Full Code of Hypfer/esp8266-midea-dehumidifier for AI

Repository: Hypfer/esp8266-midea-dehumidifier
Branch: master
Commit: 317e2295dde7
Files: 8
Total size: 39.1 KB

Directory structure:
gitextract_o0uhkbxp/

├── LICENSE
├── README.md
└── src/
    └── esp8266-midea-dehumidifier/
        ├── checksums.ino
        ├── configFileHandling.ino
        ├── esp8266-midea-dehumidifier.ino
        ├── serialCommunication.ino
        ├── types.h
        └── wifi.h

================================================
FILE CONTENTS
================================================

================================================
FILE: LICENSE
================================================
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================================================
FILE: README.md
================================================
<div align="center">
    <img src="https://github.com/Hypfer/esp8266-midea-dehumidifier/blob/master/img/logo.svg" width="800" alt="esp8266-midea-dehumidifier">
    <p align="center"><h2>Free your dehumidifier from the cloud</h2></p>
</div>

This repo contains software to build a replacement wifi adapter for your wifi-enabled midea dehumidifier
which enables cloud-free operation utilizing MQTT.

Home Assistant Autodiscovery for all features is supported since Home Assistant 2021.08.
Furthermore, the WifiManager library is used for on-the-fly configuration.
Also, ArduinoOTA is used, so that firmware updates are possible even with a reassembled device.


If you're looking for the exact opposite of this, check out [esp8266-deerma-humidifier](https://github.com/Hypfer/esp8266-deerma-humidifier/).
Or maybe even use both simultaneously and see who wins?


This should work with all wifi-enabled Midea-made dehumidifiers. They are sold under different brands including:
* Comfee
* Inventor

Quoting from [node-mideahvac](https://github.com/reneklootwijk/node-mideahvac):

The WiFi interface [on these machines] is provided by a dongle, called WiFi SmartKey, either connected to an USB type-A
connector or a JST-HX type of connector. This dongle wraps the UART protocol used to communicate with the unit with a
layer for authentication and encryption for communication with a mobile app via the Midea cloud or directly via a local LAN connection.

However, it turned out the dongle is just connected to a serial interface (TTL level) of the unit.
This means an alternative is to hook up directly to this serial interface and bypass the cloud, authentication and encryption stuff,
[which is exactly what this project does].

## Compatibility list
This list contains all tested and known-working dehumidifiers:

* Midea MAD22S1WWT
* Comfee MDDF-16DEN7-WF
* Comfee MDDF-20DEN7-WF
* Inventor Eva II PRO WI-FI
* Inventor EVA ION PRO WiFi 20L
* Midea Cube 20 ([#22](https://github.com/Hypfer/esp8266-midea-dehumidifier/issues/22))
* Midea Cube 35 ([#29](https://github.com/Hypfer/esp8266-midea-dehumidifier/issues/29))
* Midea Cube 50 ([#27](https://github.com/Hypfer/esp8266-midea-dehumidifier/issues/27))

Additionally, there are models that technically also work but have some issues:

* Comfee MDDF-20DEN7 - lacks Wi-Fi Button and USB port. The guide below doesn't fully apply! ([#24](https://github.com/Hypfer/esp8266-midea-dehumidifier/pull/24))

## Health and Safety
Please note that some of the supported dehumidifiers such as the Comfee MDDF-20DEN7-WF use R290 as its coolant which - [while having a much lower global warming potential than other coolants](https://en.wikipedia.org/wiki/Refrigerant#Environmental_issues) -
is also **Propane**.

Yes, _the_ **Propane**.

Therefore, when disassembling, please be extra careful so that you don't damage anything since a leak may result in
you blowing yourself up and/or burning your house down.

## Building the Adapter
![adapter](./img/adapter.jpg)
This is how the finished replacement adapter I'm using looks like.

To build one of these, you will need:

* ESP8266 ESP-01 Module
* ESP-01 Serial Adapter Board with 3.3v to 5v Level Shifters
* USB A to Terminal Plug Adapter
* Some Dupont Cables
* Something to flash the ESP-01

Just source those from the supplier of your choice and compare product listings with this finished adapter photo.

For flashing the ESP-01, there are some nice and self-contained USB to ESP-01 Adapters.

However, they cannot flash the module without soldering an extra button to it.
You might want to get one of those as well and then follow [this instructable](https://www.instructables.com/id/USB-to-ESP-01-Board-Adapter-Modification/).

The firmware can be built and flashed using the Arduino IDE.

