AP_IOMCU: support oneshot mode

libraries/AP_IOMCU/AP_IOMCU.cpp

@@ -67,7 +67,6 @@ enum ioevents {
     IOEVENT_FORCE_SAFETY_OFF,
     IOEVENT_FORCE_SAFETY_ON,
     IOEVENT_SET_ONESHOT_ON,
-    IOEVENT_SET_ONESHOT_OFF,
     IOEVENT_SET_RATES,
     IOEVENT_GET_RCIN,
     IOEVENT_ENABLE_SBUS,
@@ -217,6 +216,13 @@ void AP_IOMCU::thread_main(void)
                 continue;
             }
         }
+
+        if (mask & EVENT_MASK(IOEVENT_SET_ONESHOT_ON)) {
+            if (!modify_register(PAGE_SETUP, PAGE_REG_SETUP_FEATURES, 0, P_SETUP_FEATURES_ONESHOT)) {
+                event_failed(IOEVENT_SET_ONESHOT_ON);
+                continue;
+            }
+        }
         
         // check for regular timed events
         uint32_t now = AP_HAL::millis();
@@ -548,4 +554,10 @@ void AP_IOMCU::set_default_rate(uint16_t rate_hz)
     trigger_event(IOEVENT_SET_DEFAULT_RATE);
 }
 
+// setup for oneshot mode
+void AP_IOMCU::set_oneshot_mode(void)
+{
+    trigger_event(IOEVENT_SET_ONESHOT_ON);
+}
+
 #endif // HAL_WITH_IO_MCU

libraries/AP_IOMCU/AP_IOMCU.h

@@ -69,7 +69,10 @@ public:
 
     // set default output rate
     void set_default_rate(uint16_t rate_hz);
-    
+
+    // set to oneshot mode
+    void set_oneshot_mode(void);
+
 private:
     AP_HAL::UARTDriver &uart;