diff --git a/easylogger/port/elog_port.c b/easylogger/port/elog_port.c
index 9d476a0..49a7796 100644
--- a/easylogger/port/elog_port.c
+++ b/easylogger/port/elog_port.c
@@ -72,6 +72,24 @@ void elog_port_interrupt_get_nest(void) {
 
 }
 
+/**
+ * output lock in isr context
+ */
+void elog_port_output_lock_isr(void) {
+
+    /* add your code here */
+
+}
+
+/**
+ * output unlock in isr context
+ */
+void elog_port_output_unlock_isr(void) {
+
+    /* add your code here */
+
+}
+
 /**
  * output lock
  */
diff --git a/easylogger/src/elog.c b/easylogger/src/elog.c
index 48f8bb9..8f81bd7 100644
--- a/easylogger/src/elog.c
+++ b/easylogger/src/elog.c
@@ -149,6 +149,8 @@ void (*elog_assert_hook)(const char* expr, const char* func, size_t line);
 
 extern void elog_port_output(const char *log, size_t size);
 extern int elog_port_interrupt_get_nest(void);
+extern void elog_port_output_lock_isr(void);
+extern void elog_port_output_unlock_isr(void);
 extern void elog_port_output_lock(void);
 extern void elog_port_output_unlock(void);
 
@@ -385,6 +387,9 @@ void elog_output_lock(void) {
         } else {
             elog.output_is_locked_before_enable = true;
         }
+    } else {
+        if (elog.output_lock_enabled)
+            elog_port_output_lock_isr();
     }
 }
 
@@ -399,6 +404,9 @@ void elog_output_unlock(void) {
         } else {
             elog.output_is_locked_before_enable = false;
         }
+    } else {
+        if (elog.output_lock_enabled)
+            elog_port_output_unlock_isr();
     }
 }