diff --git a/bsp/samd21/applications/application.c b/bsp/samd21/applications/application.c
index 186ee8ac4a..d89bdd2a60 100644
--- a/bsp/samd21/applications/application.c
+++ b/bsp/samd21/applications/application.c
@@ -83,6 +83,13 @@ void rt_init_thread_entry(void* parameter)
     rt_device_t dev;
 
     rt_kprintf("SYSTEM running at %uhz\n", SystemCoreClock);
+
+#ifdef RT_USING_FINSH
+    /* init finsh */
+    finsh_system_init();
+    finsh_set_device("uart1");
+#endif
+
     LED_Init();
     configure_extint_channel();
     configure_extint_callbacks();
@@ -90,7 +97,7 @@ void rt_init_thread_entry(void* parameter)
 #ifndef TEST_UART_RX
 
     sleep_timer_init();
-	// sleep_timer_start(1500);
+    // sleep_timer_start(1500);
 
     while (1)
     {
diff --git a/bsp/samd21/applications/startup.c b/bsp/samd21/applications/startup.c
index 8717d95dca..b8c2c83d0d 100644
--- a/bsp/samd21/applications/startup.c
+++ b/bsp/samd21/applications/startup.c
@@ -49,11 +49,11 @@ extern int __bss_end;
 *******************************************************************************/
 void assert_failed(uint8_t* file, uint32_t line)
 {
-	rt_kprintf("\n\r Wrong parameter value detected on\r\n");
-	rt_kprintf("       file  %s\r\n", file);
-	rt_kprintf("       line  %d\r\n", line);
+    rt_kprintf("\n\r Wrong parameter value detected on\r\n");
+    rt_kprintf("       file  %s\r\n", file);
+    rt_kprintf("       line  %d\r\n", line);
 
-	while (1) ;
+    while (1) ;
 }
 #endif
 
@@ -62,66 +62,60 @@ void assert_failed(uint8_t* file, uint32_t line)
  */
 void rtthread_startup(void)
 {
-	/* init board */
-	rt_board_init();
+    /* init board */
+    rt_board_init();
 
-	/* show version */
-	rt_show_version();
+    /* show version */
+    rt_show_version();
 
-	/* init tick */
-	rt_system_tick_init();
+    /* init tick */
+    rt_system_tick_init();
 
-	/* init kernel object */
-	rt_system_object_init();
+    /* init kernel object */
+    rt_system_object_init();
 
-	/* init timer system */
-	rt_system_timer_init();
+    /* init timer system */
+    rt_system_timer_init();
 
 #ifdef RT_USING_HEAP
-	#ifdef __CC_ARM
-		rt_system_heap_init((void*)&Image$$RW_IRAM1$$ZI$$Limit, (void*)CHIP_SRAM_END);
-	#elif __ICCARM__
-	    rt_system_heap_init(__segment_end("HEAP"), (void*)CHIP_SRAM_END);
-	#else
-		/* init memory system */
-		rt_system_heap_init((void*)&__bss_end, (void*)CHIP_SRAM_END);
-	#endif
+    #ifdef __CC_ARM
+        rt_system_heap_init((void*)&Image$$RW_IRAM1$$ZI$$Limit, (void*)CHIP_SRAM_END);
+    #elif __ICCARM__
+        rt_system_heap_init(__segment_end("HEAP"), (void*)CHIP_SRAM_END);
+    #else
+        /* init memory system */
+        rt_system_heap_init((void*)&__bss_end, (void*)CHIP_SRAM_END);
+    #endif
 #endif
 
-	/* init scheduler system */
-	rt_system_scheduler_init();
+    /* init scheduler system */
+    rt_system_scheduler_init();
 
-	/* init application */
-	rt_application_init();
-
-#ifdef RT_USING_FINSH
-	/* init finsh */
-	finsh_system_init();
-	finsh_set_device("uart1");
-#endif
+    /* init application */
+    rt_application_init();
 
     /* init timer thread */
     rt_system_timer_thread_init();
 
-	/* init idle thread */
-	rt_thread_idle_init();
+    /* init idle thread */
+    rt_thread_idle_init();
 
-	/* start scheduler */
-	rt_system_scheduler_start();
+    /* start scheduler */
+    rt_system_scheduler_start();
 
-	/* never reach here */
-	return ;
+    /* never reach here */
+    return ;
 }
 
 int main(void)
 {
-	/* disable interrupt first */
-	rt_hw_interrupt_disable();
+    /* disable interrupt first */
+    rt_hw_interrupt_disable();
 
-	/* startup RT-Thread RTOS */
-	rtthread_startup();
+    /* startup RT-Thread RTOS */
+    rtthread_startup();
 
-	return 0;
+    return 0;
 }
 
 /*@}*/