[Arduino code for KC868-A32 Pro]-01 Control relay by XL9535

Code:
#include <PCA95x5.h>



PCA9555 ioex;



void setup() {

    Serial.begin(115200);

    delay(100);



    Wire.begin(11,10,100000);

    ioex.attach(Wire,0x21);

    ioex.polarity(PCA95x5::Polarity::ORIGINAL_ALL);

    ioex.direction(PCA95x5::Direction::OUT_ALL);

    ioex.write(PCA95x5::Level::H_ALL);

    delay(2000);

}



void loop() {

    for (size_t i = 0; i < 16; ++i) {

        Serial.print("set port low: ");  //turn ON relay

        Serial.println(i);



        ioex.write((PCA95x5::Port::Port)i, PCA95x5::Level::L);

        Serial.println(ioex.read(), BIN);

        delay(500);

    }



    for (size_t i = 0; i < 16; ++i) {

        Serial.print("set port high: "); //turn OFF relay

        Serial.println(i);



        ioex.write((PCA95x5::Port::Port)i, PCA95x5::Level::H);

        Serial.println(ioex.read(), BIN);

        delay(500);

    }

}