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1. Mrzaizai2k - AI (NEW)
2. Mrzaizai2k (old)

LED Control with Android app via Wifi to NodeMCU and Arduino Uno then send data back to the app.

YOUTUBE LINK: IOT with Arduino Uno, NodeMCU, MIT app _ Mrzaizai2k

My Arduino code, circut diagram & apk. file (MIT App): https://drive.google.com/open?id=1pGBlIQ7Rhmqb2475-qOyBZvDtrR75e32

References:

1. How To Build Custom Android App for your Arduino Project using MIT App Inventor: https://www.youtube.com/watch?time_continue=69&v=o-YVvxYiSuk&feature=emb_logo
2. MIT App Inventor: http://appinventor.mit.edu/
3. How to make SoftwareSerial Communication between Arduino Uno and NodeMCU: https://www.youtube.com/watch?v=BfUtpScdQ9Y
4. Dự án xe điều khiển từ xa qua Internet với iNut Cảm biến kết nối với wifi trong nhà hoặc USB Wifi 3G: http://arduino.vn/tutorial/5781-du-xe-dieu-khien-tu-xa-qua-internet-voi-inut-cam-bien-ket-noi-voi-wifi-trong-nha-hoac
5. MIT APP INVENTOR 2 -nodemcu wifi car control app: https://www.youtube.com/watch?v=nVYCTKWcq24&t=25s
6. NodeMCU Server | Control via WebBrowser | RoboShala Hindi: https://www.youtube.com/watch?v=rs2CwV8ilPI&t=12s

1. Ledon_Uno 1.1 Overview 1.2 How It Works
2. Ledonwifi 2.1 Overview 2.2 How It Works

The Ledon_Uno Arduino sketch integrates an ultrasonic sensor (HC-SR04) and an LED controlled by an Arduino Uno. It communicates with a NodeMCU (ESP8266) via SoftwareSerial. The ultrasonic sensor measures distance, and the LED is controlled based on commands received from Ledonwifi.

1. Setup:

   • The HC-SR04 ultrasonic sensor is connected to pins 8 (trig) and 7 (echo).
   • An LED is connected to pin 12.
   • Communication between Arduino Uno and NodeMCU is established using SoftwareSerial on pins 3 (RX) and 2 (TX).
   • OpenAI API credentials are set up.

2. Distance Measurement:

   • The distance() function measures the distance using the HC-SR04 sensor and returns the result in centimeters.

3. Communication with NodeMCU:

   • The Arduino Uno sends the distance data to NodeMCU via SoftwareSerial.
   • NodeMCU processes the data and controls the LED based on specific commands.

4. Data Transmission:

   • The Arduino Uno continuously measures and sends the distance data to NodeMCU.
   • NodeMCU toggles the LED on or off based on commands received from Ledonwifi.

The Ledonwifi Arduino sketch runs on a NodeMCU (ESP8266) and serves as a web server. It receives commands via HTTP requests to control the LED on Ledon_Uno and obtain distance information.

1. Setup:

   • NodeMCU is connected to a Wi-Fi network.
   • A web server is set up on NodeMCU.

2. LED Control:

   • Commands like "LEDon" and "LEDoff" are received via HTTP requests.
   • The corresponding functions (LEDon() and LEDoff()) are executed to control the LED on Ledon_Uno.

3. Distance Information:

   • The "distance" command is processed to obtain distance data from Ledon_Uno.
   • The data is sent back to the client (browser) that made the HTTP request.

4. HTTP Server Handling:

   • The server continuously listens for client connections and responds to requests.

Note: Ensure that the Wi-Fi credentials in Ledonwifi match your network settings, and the OpenAI API key in Ledon_Uno is secure and not publicly shared.