This sketch demonstrates how to use the Grove relay module.

05.50_-_Grove_relay_module.ino

/*  05.50 - Grove Relay module
 *   
   This sketch demonstrates how to use the Grove relay module.

   This sketch is identical to the one from 05.10, that we used with the
   LED kit module. We'll use a digital pin to energise the relay coil, and
   drive a large electrical load.

   The load can be anything the draws less than 10A current and 30V.

   For example, you can drive a fan, an LED strip, or an electro-magnet.

   Connect the relay module to Grove connector D4.

   Connect the electrical load to the screw terminal of the relay board, like 
   a switch. Please watch the video in lecture 05.50 for a demonstration on 
   how to do this.
   
   Components
   ----------
    
    - Grove Base Shield
    - An Arduino Uno compatible board (such as Arduino/Genuino Uno or Seeeduino)
    - Grove LED relay module
    - An electrical load, such as an LED strip, and its external power supply.
    - One Grove cable
    
    IDE
    ---
    
    Arduino IDE
    
    Libraries
    ---------
    
    - 
    
    Connections
    -----------
    
    Use a Grove cable to connect the module to Base Shield connector D4.
    
    Other information
    -----------------
    
    - Use this sketch along side the video lecture 05.50 of Grove For Busy People
    - Grove component: https://txplo.re/7fb98
    
    Github Gist
    -----------
    <script src="https://gist.github.com/futureshocked/c0ecc83ca188c70878ec8c48415ca9b6.js"></script>

    https://gist.github.com/futureshocked/c0ecc83ca188c70878ec8c48415ca9b6
    
    For course information, please go to https://techexplorations.com/product/grove-for-busy-people/
        
    Created on July 5 2019 by Peter Dalmaris
*/

const int ledPin = 4; 

// Connect the LED to Arduino digital pin 4, Grove socket D4
void setup() {
  // initialize ledPin as an output.
  pinMode(ledPin, OUTPUT);
}

// the loop function runs over and over again forever
void loop() {
  digitalWrite(ledPin, HIGH);   // turn the LED on (HIGH is the voltage level)
  delay(1000);                       // wait for a second
  digitalWrite(ledPin, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);                       // wait for a second
}