#include <DHTesp.h> // DHT for ESP32 library
#include <WiFi.h> // WiFi control for ESP32
//#include <ThingsBoard.h> // ThingsBoard SDK
#include "ThingsBoard.h"
#define COUNT_OF(x) ((sizeof(x)/sizeof(0[x])) / ((size_t)(!(sizeof(x) % sizeof(0[x])))))
#define WIFI_AP_NAME "Wokwi-GUEST"
#define WIFI_PASSWORD ""
#define THINGSBOARD_MQTT_SERVER "thingsboard.cloud"
#define THINGSBOARD_MQTT_ACESSTOKEN "AXcSfbrVK7gKIf36W6TL"
#define SERIAL_DEBUG_BAUD 115200
WiFiClient espClient;
ThingsBoard tb(espClient);
int status = WL_IDLE_STATUS;
// Array with LEDs that should be controlled from ThingsBoard, one by one
uint8_t leds_control[] = { 26, 33, 25 };
DHTesp dht;
#define DHT_PIN 15
// Main application loop delay
int quant = 20;
// Initial period of LED cycling.
int led_delay = 1000;
// Period of sending a temperature/humidity data.
int send_delay = 2000;
// Time passed after LED was turned ON, milliseconds.
int led_passed = 0;
// Time passed after temperature/humidity data was sent, milliseconds.
int send_passed = 0;
// Set to true if application is subscribed for the RPC messages.
bool subscribed = false;
// LED number that is currenlty ON.
int current_led = 0;
float temperature = 0;
float humidity = 0;
RPC_Response processDelayChange(const RPC_Data &data)
{
Serial.println("Received the set delay RPC method");
// Process data
led_delay = data;
Serial.print("Set new delay: ");
Serial.println(led_delay);
return String(led_delay);
}
RPC_Response processGetDelay(const RPC_Data &data)
{
Serial.println("Received the get value method");
return String(led_delay);
}
RPC_Response processSetGpioState(const RPC_Data &data)
{
Serial.println("Received the set GPIO RPC method");
int pin = data["pin"];
bool enabled = data["enabled"];
Serial.print("Setting LED ");
Serial.print(pin);
Serial.print(" to state ");
Serial.println(enabled);
// Red: 26, Green: 33, Blue: 25
digitalWrite(pin, enabled);
return String("{\"" + String(pin) + "\": " + String(enabled?"true":"false") + "}");
}
RPC_Response processGetGpioState(const RPC_Data &data)
{
Serial.println("Received the get GPIO RPC method");
String respStr = "{";
for (size_t i = 0; i < COUNT_OF(leds_control); ++i) {
int pin = leds_control[i];
Serial.print("Getting LED ");
Serial.print(pin);
Serial.print(" state ");
bool ledState = digitalRead(pin);
Serial.println(ledState);
respStr += String("\"" + String(pin) + "\": " + String(ledState?"true":"false") + ", ");
} //"pin" :
respStr = respStr.substring(0, respStr.length() - 2);
respStr += "}";
return respStr;
}
// RPC handlers
RPC_Callback callbacks[] = {
{ "setValue", processDelayChange },
{ "getValue", processGetDelay },
{ "setGpioStatus", processSetGpioState },
{ "getGpioStatus", processGetGpioState },
};
void setup() {
Serial.begin(SERIAL_DEBUG_BAUD);
WiFi.begin(WIFI_AP_NAME, WIFI_PASSWORD);
InitWiFi();
for (size_t i = 0; i < COUNT_OF(leds_control); ++i) {
pinMode(leds_control[i], OUTPUT);
}
// Initialize temperature sensor
dht.setup(DHT_PIN, DHTesp::DHT22);
}
void loop()
{
delay(quant);
led_passed += quant;
send_passed += quant;
// Reconnect to WiFi, if needed
if (WiFi.status() != WL_CONNECTED) {
reconnect();
return;
}
// Reconnect to ThingsBoard, if needed
if (!tb.connected()) {
subscribed = false;
// Connect to the ThingsBoard
Serial.print("Connecting MQTT to: ");
Serial.print(THINGSBOARD_MQTT_SERVER);
Serial.print(" with access token ");
Serial.println(THINGSBOARD_MQTT_ACESSTOKEN);
if (!tb.connect(THINGSBOARD_MQTT_SERVER, THINGSBOARD_MQTT_ACESSTOKEN)) {
Serial.println("Failed to connect");
return;
}
}
// Subscribe for RPC, if needed
if (!subscribed) {
Serial.println("Subscribing for RPC... ");
// Perform a subscription. All consequent data processing will happen in
// callbacks as denoted by callbacks[] array.
if (!tb.RPC_Subscribe(callbacks, COUNT_OF(callbacks))) {
Serial.println("Failed to subscribe for RPC");
return;
}
Serial.println("Subscribe done");
subscribed = true;
}
// Check if it is a time to send DHT22 temperature and humidity
if (send_passed > send_delay) {
Serial.println();
Serial.print("Sending data... ");
TempAndHumidity lastValues = dht.getTempAndHumidity();
if (isnan(lastValues.humidity) || isnan(lastValues.temperature)) {
Serial.println("Failed to read from DHT sensor!");
} else {
temperature = lastValues.temperature;
Serial.print("temperature: ");
Serial.print(temperature);
humidity = lastValues.humidity;
Serial.print(" humidity: ");
Serial.print(humidity);
tb.sendTelemetryFloat("temperature", temperature);
tb.sendTelemetryFloat("humidity", humidity);
}
send_passed = 0;
}
tb.loop();
}
void InitWiFi()
{
Serial.println("Connecting to AP ...");
// attempt to connect to WiFi network
WiFi.begin(WIFI_AP_NAME, WIFI_PASSWORD);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println(WiFi.localIP());
Serial.println("Connected to AP");
}
void reconnect() {
// Loop until we're reconnected
status = WiFi.status();
if ( status != WL_CONNECTED) {
WiFi.begin(WIFI_AP_NAME, WIFI_PASSWORD);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println(WiFi.localIP());
Serial.println("Connected to AP");
}
}