diff --git a/src/chip/CH422G.h b/src/chip/CH422G.h
index 7d3cd18..114d909 100644
--- a/src/chip/CH422G.h
+++ b/src/chip/CH422G.h
@@ -65,6 +65,8 @@ class ESP_IOExpander_CH422G: public ESP_IOExpander {
     /**
      * @brief Begin IO expander
      *
+     * @note  The driver initialization by default sets CH422G's IO0-7 to output high-level mode.
+     *
      */
     void begin(void) override;
 
@@ -83,6 +85,10 @@ class ESP_IOExpander_CH422G: public ESP_IOExpander {
     /**
      * @brief Enable IO0-7 input mode
      *
+     * @note  The driver initialization by default sets CH422G's IO0-7 to output high-level mode.
+     * @note  Since the input/output mode of CH422G's IO0-7 must remain consistent, the driver will only set IO0-7 to
+     *        input mode when it determines that all pins are configured as input.
+     *
      */
     void enableAllIO_Input(void);