diff --git a/sdk/components/step_motor_ctrl_module/step_motor_ctrl_module.cpp b/sdk/components/step_motor_ctrl_module/step_motor_ctrl_module.cpp
index ca4682e..853e000 100644
--- a/sdk/components/step_motor_ctrl_module/step_motor_ctrl_module.cpp
+++ b/sdk/components/step_motor_ctrl_module/step_motor_ctrl_module.cpp
@@ -480,8 +480,8 @@ int32_t StepMotorCtrlModule::step_motor_easy_reciprocating_motion(int32_t startp
   int32_t ecode = check_befor_run();
   if (ecode != 0) return ecode;
   
-  int32_t x_startpos;
-  int32_t x_endpos;
+  int32_t x_startpos = startpos;
+  int32_t x_endpos = endpos;
   int32_t x_beginpos;
   getnowpos(x_beginpos);
 
diff --git a/usrc/project_configs.h b/usrc/project_configs.h
index b206b87..45358da 100644
--- a/usrc/project_configs.h
+++ b/usrc/project_configs.h
@@ -1,5 +1,5 @@
 #pragma once
-#define PC_VERSION           504
+#define PC_VERSION           505
 #define PC_MANUFACTURER      "http://www.iflytop.com/"
 #define PC_PROJECT_NAME      "a8000_subboard"
 #define PC_IFLYTOP_ENABLE_OS 1