任务总览 

1. 获取SHT40的温湿度数据
2. 搭建HomeAssistant平台
3. 将设备接入到HomeAssistant平台

1.获取SHT40的温湿度数据

先使用官方例程测试一下SHT40传感器

/*************************************************** 
  This is an example for the SHT4x Humidity & Temp Sensor

  Designed specifically to work with the SHT4x sensor from Adafruit
  ----> https://www.adafruit.com/products/4885

  These sensors use I2C to communicate, 2 pins are required to  
  interface
 ****************************************************/
#include <Wire.h>
#include "Adafruit_SHT4x.h"

#define SDA_PIN 27
#define SCL_PIN 26


Adafruit_SHT4x sht4 = Adafruit_SHT4x();

void setup() {
  Serial.begin(115200);

  while (!Serial)
    delay(10);     // will pause Zero, Leonardo, etc until serial console opens

  TwoWire i2cWire = TwoWire(SCL_PIN, SDA_PIN);
  
  Serial.println("Adafruit SHT4x test");
  if (! sht4.begin(&i2cWire)) {
    Serial.println("Couldn't find SHT4x");
    while (1) delay(1);
  }
  Serial.println("Found SHT4x sensor");
  Serial.print("Serial number 0x");
  Serial.println(sht4.readSerial(), HEX);

  // You can have 3 different precisions, higher precision takes longer
  sht4.setPrecision(SHT4X_HIGH_PRECISION);
  switch (sht4.getPrecision()) {
     case SHT4X_HIGH_PRECISION: 
       Serial.println("High precision");
       break;
     case SHT4X_MED_PRECISION: 
       Serial.println("Med precision");
       break;
     case SHT4X_LOW_PRECISION: 
       Serial.println("Low precision");
       break;
  }

  // You can have 6 different heater settings
  // higher heat and longer times uses more power
  // and reads will take longer too!
  sht4.setHeater(SHT4X_NO_HEATER);
  switch (sht4.getHeater()) {
     case SHT4X_NO_HEATER: 
       Serial.println("No heater");
       break;
     case SHT4X_HIGH_HEATER_1S: 
       Serial.println("High heat for 1 second");
       break;
     case SHT4X_HIGH_HEATER_100MS: 
       Serial.println("High heat for 0.1 second");
       break;
     case SHT4X_MED_HEATER_1S: 
       Serial.println("Medium heat for 1 second");
       break;
     case SHT4X_MED_HEATER_100MS: 
       Serial.println("Medium heat for 0.1 second");
       break;
     case SHT4X_LOW_HEATER_1S: 
       Serial.println("Low heat for 1 second");
       break;
     case SHT4X_LOW_HEATER_100MS: 
       Serial.println("Low heat for 0.1 second");
       break;
  }
  
}

void loop() {
  sensors_event_t humidity, temp;
  
  uint32_t timestamp = millis();
  sht4.getEvent(&humidity, &temp);// populate temp and humidity objects with fresh data
  timestamp = millis() - timestamp;

  Serial.print("Temperature: "); Serial.print(temp.temperature); Serial.println(" degrees C");
  Serial.print("Humidity: "); Serial.print(humidity.relative_humidity); Serial.println("% rH");

  Serial.print("Read duration (ms): ");
  Serial.println(timestamp);

  delay(1000);
}

串口打印出来的数据：

Adafruit SHT4x test
Found SHT4x sensor
Serial number 0x10C60BD0
High precision
No heater
Temperature: 30.67 degrees C
Humidity: 70.80% rH
Read duration (ms): 11

2. 搭建HomeAssistant平台

1. SD卡格式化

推荐使用SDFormatter(内存卡修复工具)，经常在Linux和Windwos下使用的SD卡通常会有着不同的分区，在不能操作系统下识别出来的可能都不太一样，因此为了保险起见可以先格式化一下，若没有问题的可以跳过这一步

2. SD卡烧写镜像工具

推荐使用balenaEtcher，这是一个开源的、跨平台的工具，用于将操作系统镜像文件（如 ISO 和 IMG 文件）烧录到 SD 卡和 USB 驱动器中，支持的格式非常的多

1. 选择镜像文件。我是用的是树莓派4，因此选择的是haos_rpi4-64-6.4.img.xz，大家根据自己的设备在附件中选择对应的型号即可。

2. 选择SD卡、U盘等设备

3. Flash！等待烧写完成

3. 上电！配置树莓派

1. 插入烧写好的镜像SD卡到树莓派

2. 接网线到路由器

3. 将电脑通过WiFi或者网线接入到上面树莓派接入的路由器

4. 接HDMI到显示屏等能够显示的设备（有条件的最后接上，没有问题也不是很大）

5. 上电！

若插上HDMI，稍稍稍微的登上那么一段时间，等待系统启动完成就可以看到这个界面了，若没有显示屏，不要捉急，在网站上输入http://homeassistant.local:8123/等待网页显示。若成功启动了，恭喜你完成了第一步！！！

能成功进入网站上，会显示这个界面准备，我一开始信了这个鬼（这最多可能需要20分钟），结果等了一个多小时都没有进去……

第二天起来看到已经到了Home Assistant 的欢迎界面，按照步骤一步步下去就可以了

 

点击FINISH之后，恭喜你现在已经启动并运行了 Home Assistant！！！

HA配置

SSH安装

1. 设置

2. 加载项

3. 加载项商店

4. 搜索ssh

 

5. 安装后

   

6. 成功安装的界面：

Samba 安装

1. 设置

2. 加载项

3. 加载项商店

4. 搜索Samba

5. 安装

   

    

