https://hexdocs.pm/aht20).
+# Connect to the sensor.
+iex> {:ok, aht20} = AHT20.start(bus_name: "i2c-1", bus_address: 0x38)
+{:ok, AHT20.Sensor{}}
+
+# Read the humidity and temperature from the sensor.
+iex> AHT20.read_data(aht20)
+{:ok,
+  %AHT20.Measurement{
+  raw_humidity: 158119,
+  raw_temperature: 410343,
+  relative_humidity: 15.079402923583984,
+  temperature_c: 28.26671600341797,
+  temperature_f: 82.88008880615234
+}}
+```
 
+Depending on your hardware configuration, you may need to modify the call to
+`AHT20.start/1`. See `t:AHT20.Sensor.config/0` for parameters.

mix.exs

@@ -1,13 +1,19 @@
 defmodule AHT20.MixProject do
   use Mix.Project
 
+  @version "0.1.0"
+  @source_url "https://github.com/mnishiguchi/aht20"
+
   def project do
     [
       app: :aht20,
-      version: "0.1.0",
+      version: @version,
       elixir: "~> 1.11",
       start_permanent: Mix.env() == :prod,
-      deps: deps()
+      description: "Use AHT20 temperature & humidity sensor in Elixir",
+      deps: deps(),
+      docs: docs(),
+      package: package()
     ]
   end
 
@@ -28,4 +34,30 @@ defmodule AHT20.MixProject do
       {:dialyxir, "~> 1.0", only: [:dev, :test], runtime: false}
     ]
   end
+
+  defp docs do
+    [
+      extras: ["README.md"],
+      main: "readme",
+      source_ref: "v#{@version}",
+      source_url: @source_url
+    ]
+  end
+
+  defp package do
+    %{
+      files: [
+        "lib",
+        "mix.exs",
+        "README.md",
+        "LICENSE*"
+      ],
+      licenses: ["MIT"],
+      links: %{
+        "GitHub" => @source_url,
+        "AHT20 data sheet" =>
+          "https://cdn-learn.adafruit.com/assets/assets/000/091/676/original/AHT20-datasheet-2020-4-16.pdf"
+      }
+    }
+  end
 end