[arduino code examples for T32M]-01 Turn ON/OFF OUTPUT

Code:
/*

 * Made by KinCony IoT: https://www.kincony.com

 *

 * This program controls a 32-channel relay board via two PCF8575 I/O expanders.

 * It sequentially turns on each relay (1~32) and then turns them off in a loop.

 * 

 * Pin Definitions:

 * - SDA: GPIO 48

 * - SCL: GPIO 47

 * 

 * PCF8575 I2C Addresses:

 * - 0x20: controls relays 1~16

 * - 0x21: controls relays 17~32

 * 

 * Delay Time:

 * - 200 milliseconds between switching relays

 */



#include <Wire.h>        // Include the Wire library for I2C communication

#include <PCF8575.h>     // Include the PCF8575 library to control the I/O expander



#define SDA_PIN 48           // Define the SDA pin

#define SCL_PIN 47           // Define the SCL pin

#define DELAY_TIME 200       // Define the delay time in milliseconds



// Set I2C addresses of the PCF8575 modules

#define I2C_ADDRESS1 0x20    // PCF8575 for relays 1~16

#define I2C_ADDRESS2 0x21    // PCF8575 for relays 17~32



// Create PCF8575 objects for each module

PCF8575 pcf8575_R1(I2C_ADDRESS1); // For relays 1~16

PCF8575 pcf8575_R2(I2C_ADDRESS2); // For relays 17~32



void setup() {

  // Initialize I2C communication

  Wire.begin(SDA_PIN, SCL_PIN);



  // Initialize serial communication for debugging (optional)

  Serial.begin(115200);

  Serial.println("PCF8575 32-Channel Relay Control: Starting...");



  // Initialize both PCF8575 modules

  pcf8575_R1.begin();

  pcf8575_R2.begin();



  // Turn off all relays initially (set all pins HIGH)

  for (int i = 0; i < 16; i++) {

    pcf8575_R1.write(i, HIGH); // Relays 1~16

    pcf8575_R2.write(i, HIGH); // Relays 17~32

  }

}



void loop() {

  // Sequentially turn on each relay (1~32)

  for (int i = 0; i < 32; i++) {

    if (i < 16) {

      pcf8575_R1.write(i, LOW);  // Turn on relay 1~16

    } else {

      pcf8575_R2.write(i - 16, LOW); // Turn on relay 17~32

    }

    delay(DELAY_TIME);

  }



  // Sequentially turn off each relay (1~32)

  for (int i = 0; i < 32; i++) {

    if (i < 16) {

      pcf8575_R1.write(i, HIGH); // Turn off relay 1~16

    } else {

      pcf8575_R2.write(i - 16, HIGH); // Turn off relay 17~32

    }

    delay(DELAY_TIME);

  }

}