Code:
/*KC868-E16S pcf8574 -digital input code*/
#include "Arduino.h"
#include "PCF8574.h"
// Set i2c address
PCF8574 pcf8574_IN1(0x22,16,15);
PCF8574 pcf8574_IN2(0x24,16,15);
void setup()
{
Serial.begin(115200);
delay(1000);
pcf8574_IN1.begin();
pcf8574_IN2.begin();
pcf8574_IN1.pinMode(P0, INPUT);
pcf8574_IN1.pinMode(P1, INPUT);
pcf8574_IN1.pinMode(P2, INPUT);
pcf8574_IN1.pinMode(P3, INPUT);
pcf8574_IN1.pinMode(P4, INPUT);
pcf8574_IN1.pinMode(P5, INPUT);
pcf8574_IN1.pinMode(P6, INPUT);
pcf8574_IN1.pinMode(P7, INPUT);
pcf8574_IN2.pinMode(P0, INPUT);
pcf8574_IN2.pinMode(P1, INPUT);
pcf8574_IN2.pinMode(P2, INPUT);
pcf8574_IN2.pinMode(P3, INPUT);
pcf8574_IN2.pinMode(P4, INPUT);
pcf8574_IN2.pinMode(P5, INPUT);
pcf8574_IN2.pinMode(P6, INPUT);
pcf8574_IN2.pinMode(P7, INPUT);
}
void loop()
{
if (pcf8574_IN1.digitalRead(P0)==0) {Serial.println("KEY1 PRESSED");}delay(100);
if (pcf8574_IN1.digitalRead(P1)==0) {Serial.println("KEY2 PRESSED");}delay(100);
if (pcf8574_IN1.digitalRead(P2)==0) {Serial.println("KEY3 PRESSED");}delay(100);
if (pcf8574_IN1.digitalRead(P3)==0) {Serial.println("KEY4 PRESSED");}delay(100);
if (pcf8574_IN1.digitalRead(P4)==0) {Serial.println("KEY5 PRESSED");}delay(100);
if (pcf8574_IN1.digitalRead(P5)==0) {Serial.println("KEY6 PRESSED");}delay(100);
if (pcf8574_IN1.digitalRead(P6)==0) {Serial.println("KEY7 PRESSED");}delay(100);
if (pcf8574_IN1.digitalRead(P7)==0) {Serial.println("KEY8 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P0)==0) {Serial.println("KEY9 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P1)==0) {Serial.println("KEY10 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P2)==0) {Serial.println("KEY11 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P3)==0) {Serial.println("KEY12 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P4)==0) {Serial.println("KEY13 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P5)==0) {Serial.println("KEY14 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P6)==0) {Serial.println("KEY15 PRESSED");}delay(100);
if (pcf8574_IN2.digitalRead(P7)==0) {Serial.println("KEY16 PRESSED");}delay(100);
}