ESP32 NETPIE Examples

This project contains ESP32 examples for connecting to Wi-Fi and NETPIE over MQTT.

The repository was reorganized from older .txt examples into cleaner source files that are easier to read, modify, and upload.

Files

• esp32_connect_netpie.ino Basic ESP32 example for connecting to Wi-Fi and NETPIE and subscribing to an MQTT topic
• send_dht_to_netpie.ino ESP32 example that reads DHT22 data and publishes temperature and humidity to NETPIE as JSON
• esp32_connect_netpie.txt Archived plain-text version of the basic connection example
• send_dht_to_netpie.txt Archived plain-text version of the DHT publishing example

Requirements

• ESP32 board
• Arduino IDE or PlatformIO
• Libraries:
  • WiFi (included with the ESP32 core)
  • PubSubClient
  • DHT sensor library

NETPIE Settings

Update these values in the .ino files before uploading:

const char* WIFI_SSID = "YOUR_WIFI_SSID";
const char* WIFI_PASSWORD = "YOUR_WIFI_PASSWORD";

const char* MQTT_CLIENT_ID = "YOUR_CLIENT_ID";
const char* MQTT_USERNAME = "YOUR_TOKEN";
const char* MQTT_PASSWORD = "YOUR_SECRET";

Also verify these settings:

• MQTT_BROKER is usually broker.netpie.io
• MQTT_PORT is usually 1883
• MQTT_TOPIC or MQTT_SUB_TOPIC should match your use case

Example Payload

send_dht_to_netpie.ino publishes data in this format:

{
  "temperature": 28.50,
  "humidity": 64.20
}

How To Use

1. Install the ESP32 board package in Arduino IDE.
2. Install the PubSubClient library.
3. Install the DHT sensor library.
4. Open the example file you want to use.
5. Replace the Wi-Fi, Client ID, Token, Secret, and topic values.
6. Select the correct board and serial port.
7. Upload the sketch to your ESP32.
8. Open Serial Monitor at 115200 baud.

Improvements From The Original

• Converted plain text examples into ready-to-use source files
• Used clearer constant names and function structure
• Separated Wi-Fi and MQTT connection logic
• Added reconnect handling for lost Wi-Fi or MQTT connections
• Added mqttClient.loop() to keep MQTT communication alive
• Replaced simple delay()-based publishing with a millis() timer

Note About File Extension

These examples use Arduino and ESP32 libraries and classes, which are C++-based rather than plain C.

Because of that, .ino or .cpp is a better fit than .c.