For this, you will need to add ESP8266 support to it by [using the Boards Manager](https://github.com/esp8266/Arduino#installing-with-boards-manager).

Furthermore, you will also need to install the following libraries using the Library Manager:

* ArduinoOTA 1.0.3
* ArduinoJSON 6.10.1
* PubSubClient 2.8.0
* WiFiManager 0.15.0

## Using the Adapter
Current supported features are:

* On/Off
* Mode
* Fan Speed
* Humidity Setpoint

Also, the WiFi indicator on the unit continues to work like it's the real wifi adapter.

### Configuring Wifi
Since this project is using the WifiManager library, the ESP8266 will open up a WiFi Access Point for its initial configuration
or if it is unable to connect to the previously configured WiFi.

The library pretends that said WiFi AP requires a captive portal which triggers a notification on recent android phones.
Simply connect to the AP with your phone, tap the "Login required"-notification and you should be able to configure everything.

If for any reason you require to reconfigure everything, you can simply push and the WiFi button of your Dehumidifier for three seconds.
This also deletes the config and opens up the initial configuration Access Point again.

### Controlling the Appliance
Since we're using the Home Assistant Autodiscovery feature, everything should just work™.

If you're using something else other than Home Assistant, you can of course also control it by manually sending
JSONs to the command mqtt topic of the unit:
```
esp8266-midea-dehumidifier/DEHUMIDIFIER-FFFFFF/command

{
	"state": "on",
	"humiditySetpoint": 55,
	"fanSpeed": "medium",
	"mode": "setpoint"
}
```
You can omit parameters that you don't want to change.

The current status of the unit will be published like this:
```
esp8266-midea-dehumidifier/DEHUMIDIFIER-FFFFFF/state

{
	"state": "on",
	"humiditySetpoint": 55,
	"humidityCurrent": 41,
	"errorCode": 0,
	"fanSpeed": "medium",
	"mode": "setpoint"
}
```

## Misc
As you can see, on the Comfee MDDF-20DEN7-WF, the replacement adapter actually fits inside the mounting point of the regular WiFi adapter.
![comfee adapter](./img/comfee_adapter_mounted.jpg)

## References and sources

The knowledge to create the logic to monitor and control the Midea-'like' AC units was gathered by reverse engineering Android applications from various vendors, analyzing the UART protocol between an Artel unit and an SK103 SmartKey, documents found on the Internet, primarily in Chinese and the work from:

* Mac Zhou: <https://github.com/mac-zhou/midea-msmart>
* NeoAcheron: <https://github.com/NeoAcheron/midea-ac-py>
* Rene Klootwijk: <https://github.com/reneklootwijk/node-mideahvac>


================================================
FILE: src/esp8266-midea-dehumidifier/checksums.ino
================================================
static const byte crc_table[] = {  
    0x00,0x5e,0xbc,0xE2,0x61,0x3F,0xDD,0x83,
    0xC2,0x9C,0x7E,0x20,0xA3,0xFD,0x1F,0x41,
    0x9D,0xC3,0x21,0x7F,0xFC,0xA2,0x40,0x1E,
    0x5F,0x01,0xE3,0xBD,0x3E,0x60,0x82,0xDC,
    0x23,0x7D,0x9F,0xC1,0x42,0x1C,0xFE,0xA0,
    0xE1,0xBF,0x5D,0x03,0x80,0xDE,0x3C,0x62,
    0xBE,0xE0,0x02,0x5C,0xDF,0x81,0x63,0x3D,
    0x7C,0x22,0xC0,0x9E,0x1D,0x43,0xA1,0xFF,
    0x46,0x18,0xFA,0xA4,0x27,0x79,0x9B,0xC5,
    0x84,0xDA,0x38,0x66,0xE5,0xBB,0x59,0x07,
    0xDB,0x85,0x67,0x39,0xBA,0xE4,0x06,0x58,
    0x19,0x47,0xA5,0xFB,0x78,0x26,0xC4,0x9A,
    0x65,0x3B,0xD9,0x87,0x04,0x5A,0xB8,0xE6,
    0xA7,0xF9,0x1B,0x45,0xC6,0x98,0x7A,0x24,
    0xF8,0xA6,0x44,0x1A,0x99,0xC7,0x25,0x7B,
    0x3A,0x64,0x86,0xD8,0x5B,0x05,0xE7,0xB9,
    0x8C,0xD2,0x30,0x6E,0xED,0xB3,0x51,0x0F,
    0x4E,0x10,0xF2,0xAC,0x2F,0x71,0x93,0xCD,
    0x11,0x4F,0xAD,0xF3,0x70,0x2E,0xCC,0x92,
    0xD3,0x8D,0x6F,0x31,0xB2,0xEC,0x0E,0x50,
    0xAF,0xF1,0x13,0x4D,0xCE,0x90,0x72,0x2C,
    0x6D,0x33,0xD1,0x8F,0x0C,0x52,0xB0,0xEE,
    0x32,0x6C,0x8E,0xD0,0x53,0x0D,0xEF,0xB1,
    0xF0,0xAE,0x4C,0x12,0x91,0xCF,0x2D,0x73,
    0xCA,0x94,0x76,0x28,0xAB,0xF5,0x17,0x49,
    0x08,0x56,0xB4,0xEA,0x69,0x37,0xD5,0x8B,
    0x57,0x09,0xEB,0xB5,0x36,0x68,0x8A,0xD4,
    0x95,0xCB,0x29,0x77,0xF4,0xAA,0x48,0x16,
    0xE9,0xB7,0x55,0x0B,0x88,0xD6,0x34,0x6A,
    0x2B,0x75,0x97,0xC9,0x4A,0x14,0xF6,0xA8,
    0x74,0x2A,0xC8,0x96,0x15,0x4B,0xA9,0xF7,
    0xB6,0xE8,0x0A,0x54,0xD7,0x89,0x6B,0x35
};

