[arduino code examples for F24]-02 Read digital input ports state

Code:
/*

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

 *

 * Description:

 * This Arduino program reads the state of two 16-channel PCF8575 I/O expanders

 * and prints the state of all input pins (1-24) to the Serial Monitor. The state of 

 * each pin is represented as a bit in a 24-bit value, where each bit corresponds 

 * to an input pin. The program prints the input state in binary format.

 *

 * Pin Definitions:

 * - SDA: GPIO 8

 * - SCL: GPIO 18

 * - PCF8575 I2C Address: 0x24 for inputs 1-16, 0x26 for inputs 17-24

 */



#include "Arduino.h"

#include "PCF8575.h"



// Define I2C pins

#define I2C_SDA 8  // Define SDA pin

#define I2C_SCL 18  // Define SCL pin



// Set I2C addresses

PCF8575 pcf8575_IN1(0x24); // The I2C address of the first PCF8575 (inputs 1-16)

PCF8575 pcf8575_IN2(0x26); // The I2C address of the second PCF8575 (inputs 17-24)



void setup() {

    Serial.begin(115200);



    // Initialize I2C communication

    Wire.begin(I2C_SDA, I2C_SCL); // Initialize I2C with defined SDA and SCL pins



    // Initialize both PCF8575 modules

    pcf8575_IN1.begin();

    pcf8575_IN2.begin();



    Serial.println("KinCony F24 24 channel input state 0:ON  1:OFF");

}



void loop() {

    uint32_t state = 0; // Use a 32-bit variable to store the state of all 24 pins



    // Read the state of each pin from the first PCF8575 (inputs 1-16)

    for (int pin = 0; pin < 16; pin++) {

        if (pcf8575_IN1.read(pin)) {

            state |= (1UL << pin); // Set the bit for the active pin (inputs 1-16)

        }

    }



    // Read the state of each pin from the second PCF8575 (inputs 17-24, corresponding to pins 0-7)

    for (int pin = 0; pin < 8; pin++) {

        if (pcf8575_IN2.read(pin)) {

            state |= (1UL << (pin + 16)); // Set the bit for the active pin (inputs 17-24)

        }

    }



    // Print the state of all 24 inputs in binary format

    Serial.print("Input state: ");

    Serial.println(state, BIN); // Print the state of inputs in binary



    delay(500); // Delay 500ms

}