diff --git a/bspMCU/l_stm32.c b/bspMCU/l_stm32.c
index 230cac7..06cc3ed 100644
--- a/bspMCU/l_stm32.c
+++ b/bspMCU/l_stm32.c
@@ -743,25 +743,20 @@ int luaopen_stm32(lua_State *L)
 #endif
     
     lua_setglobal(L, "st");
+    lua_add_help_entry("st", "STM32 hardware module (Pin, LED, delay, etc.)");
 
-    lua_pushcfunction(L, l_reboot);
-    lua_setglobal(L, "reboot"); // reboot = l_reboot
+    lua_register_help(L, "reboot", l_reboot, "Reset the system");
 
 #ifdef USE_FREERTOS
-    lua_pushcfunction(L, l_ps);
-    lua_setglobal(L, "ps"); // ps = l_ps
-
-    lua_pushcfunction(L, l_free);
-    lua_setglobal(L, "free"); // ps = l_ps
+    lua_register_help(L, "ps", l_ps, "Show task list");
+    lua_register_help(L, "free", l_free, "Show heap size");
 #endif
 
 #ifdef USE_LWIP
-    lua_pushcfunction(L, l_lwip);
-    lua_setglobal(L, "lwip"); // lwip = l_lwip
+    lua_register_help(L, "lwip", l_lwip, "Display lwIP stats");
 #endif
 
-    lua_pushcfunction(L, l_sendto);
-    lua_setglobal(L, "sendto"); // sendto = l_sendto
+    lua_register_help(L, "sendto", l_sendto, "Send msg: sendto(dst,id,data)");
 
     return 1;
 }
diff --git a/lua/lua.c b/lua/lua.c
index f74dfeb..04b3a43 100644
--- a/lua/lua.c
+++ b/lua/lua.c
@@ -17,6 +17,9 @@ static size_t len = 0;
 static size_t cursor_pos = 0;
 static int escape_mode = 0; // 0: 正常, 1: 收到 ESC, 2: 收到 ESC [
 
+static lua_help_entry_t help_entries[MAX_HELP_ENTRIES];
+static int help_entry_count = 0;
+
 static void add_to_history(const char *cmd) 
 {
     if (cmd == NULL || strlen(cmd) == 0) return;
@@ -397,6 +400,39 @@ static char *readline(const char *_pcPrompt, char *_pcBuffer, int _iSize, int _i
 
 extern int luaopen_stm32(lua_State *L);
 
+void lua_register_help(lua_State *L, const char *name, lua_CFunction func, const char *description)
+{
+    lua_pushcfunction(L, func);
+    lua_setglobal(L, name);
+
+    if (help_entry_count < MAX_HELP_ENTRIES)
+    {
+        help_entries[help_entry_count].name = name;
+        help_entries[help_entry_count].description = description;
+        help_entry_count++;
+    }
+}
+
+void lua_add_help_entry(const char *name, const char *description)
+{
+    if (help_entry_count < MAX_HELP_ENTRIES)
+    {
+        help_entries[help_entry_count].name = name;
+        help_entries[help_entry_count].description = description;
+        help_entry_count++;
+    }
+}
+
+static int l_help(lua_State *L)
+{
+    lua_print("Available commands:\n");
+    for (int i = 0; i < help_entry_count; i++)
+    {
+        lua_print("  %-16s %s\n", help_entries[i].name, help_entries[i].description);
+    }
+    return 0;
+}
+
 static int l_name(lua_State *L)
 {
     lua_print("%s\n", Rd_GetBuildTime());
@@ -405,8 +441,8 @@ static int l_name(lua_State *L)
 
 static int luaopen_default(lua_State *L)
 {
-    lua_pushcfunction(L, l_name);
-    lua_setglobal(L, "name"); // name = l_name
+    lua_register_help(L, "help", l_help, "Show this help message");
+    lua_register_help(L, "name", l_name, "Show build time");
     return 0;
 }
 
@@ -415,6 +451,7 @@ int lua_init(lua_output _lua_print)
     if (NULL == _lua_print) return -1;
     lua_print = _lua_print;
 
+    help_entry_count = 0;
     buffer_len = 0;
     capacity = 256;
     len = 0;
diff --git a/lua/lua_base.h b/lua/lua_base.h
index c7a0770..9a85c49 100644
--- a/lua/lua_base.h
+++ b/lua/lua_base.h
@@ -79,6 +79,16 @@ extern "C"{
 
 typedef void (*lua_output)(const char *fmt, ...);
 
+/*==============================================*
+ *      help system definitions                *
+ *----------------------------------------------*/
+#define MAX_HELP_ENTRIES 32
+
+typedef struct {
+    const char *name;
+    const char *description;
+} lua_help_entry_t;
+
 /*==============================================*
  *      project-wide global variables           *
  *----------------------------------------------*/
@@ -91,6 +101,8 @@ extern lua_output lua_print;
 int lua_init(lua_output _lua_print);
 int lua_repl(char *_pcBuffer, int _iSize, int _iEcho);
 void luaprint_stdout(const char *fmt, ...); 
+void lua_register_help(lua_State *L, const char *name, lua_CFunction func, const char *description);
+void lua_add_help_entry(const char *name, const char *description);
 
 #ifdef __cplusplus
 #if __cplusplus