Problem I2C @ ESP32-CAM and setup PCF8574A

[MAWMN]

/************************************************/
/***** I2C library tbv PCF8574 (XREEF) *****/
/***** I2C used chip = PCA8574A – addr 0x38 *****/
/***** when.. A0=x, A1=x, A2=x (x= GND) *****/
/************************************************/
/***** The ESP32-CAM I2C bus uses pins: *****/
/***** GPIO15 = SCL (ESP32_Cam) *****/
/***** GPIO14 = SDA (ESP32_Cam) *****/
/************************************************/

Problem I2C @ ESP32-CAM (AI thinker board)
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#include <Wire.h>

#define SCL 15 // IO15 GPIO15 HSPI_WSO HS2_CMD SD-Conn
#define SDA 14 // IO14 GPIO14 HSPI_CLK HS2_CLK SD-Conn

#include “PCF8574.h” // PCF8574 library @ 2.3.7
#define PCF_INTERRUPT 0 // IO0 GPIO0 CAM_PIN_XCLK or CSI_MCLK (Interrupt pin for Encoder & Switch)

// Pre formatted Header for the Interrupt (See Initialisation of updateEncoder Interrupt Below),
// necessary here because of the Interrupt Initialisation in the next Line
void IRAM_ATTR updateEncoder(); // ! *** IRAM_ATTR because this is the ISR !!!

// Initialize PCF-library Interrupt
PCF8574 pcf8574(0x38, PCF_INTERRUPT, updateEncoder); // for Default I2C Pins

Result :
Init pcf8574…begin(sda, scl) -> 21 22
Using interrupt pin (not all pin is interrupted)
STATUS –> 4
NOT OK <== NOT OK, wrong SDA and SCL port

==================================================
Now used after change :
#include <Wire.h>

#define SCL 15 // IO15 GPIO15 HSPI_WSO HS2_CMD SD-Conn
#define SDA 14 // IO14 GPIO14 HSPI_CLK HS2_CLK SD-Conn

#include “PCF8574.h” // PCF8574 library @ 2.3.7
#define PCF_INTERRUPT 0 // IO0 GPIO0 CAM_PIN_XCLK or CSI_MCLK (Interrupt pin for Encoder & Switch)

// Pre formatted Header for the Interrupt (See Initialisation of updateEncoder Interrupt Below),
// necessary here because of the Interrupt Initialisation in the next Line
void IRAM_ATTR updateEncoder(); // ! *** IRAM_ATTR because this is the ISR !!!

// Initialize PCF-library SDA & SCL
PCF8574 pcf8574(0x38, SDA, SCL);

// Question : HOW to setup also the “PCF_INTERRUPT”

Result:
Init pcf8574…begin(sda, scl) -> 14 15 <== this is OK now…But also need the Interrupt (How to do this)
STATUS –> 4
NOT OK <== Why still showing NOT OK

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