byte crc8(byte *addr, byte len){
  byte crc = 0;
  while(len--){
     crc = crc_table[*addr++ ^ crc]; 
  }
 return crc;
}

byte checksum(byte *addr, byte len) {
  byte sum = 0;
  *addr++;

  while(len--) {
    sum = sum + *addr++;
  }

  return 256 - sum;
}


================================================
FILE: src/esp8266-midea-dehumidifier/configFileHandling.ino
================================================
void saveConfig() {
  DynamicJsonDocument json(512);
  json["mqtt_server"] = mqtt_server;
  json["username"] = username;
  json["password"] = password;

  File configFile = SPIFFS.open("/config.json", "w");
  if (!configFile) {
    return;
  }

  serializeJson(json, configFile);
  configFile.close();
}

void loadConfig() {
  if (SPIFFS.begin()) {

    if (SPIFFS.exists("/config.json")) {
      File configFile = SPIFFS.open("/config.json", "r");

      if (configFile) {
        const size_t size = configFile.size();
        std::unique_ptr<char[]> buf(new char[size]);

        configFile.readBytes(buf.get(), size);
        DynamicJsonDocument json(512);

        if (DeserializationError::Ok == deserializeJson(json, buf.get())) {
          strcpy(mqtt_server, json["mqtt_server"]);
          strcpy(username, json["username"]);
          strcpy(password, json["password"]);
        }
      }
    }
  }
}


================================================
FILE: src/esp8266-midea-dehumidifier/esp8266-midea-dehumidifier.ino
================================================
#include "types.h"
#include "wifi.h"

#include <ESP8266WiFi.h>
#include <DNSServer.h>
#include <ESP8266WebServer.h>
#include <ArduinoJson.h>
#include <WiFiManager.h>
#include <PubSubClient.h>
//#include <SoftwareSerial.h>
#include <ArduinoOTA.h>
#include <FS.h>

dehumidifierState_t state;

byte serialRxBuf[255];
byte serialTxBuf[255];
uint8_t mqttRetryCounter = 0;


WiFiManager wifiManager;
WiFiClient wifiClient;
PubSubClient mqttClient;

WiFiManagerParameter custom_mqtt_server("server", "mqtt server", mqtt_server, sizeof(mqtt_server));
WiFiManagerParameter custom_mqtt_user("user", "MQTT username", username, sizeof(username));
WiFiManagerParameter custom_mqtt_pass("pass", "MQTT password", password, sizeof(password));

unsigned long lastMqttConnectionAttempt = millis();
const long mqttConnectionInterval = 60000;

unsigned long statusPollPreviousMillis = millis();
const long statusPollInterval = 30000;

char identifier[24];
#define FIRMWARE_PREFIX "esp8266-midea-dehumidifier"
#define AVAILABILITY_ONLINE "online"
#define AVAILABILITY_OFFLINE "offline"
char MQTT_TOPIC_AVAILABILITY[128];
char MQTT_TOPIC_STATE[128];
char MQTT_TOPIC_COMMAND[128];

char MQTT_TOPIC_AUTOCONF_WIFI_SENSOR[128];
char MQTT_TOPIC_AUTOCONF_HUMIDITY_SENSOR[128];


char MQTT_TOPIC_AUTOCONF_FAN[128];
char MQTT_TOPIC_AUTOCONF_HUMIDIFIER[128];




bool shouldSaveConfig = false;

void saveConfigCallback () {
  shouldSaveConfig = true;
}

void setup() {
  Serial.begin(9600);

