diff --git a/Hyt2/GD32F4xx_Firmware_Library/SYSTICK/gd32f4xx_it.c b/Hyt2/GD32F4xx_Firmware_Library/SYSTICK/gd32f4xx_it.c
index f01724b..2d8d165 100644
--- a/Hyt2/GD32F4xx_Firmware_Library/SYSTICK/gd32f4xx_it.c
+++ b/Hyt2/GD32F4xx_Firmware_Library/SYSTICK/gd32f4xx_it.c
@@ -299,7 +299,7 @@ void EXTI10_15_IRQHandler(void)
       exti_init(EXTI_12, EXTI_INTERRUPT, EXTI_TRIG_FALLING);//下降沿中断 
       timer_disable(TIMER7);//失能定时器
       timer_counter_value_config(TIMER7, 0u);
-      ptz_vert_timer_start(20000); 
+      ptz_vert_timer_start(4000); 
       g_dcStepVert = 1;
     }
     /*function end*/