diff --git a/include/zh_pcf8574.h b/include/zh_pcf8574.h
index ff29a30..10e0b5c 100755
--- a/include/zh_pcf8574.h
+++ b/include/zh_pcf8574.h
@@ -112,9 +112,9 @@ extern "C"
      */
     typedef struct
     {
-        uint8_t i2c_address; /*!< The i2c address of PCF8574 expander that caused the interrupt. */
-        uint8_t gpio_number; /*!< The GPIO that caused the interrupt. */
-        bool gpio_level;     /*!< The GPIO level that caused the interrupt. */
+        uint8_t i2c_address;               /*!< The i2c address of PCF8574 expander that caused the interrupt. */
+        zh_pcf8574_gpio_num_t gpio_number; /*!< The GPIO that caused the interrupt. */
+        bool gpio_level;                   /*!< The GPIO level that caused the interrupt. */
     } zh_pcf8574_event_on_isr_t;
 
     /**