diff --git a/api/apibasic/cmdid.hpp b/api/apibasic/cmdid.hpp
index 71a9b86..ca1f297 100644
--- a/api/apibasic/cmdid.hpp
+++ b/api/apibasic/cmdid.hpp
@@ -88,8 +88,8 @@ typedef enum {
   /***********************************************************************************************************************
    *                                                        BOARD                                                        *
    ***********************************************************************************************************************/
-  kboard_read_io  = NEW_CMDID(103, 1),  // para:{}, ack:{4}
-  kboard_write_io = NEW_CMDID(103, 2),  // para:{}, ack:{4}
+  kboard_read_ext_io  = NEW_CMDID(103, 1),  // para:{}, ack:{4}
+  kboard_write_ext_io = NEW_CMDID(103, 2),  // para:{}, ack:{4}
 
 } cmdid_t;
 
diff --git a/api/zi_board.hpp b/api/zi_board.hpp
index ed210ef..2146368 100644
--- a/api/zi_board.hpp
+++ b/api/zi_board.hpp
@@ -10,7 +10,7 @@ using namespace std;
 class ZIBoard {
  public:
   virtual ~ZIBoard() {}
-  virtual int32_t board_read_io(int32_t ioindex, int32_t *val) = 0;
-  virtual int32_t board_write_io(int32_t ioindex, int32_t val) = 0;
+  virtual int32_t board_read_ext_io(int32_t ioindex, int32_t *val) = 0;
+  virtual int32_t board_write_ext_io(int32_t ioindex, int32_t val) = 0;
 };
 }  // namespace iflytop
\ No newline at end of file