📺 Watch the Video View on YouTube --- Using ESP32 to communicate with Xiaomi flora (miflora) plant sensor using BLE and posting the values on MQTT se...
Using ESP32 to communicate with Xiaomi flora (miflora) plant sensor using BLE and posting the values on MQTT server. I also demonstrate the use of Home Assistant miflora sensor component.
Change ESP32 Partition: https://desire.giesecke.tk/index.php/2018/04/20/change-partition-size-arduino-ide/ Home Assistant miflora sensor: https://www.home-assistant.io/components/sensor.miflora/
Archived code from https://github.com/sidddy/flora below
config.h
// array of different xiaomi flora MAC addresses
char* FLORA_DEVICES[] = {
"C4:7C:8D:67:11:11",
"C4:7C:8D:67:22:22",
"C4:7C:8D:67:33:33"
};
// sleep between to runs in seconds
#define SLEEP_DURATION 30 * 60
// emergency hibernate countdown in seconds
#define EMERGENCY_HIBERNATE 3 * 60
// how often should the battery be read - in run count
#define BATTERY_INTERVAL 6
// how often should a device be retried in a run when something fails
#define RETRY 3
const char* WIFI_SSID = "ssid";
const char* WIFI_PASSWORD = "password";
// MQTT topic gets defined by "<MQTT_BASE_TOPIC>/<MAC_ADDRESS>/<property>"
// where MAC_ADDRESS is one of the values from FLORA_DEVICES array
// property is either temperature, moisture, conductivity, light or battery
const char* MQTT_HOST = "10.10.10.1";
const int MQTT_PORT = 1883;
const char* MQTT_CLIENTID = "miflora-client";
const char* MQTT_USERNAME = "username";
const char* MQTT_PASSWORD = "password";
const String MQTT_BASE_TOPIC = "flora";
const int MQTT_RETRY_WAIT = 5000;
flora.ino
/**
A BLE client for the Xiaomi Mi Plant Sensor, pushing measurements to an MQTT server.
See https://github.com/nkolban/esp32-snippets/blob/master/Documentation/BLE%20C%2B%2B%20Guide.pdf
on how bluetooth low energy and the library used are working.
See https://github.com/ChrisScheffler/miflora/wiki/The-Basics for details on how the
protocol is working.
MIT License
Copyright (c) 2017 Sven Henkel
Multiple units reading by Grega Lebar 2018
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.
*/
#include "BLEDevice.h"
#include <WiFi.h>
#include <PubSubClient.h>
#include "config.h"
// boot count used to check if battery status should be read
RTC_DATA_ATTR int bootCount = 0;
// device count
static int deviceCount = sizeof FLORA_DEVICES / sizeof FLORA_DEVICES[0];
// the remote service we wish to connect to
static BLEUUID serviceUUID("00001204-0000-1000-8000-00805f9b34fb");
// the characteristic of the remote service we are interested in
static BLEUUID uuid_version_battery("00001a02-0000-1000-8000-00805f9b34fb");
static BLEUUID uuid_sensor_data("00001a01-0000-1000-8000-00805f9b34fb");
static BLEUUID uuid_write_mode("00001a00-0000-1000-8000-00805f9b34fb");
TaskHandle_t hibernateTaskHandle = NULL;
WiFiClient espClient;
PubSubClient client(espClient);
void connectWifi() {
Serial.println("Connecting to WiFi...");
WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("");
}
void disconnectWifi() {
WiFi.disconnect(true);
Serial.println("WiFi disonnected");
}
void connectMqtt() {
Serial.println("Connecting to MQTT...");
client.setServer(MQTT_HOST, MQTT_PORT);
while (!client.connected()) {
if (!client.connect(MQTT_CLIENTID, MQTT_USERNAME, MQTT_PASSWORD)) {
Serial.print("MQTT connection failed:");
Serial.print(client.state());
Serial.println("Retrying...");
delay(MQTT_RETRY_WAIT);
}
}
Serial.println("MQTT connected");
Serial.println("");
}
void disconnectMqtt() {
client.disconnect();
Serial.println("MQTT disconnected");
}
BLEClient* getFloraClient(BLEAddress floraAddress) {
BLEClient* floraClient = BLEDevice::createClient();
if (!floraClient->connect(floraAddress)) {
Serial.println("- Connection failed, skipping");
return nullptr;
}
Serial.println("- Connection successful");
return floraClient;
}
BLERemoteService* getFloraService(BLEClient* floraClient) {
BLERemoteService* floraService = nullptr;
try {
floraService = floraClient->getService(serviceUUID);
}
catch (...) {
// something went wrong
}
if (floraService == nullptr) {
Serial.println("- Failed to find data service");
}
else {
Serial.println("- Found data service");
}
return floraService;
}
bool forceFloraServiceDataMode(BLERemoteService* floraService) {
BLERemoteCharacteristic* floraCharacteristic;
// get device mode characteristic, needs to be changed to read data
Serial.println("- Force device in data mode");
floraCharacteristic = nullptr;
try {
floraCharacteristic = floraService->getCharacteristic(uuid_write_mode);
}
catch (...) {
// something went wrong
}
if (floraCharacteristic == nullptr) {
Serial.println("-- Failed, skipping device");
return false;
}
// write the magic data
uint8_t buf[2] = {0xA0, 0x1F};
floraCharacteristic->writeValue(buf, 2, true);
delay(500);
return true;
}
bool readFloraDataCharacteristic(BLERemoteService* floraService, String baseTopic) {
BLERemoteCharacteristic* floraCharacteristic = nullptr;
// get the main device data characteristic
Serial.println("- Access characteristic from device");
try {
floraCharacteristic = floraService->getCharacteristic(uuid_sensor_data);
}
catch (...) {
// something went wrong
