diff --git a/src/Devices/AtcDimetronic.cs b/src/Devices/AtcDimetronic.cs
index aa4ad61..f5490a2 100644
--- a/src/Devices/AtcDimetronic.cs
+++ b/src/Devices/AtcDimetronic.cs
@@ -57,6 +57,7 @@ namespace OpenbveFcmbTrainPlugin
         private enum AtoStates
         {
             Inactive,
+            Alarm,
             AwaitingStartup,
             IncreaseSpeed,
             MaintainSpeed,
@@ -70,6 +71,18 @@ namespace OpenbveFcmbTrainPlugin
         /// <summary>Whether ATO knows the precise position of the train or not.</summary>
         private bool AtoPositionKnown;
 
+        /// <summary>The distance travelled in ATO mode since the latest startup.</summary>
+        private double AtoStartupPosition;
+
+        /// <summary>The power notch to be applied by ATO.</summary>
+        private int AtoPowerNotch;
+
+        /// <summary>The brake notch to be applied by ATO.</summary>
+        private int AtoBrakeNotch;
+
+        /// <summary>Whether ATO is available or not on the train.</summary>
+        private readonly bool AtoAvailable;
+
         /// <summary>The current position of the train.</summary>
         private double TrainLocation;
 
@@ -94,9 +107,6 @@ namespace OpenbveFcmbTrainPlugin
         /// <summary>The distance after which the rollforward protection is triggered.</summary>
         private readonly double RollforwardDistance;
 
-        /// <summary>Whether ATO is available or not on the train.</summary>
-        private readonly bool AtoAvailable;
-
         /// <summary>The index of the alarm sound.</summary>
         private readonly int AlarmSoundIndex;
 
@@ -241,15 +251,15 @@ namespace OpenbveFcmbTrainPlugin
                 RollforwardLocation = train.State.Location;
             }
 
-            // Update train location
-            TrainLocation = train.State.Location;
-
-            // If ATO is not the current mode, it should be in inactive state
+            // Reset ATO status outside ATO mode
             if (DeviceState != DeviceStates.ATO)
             {
-                AtoState = AtoStates.Inactive;
+                AtoState = AtoState == AtoStates.Alarm ? AtoStates.Alarm : AtoStates.Inactive;
             }
 
+            // Update train location
+            TrainLocation = train.State.Location;
+
             double speed = train.State.Speed.KilometersPerHour;
             bool stopped = speed < 0.05;
 
@@ -285,7 +295,7 @@ namespace OpenbveFcmbTrainPlugin
                 }
 
                 // Rollforward protection
-                if (train.PhysicalHandles.BrakeNotch > 0 || train.PhysicalHandles.PowerNotch > 0)
+                if (train.PhysicalHandles.BrakeNotch > 0 || train.PhysicalHandles.PowerNotch > 0 || RequestedBrakeNotch > 0 || RequestedPowerNotch > 0)
                 {
                     // The train has a power/brake notch applied, movement is expected
                     RollforwardTrigger = false;
@@ -339,6 +349,9 @@ namespace OpenbveFcmbTrainPlugin
                     train.VigilanceOverride = false;
                     // Release control of the brakes and power
                     AtcControlState = AtcControlStates.Released;
+                    // Reset ATO data
+                    AtoPositionKnown = false;
+                    AtoState = AtoStates.Inactive;
                     break;
                 // ATC device is initialized and a driving mode is required
                 case DeviceStates.NoMode:
@@ -462,6 +475,10 @@ namespace OpenbveFcmbTrainPlugin
                         // ATO start button
                         if (!OpenbveFcmbTrainPlugin.KeysPressed[(int)key])
                         {
+                            if (AtoState == AtoStates.AwaitingStartup)
+                            {
+                                AtoState = AtoStates.IncreaseSpeed;
+                            }
                         }
                         break;
                     case VirtualKeys.B1:
@@ -683,12 +700,14 @@ namespace OpenbveFcmbTrainPlugin
             Speed target = CurrentSpeedCode.TargetLimit;
             double distance = CurrentSpeedCode.TargetPosition - TrainLocation;
 
+            // Calculate notches according to state
             switch (AtoState)
             {
                 case AtoStates.Inactive:
                     // Keep train still
-                    RequestedPowerNotch = 0;
-                    RequestedBrakeNotch = train.Specs.BrakeNotches + 1;
+                    AtoPowerNotch = 0;
+                    AtoBrakeNotch = train.Specs.BrakeNotches + 1;
+                    AtoStartupPosition = TrainLocation;
 
                     // If the train is stopped, doors are closed and signal is clear, change to startup state
                     if (stopped && train.DoorState == DoorStates.None && target.KilometersPerHour > 0)
@@ -696,6 +715,32 @@ namespace OpenbveFcmbTrainPlugin
                         AtoState = AtoStates.AwaitingStartup;
                     }
                     break;
+                case AtoStates.Alarm:
+                case AtoStates.AwaitingStartup:
+                    // Keep train still
+                    AtoPowerNotch = 0;
+                    AtoBrakeNotch = train.Specs.BrakeNotches + 1;
+                    AtoStartupPosition = TrainLocation;
+                    break;
+                case AtoStates.IncreaseSpeed:
+                    AtoBrakeNotch = 0;
+                    if (train.Acceleration < 0.2 && AtoPowerNotch < train.Specs.PowerNotches)
+                    {
+                        // TODO: Add delay
+                        AtoPowerNotch++;
+                    }
+                    break;
+            }
+
+            // Apply notches
+            RequestedPowerNotch = AtoPowerNotch;
+            RequestedBrakeNotch = AtoBrakeNotch;
+
+            // ATO is driving but does not know the position of the train, unselect driving mode and set alarm state
+            if (TrainLocation - AtoStartupPosition > 400 && !AtoPositionKnown)
+            {
+                AtoState = AtoStates.Alarm;
+                DeviceState = DeviceStates.NoMode;
             }
         }
     }