  //Initializing with defaults until we have a status update
  state.powerOn = false;
  state.fanSpeed = low;
  state.mode = setpoint;
  state.humiditySetpoint = 55;
  state.currentHumidity = 45;
  state.errorCode = 0;

  delay(3000);
  updateAndSendNetworkStatus(false);


  snprintf(identifier, sizeof(identifier), "DEHUMIDIFIER-%X", ESP.getChipId());
  snprintf(MQTT_TOPIC_AVAILABILITY, 127, "%s/%s/status", FIRMWARE_PREFIX, identifier);
  snprintf(MQTT_TOPIC_STATE, 127, "%s/%s/state", FIRMWARE_PREFIX, identifier);
  snprintf(MQTT_TOPIC_COMMAND, 127, "%s/%s/command", FIRMWARE_PREFIX, identifier);

  snprintf(MQTT_TOPIC_AUTOCONF_HUMIDITY_SENSOR, 127, "homeassistant/sensor/%s/%s_humidity/config", FIRMWARE_PREFIX, identifier);
  snprintf(MQTT_TOPIC_AUTOCONF_WIFI_SENSOR, 127, "homeassistant/sensor/%s/%s_wifi/config", FIRMWARE_PREFIX, identifier);

  snprintf(MQTT_TOPIC_AUTOCONF_FAN, 127, "homeassistant/select/%s/%s_fan/config", FIRMWARE_PREFIX, identifier);
  snprintf(MQTT_TOPIC_AUTOCONF_HUMIDIFIER, 127, "homeassistant/humidifier/%s/%s_dehumidifier/config", FIRMWARE_PREFIX, identifier);


  WiFi.hostname(identifier);

  loadConfig();

  setupWifi();
  setupOTA();
  mqttClient.setServer(mqtt_server, 1883);
  mqttClient.setKeepAlive(10);
  mqttClient.setBufferSize(2048);
  mqttClient.setCallback(mqttCallback);

  mqttReconnect();
}

void setupOTA() {

  ArduinoOTA.onStart([]() {
    //Serial.println("Start");
  });
  ArduinoOTA.onEnd([]() {
    //Serial.println("\nEnd");
  });
  ArduinoOTA.onProgress([](unsigned int progress, unsigned int total) {
    //Serial.printf("Progress: %u%%\r", (progress / (total / 100)));
  });
  ArduinoOTA.onError([](ota_error_t error) {
    /*
      Serial.printf("Error[%u]: ", error);
      if (error == OTA_AUTH_ERROR) Serial.println("Auth Failed");
      else if (error == OTA_BEGIN_ERROR) Serial.println("Begin Failed");
      else if (error == OTA_CONNECT_ERROR) Serial.println("Connect Failed");
      else if (error == OTA_RECEIVE_ERROR) Serial.println("Receive Failed");
      else if (error == OTA_END_ERROR) Serial.println("End Failed");
    */
  });

  ArduinoOTA.setHostname(identifier);

  //This is less of a security measure and more a accidential flash prevention
  ArduinoOTA.setPassword(identifier);
  ArduinoOTA.begin();
}


void loop() {
  ArduinoOTA.handle();
  handleUart();
  mqttClient.loop();

  if (statusPollInterval <= (millis() - statusPollPreviousMillis)) {
    statusPollPreviousMillis = millis();
    getStatus();
  }

  if (!mqttClient.connected() && (mqttConnectionInterval <= (millis() - lastMqttConnectionAttempt)) )  {
    lastMqttConnectionAttempt = millis();
    mqttReconnect();
  }
}

void setupWifi() {
  wifiManager.setDebugOutput(false);
  wifiManager.setSaveConfigCallback(saveConfigCallback);

  wifiManager.addParameter(&custom_mqtt_server);
  wifiManager.addParameter(&custom_mqtt_user);
  wifiManager.addParameter(&custom_mqtt_pass);

