Write & Read digital logic via PCA9557 8-bit I/O expander
#include <Arduino.h>
#include <Wire.h>
#include <PCA9557.h>
PCA9557 io(0x19, &Wire); // 0x19 for iFarm4G board
void setup() {
Serial.begin(115200);
Wire.begin();
io.pinMode(0, INPUT); // Config IO0 of PCA9557 to INPUT mode
io.pinMode(1, OUTPUT); // Config IO1 of PCA9557 to OUTPUT mode
}
void loop() {
io.digitalWrite(1, HIGH);
delay(1000);
io.digitalWrite(1, LOW);
delay(1000);
// Serial.println("D0 = " + String(io.digitalRead(0)));
}