diff --git a/PCF8574/PCF8574.h b/PCF8574/PCF8574.h
index 5e6ffa2..da52fc5 100644
--- a/PCF8574/PCF8574.h
+++ b/PCF8574/PCF8574.h
@@ -29,6 +29,7 @@ class PCF8574
   void begin();
   void write(uint8_t pin, uint8_t value);
   uint8_t read(uint8_t pin);
+  enum PINS {P0 = 0, P1, P2, P3, P4, P5, P6, P7};
 };
 
 #endif
\ No newline at end of file