#include #include "PCF8574.h" PCF8574 expander; void setup() { Serial.begin(9600); expander.begin(0x20); /* Setup some PCF8574 pins for demo */ expander.pinMode(0, OUTPUT); expander.pinMode(1, OUTPUT); expander.pinMode(2, OUTPUT); expander.pinMode(3, INPUT_PULLUP); /* Blink hardware LED for debug */ digitalWrite(13, HIGH); /* Toggle PCF8574 output 0 for demo */ expander.toggle(); /* Blink hardware LED for debug */ digitalWrite(13, LOW); } void loop() { }