diff --git a/libraries/AP_HAL/Scheduler.h b/libraries/AP_HAL/Scheduler.h
index 5f010e6a54..883263336d 100644
--- a/libraries/AP_HAL/Scheduler.h
+++ b/libraries/AP_HAL/Scheduler.h
@@ -17,14 +17,13 @@ public:
     virtual void     delay_microseconds(uint16_t us) = 0;
     virtual void     register_delay_callback(AP_HAL::Proc,
                         uint16_t min_time_ms) = 0;
+
     virtual void     register_timer_process(AP_HAL::TimedProc) = 0;
-    virtual void     register_timer_failsafe(AP_HAL::TimedProc,
-                        uint32_t period_us) = 0;
     virtual void     suspend_timer_procs() = 0;
     virtual void     resume_timer_procs() = 0;
-
-    virtual void     begin_atomic() = 0;
-    virtual void     end_atomic() = 0;
+    
+    virtual void     register_timer_failsafe(AP_HAL::TimedProc,
+                        uint32_t period_us) = 0;
 
     virtual void     panic(const prog_char_t *errormsg) = 0;
     virtual void     reboot() = 0;