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Your First VwireIOT Project

Build a complete temperature and humidity monitor with a live dashboard in under 10 minutes.

What you'll build​

ESP32 + DHT22 ──MQTT/TLS──▶ VwireIOT ──▶ Dashboard
                                           ├── Value Display: Temperature (V0)
                                           ├── Value Display: Humidity (V1)
                                           ├── Gauge: Humidity % (V1)
                                           └── Graph: 24h temperature trend (V0)

Hardware needed​

  • ESP32 development board (any variant)
  • DHT22 temperature/humidity sensor
  • 10 kΩ pull-up resistor
  • Breadboard + jumper wires

Wiring:

DHT22 pinESP32 pin
VCC3.3 V
DATAGPIO 4 (with 10 kΩ pull-up to 3.3 V)
GNDGND

Step 1: Create a device​

  1. Log in to the VwireIOT Dashboard
  2. Go to Devices → Add Device, name it ESP32 DHT22, and click Create
  3. Open the device and copy both:
    • Auth Token — secret key embedded in firmware
    • Device ID — the device's identifier (e.g. VU-XXXXXX)

Step 2: Flash the firmware​

Install the required libraries in Arduino IDE (Library Manager):

  • Vwire — search Vwire
  • DHT sensor library — search DHT sensor library by Adafruit
  • PubSubClient and ArduinoJson (Vwire dependencies)

Create a new sketch:

#include <Vwire.h>
#include <DHT.h>

// WiFi credentials
const char* WIFI_SSID     = "YOUR_WIFI_SSID";
const char* WIFI_PASSWORD = "YOUR_WIFI_PASSWORD";

// From device settings in the dashboard
const char* AUTH_TOKEN = "YOUR_AUTH_TOKEN";
const char* DEVICE_ID  = "YOUR_DEVICE_ID";   // e.g. VU-ABC123

// DHT sensor
#define DHT_PIN  4
#define DHT_TYPE DHT22
DHT dht(DHT_PIN, DHT_TYPE);

// Called when connected to Vwire cloud
VWIRE_CONNECTED() {
  Serial.println("Connected to VwireIOT!");
  Vwire.sync(V0, V1);  // Request last stored values from cloud
}

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

  // Configure Vwire (uses mqtt.vwire.io:8883 TLS by default)
  Vwire.config(AUTH_TOKEN);
  Vwire.setDeviceId(DEVICE_ID);

  // Connect to WiFi and Vwire cloud
  Vwire.begin(WIFI_SSID, WIFI_PASSWORD);
}

void loop() {
  Vwire.run();  // Must be called every iteration

  static unsigned long lastRead = 0;
  if (Vwire.connected() && millis() - lastRead >= 5000) {
    lastRead = millis();

    float temp = dht.readTemperature();
    float hum  = dht.readHumidity();

    if (!isnan(temp) && !isnan(hum)) {
      Vwire.virtualSend(V0, temp);   // V0 = Temperature
      Vwire.virtualSend(V1, hum);    // V1 = Humidity

      Serial.printf("Temp: %.1f°C  Hum: %.1f%%\n", temp, hum);
    }
  }
}

Flash to your ESP32. Open Serial Monitor at 115200 baud and wait for:

Connected to VwireIOT!
Temp: 23.5°C  Hum: 58.2%

Step 3: Create a project​

  1. In the dashboard, go to Projects → New Project, name it Home Monitor, and click Create
  2. Click Edit Dashboard to enter edit mode

Step 4: Build the dashboard​

Temperature display (V0)​

  1. + Add Widget → Value Display
  2. Device: ESP32 DHT22, Pin: V0
  3. Suffix: °C, Label: Temperature
  4. Click Save — live temperature appears immediately

Humidity display (V1)​

  1. + Add Widget → Value Display
  2. Device: ESP32 DHT22, Pin: V1
  3. Suffix: %, Label: Humidity

Humidity gauge​

  1. + Add Widget → Gauge
  2. Device: ESP32 DHT22, Pin: V1
  3. Min: 0, Max: 100, Label: Humidity

Temperature history chart​

  1. + Add Widget → Graph
  2. Device: ESP32 DHT22, Pin: V0
  3. Duration: 24h, Label: Temperature trend

Step 5: Set up an alert​

Get notified when temperature exceeds a threshold:

  1. Go to Alerts in the project
  2. Click + Add Alert
  3. Set: Device ESP32 DHT22, Pin V0, Condition greater than, Value 30
  4. Choose delivery: Push notification, Email, or both

The alert triggers automatically when the device pushes a reading above 30 °C.

Result​

Your dashboard now shows live temperature and humidity readings and a 24-hour trend chart. Data is stored per your plan's retention period and available for graphing and export.

Next steps​

Result​

Your dashboard now shows live temperature, humidity, a gauge, and a historical chart. All data is stored and available for up to 30 days on the free plan.

Next steps​