  WiFi.hostname(identifier);
  wifiManager.autoConnect(identifier);
  mqttClient.setClient(wifiClient);

  strcpy(mqtt_server, custom_mqtt_server.getValue());
  strcpy(username, custom_mqtt_user.getValue());
  strcpy(password, custom_mqtt_pass.getValue());

  if (shouldSaveConfig) {
    saveConfig();
  } else {
    //For some reason, the read values get overwritten in this function
    //To combat this, we just reload the config
    //This is most likely a logic error which could be fixed otherwise
    loadConfig();
  }
}

void resetWifiSettingsAndReboot() {
  wifiManager.resetSettings();
  updateAndSendNetworkStatus(false);
  delay(3000);
  ESP.restart();
}

void mqttReconnect()
{
  for (int attempt = 0; attempt < 3; ++attempt) {
    if (mqttClient.connect(identifier, username, password, MQTT_TOPIC_AVAILABILITY, 1, true, AVAILABILITY_OFFLINE)) {
      mqttClient.publish(MQTT_TOPIC_AVAILABILITY, AVAILABILITY_ONLINE, true);
      updateAndSendNetworkStatus(true);
      getStatus();
      publishAutoConfig();

      //Make sure to subscribe after polling the status so that we never execute commands with the default data
      mqttClient.subscribe(MQTT_TOPIC_COMMAND);
      break;
    } else {
      delay(5000);
    }
  }
}

boolean isMqttConnected() {
  return mqttClient.connected();
}

void publishState() {
  DynamicJsonDocument wifiJson(192);
  DynamicJsonDocument stateJson(604);
  char payload[256];

  wifiJson["ssid"] = WiFi.SSID();
  wifiJson["ip"] = WiFi.localIP().toString();
  wifiJson["rssi"] = WiFi.RSSI();

  stateJson["state"] = state.powerOn ? "on" : "off";
  stateJson["humiditySetpoint"] = state.humiditySetpoint;
  stateJson["humidityCurrent"] = state.currentHumidity;
  stateJson["errorCode"] = state.errorCode;

  switch (state.fanSpeed) {
    case low:
      stateJson["fanSpeed"] = "low";
      break;
    case medium:
      stateJson["fanSpeed"] = "medium";
      break;
    case high:
      stateJson["fanSpeed"] = "high";
      break;
  }

  switch (state.mode) {
    case setpoint:
      stateJson["mode"] = "setpoint";
      break;
    case continuous:
      stateJson["mode"] = "continuous";
      break;
    case smart:
      stateJson["mode"] = "smart";
      break;
    case clothesDrying:
      stateJson["mode"] = "clothesDrying";
      break;
  }

  stateJson["wifi"] = wifiJson.as<JsonObject>();

  serializeJson(stateJson, payload);
  mqttClient.publish(MQTT_TOPIC_STATE, payload, true);
}

void mqttCallback(char* topic, byte* payload, unsigned int length) {
  if (strcmp(topic, MQTT_TOPIC_COMMAND) == 0) {
    DynamicJsonDocument commandJson(256);
    char payloadText[length + 1];

    snprintf(payloadText, length + 1, "%s", payload);

    DeserializationError err = deserializeJson(commandJson, payloadText);

    if (!err) {
      handleStateUpdateRequest(
        commandJson["state"].as<String>(),
        commandJson["mode"].as<String>(),
        commandJson["fanSpeed"].as<String>(),
        commandJson["humiditySetpoint"].as<byte>()
      );

      getStatus();
    }
  }
}

void publishAutoConfig() {
  char mqttPayload[2048];
  DynamicJsonDocument device(256);
  DynamicJsonDocument autoconfPayload(1024);
  StaticJsonDocument<64> identifiersDoc;
  JsonArray identifiers = identifiersDoc.to<JsonArray>();

  identifiers.add(identifier);

  device["identifiers"] = identifiers;
  device["manufacturer"] = "Midea Group Co., Ltd.";
  device["model"] = "Generic Dehumidifier";
  device["name"] = identifier;
  device["sw_version"] = "2023.08.0";


  autoconfPayload["device"] = device.as<JsonObject>();
  autoconfPayload["availability_topic"] = MQTT_TOPIC_AVAILABILITY;
  autoconfPayload["state_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["name"] = "WiFi";
  autoconfPayload["value_template"] = "{{value_json.wifi.rssi}}";
  autoconfPayload["unique_id"] = identifier + String("_wifi");
  autoconfPayload["unit_of_measurement"] = "dBm";
  autoconfPayload["json_attributes_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["json_attributes_template"] = "{\"ssid\": \"{{value_json.wifi.ssid}}\", \"ip\": \"{{value_json.wifi.ip}}\"}";
  autoconfPayload["icon"] = "mdi:wifi";

  serializeJson(autoconfPayload, mqttPayload);
  mqttClient.publish(MQTT_TOPIC_AUTOCONF_WIFI_SENSOR, mqttPayload, true);

  autoconfPayload.clear();