6. 配置：用户名和密码

7. 使用：

   1. Win+R

   2. 输出\ip，例如\\192.168.1.43，这个ip就是上面ssh中查到的ip地址

   3. 就可以跟使用文件夹一样，对树莓派里面的文件进行操作了

安装MQTT

1. 设置

2. 加载项

3. 加载项商店

4. 搜索MQTT

5. 设置-》设备于服务-》打开MQTT-》配置，就可以了以下界面，进行配置ip，用户名、密码等信息，记住这些信息哟

6. 添加设备，使用的软件是MQTTx，发送下面数据，湿度同理

   {
   "name": "SHT40 Humidity",
   "state_topic": "homeassistant/sensor/sht40_humidity/state",
   "unit_of_measurement": "%rH",
   "device_class": "temperature",
   "json_attributes_topic": "homeassistant/sensor/sht40_humidity/attributes",
   "unique_id": "sht40_humidity",
   "device": {
     "identifiers": ["sht40"],
     "name": "SHT40 Sensor",
     "model": "SHT40",
     "manufacturer": "SHT"
   }
   }

   7. 就可以看到添加的设备了

   .

   

#include "Adafruit_SHT4x.h"

#define SDA_PIN 27
#define SCL_PIN 26

Adafruit_SHT4x sht4 = Adafruit_SHT4x();

#include <WiFi.h>
#include <ArduinoMqttClient.h>

char ssid[] = "wifi";  // your network SSID (name)
char pass[] = "passpword";  // your network password 

char mqtt_user[] = "master";
char mqtt_pass[] = "1";

WiFiClient wifiClient;
MqttClient mqttClient(wifiClient);

const char broker[] = "192.168.1.22"; // MQTT broker address
int port = 1883;
const char subscribe_topic[] = "/status";
const char publish_topic_sht40_temperature[] = "homeassistant/sensor/sht40_temperature/state";
const char publish_topic_sht40_humidity[] = "homeassistant/sensor/sht40_humidity/state";

sensors_event_t humidity, temp;

void setup() {

	//打开串口
	Serial.begin(115200);

	while (!Serial)
	  delay(10); // will pause Zero, Leonardo, etc until serial console opens

	//连接WIFI
	// Connect to WiFi
	Serial.print("Attempting to connect to WPA SSID: ");
	Serial.println(ssid);
	while (WiFi.begin(ssid, pass) != WL_CONNECTED) {
	  // failed, retry
	  Serial.print(".");
	  delay(5000);
	}
	Serial.println("\nYou're connected to the network");
	Serial.print("IP Address: ");
	Serial.println(WiFi.localIP());
	Serial.print("Gateway IP: ");
	Serial.println(WiFi.gatewayIP());
	Serial.print("Subnet Mask: ");
	Serial.println(WiFi.subnetMask());
	Serial.print("MAC Address: ");
	//Serial.println(WiFi.macAddress());
	Serial.println();

	//连接MQTT
	// Set MQTT username and password
	mqttClient.setUsernamePassword(mqtt_user, mqtt_pass);

	Serial.print("Attempting to connect to the MQTT broker.");

	if (!mqttClient.connect(broker, port)) {
	  Serial.print("MQTT connection failed! Error code = ");
	  Serial.println(mqttClient.connectError());

	  while (1);
	}

	Serial.println("You're connected to the MQTT broker!");

	Serial.print("Subscribing to topic: ");
	Serial.println(subscribe_topic);

	// Subscribe to a topic
	mqttClient.subscribe(subscribe_topic);

	Serial.print("Waiting for messages on topic: ");
	Serial.println(subscribe_topic);


	//连接SHT40
	TwoWire i2cWire = TwoWire(SCL_PIN, SDA_PIN);

	Serial.println("SHT40 测试");
	if (! sht4.begin(&i2cWire)) {
	  Serial.println("无法访问SHT40");
	  while (1) delay(1);
	}
	Serial.println("开始读取SHT40序列号");
	Serial.print("SHT40的序列号是：");
	Serial.println(sht4.readSerial(), HEX);



	uint32_t timestamp = millis();
	sht4.getEvent(&humidity, &temp);// populate temp and humidity objects with fresh data
	timestamp = millis() - timestamp;

	Serial.print("Temperature: "); Serial.print(temp.temperature); Serial.println(" degrees C");
	Serial.print("Humidity: "); Serial.print(humidity.relative_humidity); Serial.println("% rH");

	Serial.print("Read duration (ms): ");
	Serial.println(timestamp);

	delay(1000);

}

void loop() {
	// put your main code here, to run repeatedly:

	uint32_t timestamp = millis();

	Serial.println("1");

	sht4.getEvent(&humidity, &temp);// populate temp and humidity objects with fresh data

	Serial.println("2");

	timestamp = millis() - timestamp;

	Serial.print("Temperature: "); Serial.print(temp.temperature); Serial.println(" degrees C");
	Serial.print("Humidity: "); Serial.print(humidity.relative_humidity); Serial.println("% rH");

	Serial.print("Read duration (ms): ");
	Serial.println(timestamp);

	delay(1000);

	publishMessage_sht40_temperature(String(temp.temperature));
	publishMessage_sht40_humidity(String(humidity.relative_humidity));

}

// Function to publish a message to the MQTT broker
//发布温度信息
void publishMessage_sht40_temperature(const String &message) {
	mqttClient.beginMessage(publish_topic_sht40_temperature);
	mqttClient.print(message);
	mqttClient.endMessage();
}

// Function to publish a message to the MQTT broker
//发布湿度信息
void publishMessage_sht40_humidity(const String &message) {
	mqttClient.beginMessage(publish_topic_sht40_humidity);
	mqttClient.print(message);
	mqttClient.endMessage();
}