}
if (floraCharacteristic == nullptr) {
Serial.println("-- Failed, skipping device");
return false;
}
// read characteristic value
Serial.println("- Read value from characteristic");
std::string value;
try{
value = floraCharacteristic->readValue();
}
catch (...) {
// something went wrong
Serial.println("-- Failed, skipping device");
return false;
}
const char *val = value.c_str();
Serial.print("Hex: ");
for (int i = 0; i < 16; i++) {
Serial.print((int)val[i], HEX);
Serial.print(" ");
}
Serial.println(" ");
int16_t* temp_raw = (int16_t*)val;
float temperature = (*temp_raw) / ((float)10.0);
Serial.print("-- Temperature: ");
Serial.println(temperature);
int moisture = val[7];
Serial.print("-- Moisture: ");
Serial.println(moisture);
int light = val[3] + val[4] * 256;
Serial.print("-- Light: ");
Serial.println(light);
int conductivity = val[8] + val[9] * 256;
Serial.print("-- Conductivity: ");
Serial.println(conductivity);
if (temperature > 200) {
Serial.println("-- Unreasonable values received, skip publish");
return false;
}
char buffer[64];
snprintf(buffer, 64, "%f", temperature);
client.publish((baseTopic + "temperature").c_str(), buffer);
snprintf(buffer, 64, "%d", moisture);
client.publish((baseTopic + "moisture").c_str(), buffer);
snprintf(buffer, 64, "%d", light);
client.publish((baseTopic + "light").c_str(), buffer);
snprintf(buffer, 64, "%d", conductivity);
client.publish((baseTopic + "conductivity").c_str(), buffer);
return true;
}
bool readFloraBatteryCharacteristic(BLERemoteService* floraService, String baseTopic) {
BLERemoteCharacteristic* floraCharacteristic = nullptr;
// get the device battery characteristic
Serial.println("- Access battery characteristic from device");
try {
floraCharacteristic = floraService->getCharacteristic(uuid_version_battery);
}
catch (...) {
// something went wrong
}
if (floraCharacteristic == nullptr) {
Serial.println("-- Failed, skipping battery level");
return false;
}
// read characteristic value
Serial.println("- Read value from characteristic");
std::string value;
try{
value = floraCharacteristic->readValue();
}
catch (...) {
// something went wrong
Serial.println("-- Failed, skipping battery level");
return false;
}
const char *val2 = value.c_str();
int battery = val2[0];
char buffer[64];
Serial.print("-- Battery: ");
Serial.println(battery);
snprintf(buffer, 64, "%d", battery);
client.publish((baseTopic + "battery").c_str(), buffer);
return true;
}
bool processFloraService(BLERemoteService* floraService, char* deviceMacAddress, bool readBattery) {
// set device in data mode
if (!forceFloraServiceDataMode(floraService)) {
return false;
}
String baseTopic = MQTT_BASE_TOPIC + "/" + deviceMacAddress + "/";
bool dataSuccess = readFloraDataCharacteristic(floraService, baseTopic);
bool batterySuccess = true;
if (readBattery) {
batterySuccess = readFloraBatteryCharacteristic(floraService, baseTopic);
}
return dataSuccess && batterySuccess;
}
bool processFloraDevice(BLEAddress floraAddress, char* deviceMacAddress, bool getBattery, int tryCount) {
Serial.print("Processing Flora device at ");
Serial.print(floraAddress.toString().c_str());
Serial.print(" (try ");
Serial.print(tryCount);
Serial.println(")");
// connect to flora ble server
BLEClient* floraClient = getFloraClient(floraAddress);
if (floraClient == nullptr) {
return false;
}
// connect data service
BLERemoteService* floraService = getFloraService(floraClient);
if (floraService == nullptr) {
floraClient->disconnect();
return false;
}
// process devices data
bool success = processFloraService(floraService, deviceMacAddress, getBattery);
// disconnect from device
floraClient->disconnect();
return success;
}
void hibernate() {
esp_sleep_enable_timer_wakeup(SLEEP_DURATION * 1000000ll);
Serial.println("Going to sleep now.");
delay(100);
esp_deep_sleep_start();
}
void delayedHibernate(void *parameter) {
delay(EMERGENCY_HIBERNATE*1000); // delay for five minutes
Serial.println("Something got stuck, entering emergency hibernate...");
hibernate();
}
void setup() {
// all action is done when device is woken up
Serial.begin(115200);
delay(1000);
// increase boot count
bootCount++;
// create a hibernate task in case something gets stuck
xTaskCreate(delayedHibernate, "hibernate", 4096, NULL, 1, &hibernateTaskHandle);
Serial.println("Initialize BLE client...");
BLEDevice::init("");
BLEDevice::setPower(ESP_PWR_LVL_P7);
// connecting wifi and mqtt server
connectWifi();
connectMqtt();
// check if battery status should be read - based on boot count
bool readBattery = ((bootCount % BATTERY_INTERVAL) == 0);
// process devices
for (int i=0; i<deviceCount; i++) {
int tryCount = 0;
char* deviceMacAddress = FLORA_DEVICES[i];
BLEAddress floraAddress(deviceMacAddress);
while (tryCount < RETRY) {
tryCount++;
if (processFloraDevice(floraAddress, deviceMacAddress, readBattery, tryCount)) {
break;
}
delay(1000);
}
delay(1500);
}
// disconnect wifi and mqtt
disconnectWifi();
disconnectMqtt();
// delete emergency hibernate task
vTaskDelete(hibernateTaskHandle);
// go to sleep now
hibernate();
}
void loop() {
/// we're not doing anything in the loop, only on device wakeup
delay(10000);
}