  autoconfPayload["device"] = device.as<JsonObject>();
  autoconfPayload["availability_topic"] = MQTT_TOPIC_AVAILABILITY;
  autoconfPayload["state_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["name"] = "Humidity";
  autoconfPayload["device_class"] = "humidity";
  autoconfPayload["unit_of_measurement"] = "%";
  autoconfPayload["value_template"] = "{{value_json.humidityCurrent}}";
  autoconfPayload["unique_id"] = identifier + String("_humidity");

  serializeJson(autoconfPayload, mqttPayload);
  mqttClient.publish(MQTT_TOPIC_AUTOCONF_HUMIDITY_SENSOR, mqttPayload, true);

  autoconfPayload.clear();


  StaticJsonDocument<64> optionsDoc;
  JsonArray speedOptions = optionsDoc.to<JsonArray>();

  speedOptions.add("low");
  speedOptions.add("medium");
  speedOptions.add("high");

  autoconfPayload["device"] = device.as<JsonObject>();
  autoconfPayload["availability_topic"] = MQTT_TOPIC_AVAILABILITY;
  autoconfPayload["name"] = "Fan";
  autoconfPayload["unique_id"] = identifier + String("_fan");
  autoconfPayload["icon"] = "mdi:fan";

  autoconfPayload["state_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["command_topic"] = MQTT_TOPIC_COMMAND;

  autoconfPayload["options"] = speedOptions;
  autoconfPayload["state_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["command_topic"] = MQTT_TOPIC_COMMAND;
  autoconfPayload["value_template"] = "{{value_json.fanSpeed}}";
  autoconfPayload["command_template"] = "{\"fanSpeed\": \"{{value}}\"}";

  serializeJson(autoconfPayload, mqttPayload);
  mqttClient.publish(MQTT_TOPIC_AUTOCONF_FAN, mqttPayload, true);

  autoconfPayload.clear();


  autoconfPayload["device"] = device.as<JsonObject>();
  autoconfPayload["availability_topic"] = MQTT_TOPIC_AVAILABILITY;
  autoconfPayload["name"] = "Dehumidifier";
  autoconfPayload["unique_id"] = identifier + String("_dehumidifier");
  autoconfPayload["device_class"] = "dehumidifier";

  autoconfPayload["max_humidity"] = 85;
  autoconfPayload["min_humidity"] = 35;

  autoconfPayload["state_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["state_value_template"] = "{\"state\": \"{{value_json.state}}\"}";
  autoconfPayload["payload_on"] = "{\"state\": \"on\"}";
  autoconfPayload["payload_off"] = "{\"state\": \"off\"}";
  autoconfPayload["command_topic"] = MQTT_TOPIC_COMMAND;
  autoconfPayload["state_value_template"] = "{\"state\": \"{{value_json.state}}\"}";
  autoconfPayload["payload_on"] = "{\"state\": \"on\"}";
  autoconfPayload["payload_off"] = "{\"state\": \"off\"}";

  StaticJsonDocument<64> modesDoc;
  JsonArray modes = modesDoc.to<JsonArray>();

  autoconfPayload["target_humidity_state_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["target_humidity_command_topic"] = MQTT_TOPIC_COMMAND;
  autoconfPayload["target_humidity_state_template"] = "{{value_json.humiditySetpoint | int}}";
  autoconfPayload["target_humidity_command_template"] = "{\"humiditySetpoint\": {{value | int}}}";

  modes.add("setpoint");
  modes.add("continuous");
  modes.add("smart");
  modes.add("clothesDrying");

  autoconfPayload["modes"] = modes;
  autoconfPayload["mode_state_topic"] = MQTT_TOPIC_STATE;
  autoconfPayload["mode_command_topic"] = MQTT_TOPIC_COMMAND;
  autoconfPayload["mode_state_template"] = "{{value_json.mode}}";
  autoconfPayload["mode_command_template"] = "{\"mode\": \"{{value}}\"}";

  serializeJson(autoconfPayload, mqttPayload);
  mqttClient.publish(MQTT_TOPIC_AUTOCONF_HUMIDIFIER, mqttPayload, true);

  autoconfPayload.clear();
}


================================================
FILE: src/esp8266-midea-dehumidifier/serialCommunication.ino
================================================
byte networkStatus[20];
byte currentHeader[10];
byte getStatusCommand[21] = {
  0x41, 0x81, 0x00, 0xff, 0x03, 0xff,
  0x00, 0x02, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
  0x00, 0x00, 0x03
};
byte setStatusCommand[25];

