diff --git a/iflytop_canbus_protocol.hpp b/iflytop_canbus_protocol.hpp
index 407e386..541b959 100644
--- a/iflytop_canbus_protocol.hpp
+++ b/iflytop_canbus_protocol.hpp
@@ -9,16 +9,16 @@ extern "C" {
 
 /**
  * @brief 消息格式 12bit from,1bit emergency
- *
+ * H                                    L
  * [1] [4bit]  [8bit] [8bit]  [4bit/4bit]
  *          ,   from    to    frameNum/frameId
  */
 
 typedef struct {
-  uint8_t pad;
-  uint8_t from;
-  uint8_t to;
   uint8_t frameNumAndFrameId;
+  uint8_t to;
+  uint8_t from;
+  uint8_t pad;
 } zcanid_t;
 
 typedef struct {