void parseState() {
  state.powerOn = serialRxBuf[11] & 0x01 > 0;
  state.mode = (dehumMode_t)(serialRxBuf[12] & 0x0f);
  state.fanSpeed = (fanSpeed_t)(serialRxBuf[13] & 0x7f);

  state.humiditySetpoint = serialRxBuf[17] >= 100 ? 99 : serialRxBuf[17];
  state.currentHumidity = serialRxBuf[26];
  state.errorCode = serialRxBuf[31];

  clearRxBuf();
}

void clearRxBuf() {
  //Clear everything for the next message
  memset(serialRxBuf, 0, sizeof(serialRxBuf));
}
void clearTxBuf() {
  //Clear everything for the next message
  memset(serialTxBuf, 0, sizeof(serialTxBuf));
}

void handleUart() {
  if (Serial.available()) {
    Serial.readBytesUntil('\n', serialRxBuf, 250);
    if (serialRxBuf[10] == 0xc8) {
      parseState();
      publishState();
    } else if (serialRxBuf[10] == 0x63) {
      updateAndSendNetworkStatus(isMqttConnected());
    } else if ( //Yes, this is ugly :(
      serialRxBuf[10] == 0x0 &&
      serialRxBuf[50] == 0xaa &&
      serialRxBuf[51] == 0x1e &&
      serialRxBuf[52] == 0xa1 && //Appliance Type
      serialRxBuf[58] == 0x03 &&
      serialRxBuf[59] == 0x64 &&
      serialRxBuf[61] == 0x01 &&
      serialRxBuf[65] == 0x01
    ) {
      resetWifiSettingsAndReboot();
    } else {
      //Serial.print("Received msg with invalid type: ");
      //Serial.println(serialRxBuf[10]);
    }
  }
}

void writeHeader(byte msgType, byte agreementVersion, byte packetLength) {
  currentHeader[0] = 0xAA; //Sync Header
  currentHeader[1] = 10 + packetLength + 1;
  currentHeader[2] = 0xA1; //ApplianceType
  currentHeader[3] = 0x00; //Frame sync check (not used)
  currentHeader[4] = 0x00; //Reserved
  currentHeader[5] = 0x00; //Reserved
  currentHeader[6] = 0x00; //MsgId
  currentHeader[7] = 0x00; //ProtocolVersion
  currentHeader[8] = agreementVersion;
  currentHeader[9] = msgType;
}

void handleStateUpdateRequest(String requestedState, String mode, String fanSpeed, byte humiditySetpoint) {
  dehumidifierState_t newState;

  newState.powerOn = state.powerOn;
  newState.mode = state.mode;
  newState.fanSpeed = state.fanSpeed;
  newState.humiditySetpoint = state.humiditySetpoint;

  if (requestedState == "on") {
    newState.powerOn = true;
  } else if (requestedState == "off") {
    newState.powerOn = false;
  }

  if (mode == "setpoint") {
    newState.mode = (dehumMode_t)setpoint;
  } else if (mode == "continuous") {
    newState.mode = (dehumMode_t)continuous;
  } else if (mode == "smart") {
    newState.mode = (dehumMode_t)smart;
  } else if (mode == "clothesDrying") {
    newState.mode = (dehumMode_t)clothesDrying;
  }

  if (fanSpeed == "low") {
    newState.fanSpeed = (fanSpeed_t)low;
  } else if (fanSpeed == "medium") {
    newState.fanSpeed = (fanSpeed_t)medium;
  } else if (fanSpeed == "high") {
    newState.fanSpeed = (fanSpeed_t)high;
  }

  if (humiditySetpoint && humiditySetpoint >= 35 && humiditySetpoint <= 85) {
    newState.humiditySetpoint = humiditySetpoint;
  }

  if ( //Only send if we have updates
    newState.powerOn != state.powerOn ||
    newState.mode != state.mode ||
    newState.fanSpeed != state.fanSpeed ||
    newState.humiditySetpoint != state.humiditySetpoint
  ) {
    updateSetStatus(
      newState.powerOn,
      newState.mode,
      newState.fanSpeed,
      newState.humiditySetpoint
    );
    sendSetStatus();

    //Write back so that we don't swallow commands if there are many coming right after each other
    //This may cause unexpected results if the connection to the unit doesn't work
    state.powerOn = newState.powerOn;
    state.mode = newState.mode;
    state.fanSpeed = newState.fanSpeed;
    state.humiditySetpoint = newState.humiditySetpoint;
    delay(30);
  }
}

void sendSetStatus() {
  sendMessage(0x02, 0x03, 25, setStatusCommand);
}

void updateSetStatus(boolean powerOn, dehumMode_t dehumMode, fanSpeed_t fanSpeed, byte humiditySetpoint) {
  memset(setStatusCommand, 0, sizeof(setStatusCommand));

  setStatusCommand[0] = 0x48; //Magic
  setStatusCommand[1] = powerOn ? 0x01 : 0x00;
  setStatusCommand[2] = (byte)(dehumMode & 0x0f);
  setStatusCommand[3] = (byte)fanSpeed;
  setStatusCommand[7] = humiditySetpoint;
}

void updateAndSendNetworkStatus(boolean isConnected) {
  updateNetworkStatus(isConnected);
  sendMessage(0x0D, 0x03, 20, networkStatus);
}

void getStatus() {
  sendMessage(0x03, 0x03, 21, getStatusCommand);
}

void updateNetworkStatus(boolean isConnected) {
  memset(networkStatus, 0, sizeof(networkStatus));

  // Byte 0: Module type:
  // - 0x00 RF module
  // - 0x01 WiFi module
  networkStatus[0] = 0x01;

  // Byte 1: WiFi module working mode:
  // - 0x01 Client mode
  // - 0x02 Configuration mode
  // - 0x03 AP mode
  networkStatus[1] = 0x01;

  // Byte 2: WiFi signal strength
  // - 0x00 No signal
  // - 0x01 Weak
  // - 0x02 Low
  // - 0x03 Medium
  // - 0x04 Strong
  // - 0xFF WiFi is not supported
  networkStatus[2] = 0x04;

  // Byte 3-6: IPv4 address of client in reverse order
  networkStatus[3] = 1;
  networkStatus[4] = 0;
  networkStatus[5] = 0;
  networkStatus[6] = 127;

  // Byte 7: RF Signal strength
  // - 0x00, no signal
  // - 0x01, weak
  // - 0x02, low
  // - 0x03, medium
  // - 0x04, strong
  // - 0xFF, RF is not supported
  networkStatus[7] = 0xff;

  // Byte 8: Router status
  // - 0x00, wireless router is connected
  // - 0x01, wireless router not connected
  // - 0x02, connecting to a wireless router
  // - 0x03, password verification error
  // - 0x04, no wireless router found
  // - 0x05, IP cannot be obtained
  // - 0x06, wireless unstable
  // - 0xFF, WI-FI failure
  networkStatus[8] = isConnected ? 0x00 : 0x01;

  // Byte 9: Cloud service connection status:
  // - 0x00, connected to the cloud service center
  // - 0x01, not connected to the cloud service center
  // - 0x02, unstable internet connection
  // - 0x03, domain name resolution error
  // - 0x04, cloud service connection refused
  // - 0x05, cloud service maintenance
  // - 0xFF, cloud service failure
  networkStatus[9] = isConnected ? 0x00 : 0x01;

  // Byte 10: Direct LAN connection status
  // - 0x00: No connection/connection has been disconnected
  // - 0x01: connected/connected with mobile terminal
  networkStatus[10] = 0x00;

  // Byte 11 Number of TCP connections between the module and the mobile terminal
  networkStatus[11] = 0x00;

  // Byte 12 - 19 Reserved
}

void sendMessage(byte msgType, byte agreementVersion, byte payloadLength, byte *payload) {
  clearTxBuf();

  writeHeader(msgType, agreementVersion, payloadLength);
  memcpy(serialTxBuf, currentHeader, 10);
  memcpy(serialTxBuf + 10, payload, payloadLength);
  serialTxBuf[10 + payloadLength] = crc8(serialTxBuf + 10, payloadLength);
  serialTxBuf[10 + payloadLength + 1] = checksum(serialTxBuf, 10 + payloadLength + 1);

  Serial.write(serialTxBuf, 10 + payloadLength + 2);
}


================================================
FILE: src/esp8266-midea-dehumidifier/types.h
================================================
enum fanSpeed_t {
  low = 40,
  medium = 60,
  high = 80
};

enum dehumMode_t {
  setpoint = 1,
  continuous = 2,
  smart = 3,
  clothesDrying = 4
};

struct dehumidifierState_t { 
  boolean powerOn;
  dehumMode_t mode;
  fanSpeed_t fanSpeed;
  byte humiditySetpoint;
  byte currentHumidity;
  byte errorCode;
};


================================================
FILE: src/esp8266-midea-dehumidifier/wifi.h
================================================
char mqtt_server[80] = "example.tld";

char username[24] = "";
char password[24] = "";