Finding input events in MSFS2024
Input events are the way to interact with Microsoft Flight Simulator 2024 from apps like MobiFlight. Also referred to as Bvars, they provide a defined way to trigger every cockpit interaction.
Input events for Microsoft Flight Simulator 2024 are documented in HubHop under each aircraft with (2024) appended to the end. For example, Cessna 172 input events are under the C172 (2024) aircraft.
The following steps illustrate how to find the input event for the parking brake in a Cessna 172 for use with a toggle switch.
Enable developer mode
In Microsoft Flight Simulator 2024 settings, select the Advanced Options section, then enable the Developer Mode option.
Spawn the plane
Use Free Flight mode to spawn the Cessna 172 at an airport.
Open the behaviors window
From the Tools menu, select Behaviors.
When the behaviors window opens it will look like this:
Find the input event
Aircraft often have hundreds of input events, sometimes with names that aren’t clear, making it challenging to find the correct one. A simple way to quickly locate the correct event is to look it up with a keyboard shortcut.
To find the input event for the parking brake, place the mouse cursor over the parking brake handle in the cockpit, then press CTRL + G on the keyboard.
After pressing the keyboard shortcut, the behaviors window will update to show basic information about the parking brake.
Open the input event details
To view the input events associated with the parking brake, click the InputEvents section to expand it.
Once the section is expanded, click the LANDING_GEAR_PARKINGBRAKE button to open the InputEvents tab with all the events associated with the parking brake handle.
Expand the input events tab
By default, the InputEvents tab hides the important information in a collapsed section. To view all the input events associated with the parking brake, click the LANDING_GEAR_PARKINGBRAKE header to expand the collapsed information.
Identify the correct input event
Controls in Microsoft Flight Simulator have multiple input events, even for simple controls like a parking brake.
The Bindings section lists the input events used with MobiFlight. In this example, there are six different events shown:
- LANDING_GEAR_PARKINGBRAKE_Inc
- LANDING_GEAR_PARKINGBRAKE_Dec
- LANDING_GEAR_PARKINGBRAKE_Set
- PARKING_BRAKES
- PARKING_BRAKE_SET
- LANDING_GEAR_PARKINGBRAKE_TOGGLE
The suffix at the end of each event is a good indicator of its intended use. Events ending in Inc and Dec are useful when mapping controls to a rotary encoder. Events ending in TOGGLE are useful when mapping controls to a push button. Events ending in Set are useful when mapping controls to a toggle switch. While not available for the parking brake, ON and OFF events are common as well.
Testing the LANDING_GEAR_PARKINGBRAKE_Set event
Since the parking brake will get mapped to a toggle switch, with a specific on and off position, the LANDING_GEAR_PARKINGBRAKE_Set event is likely the correct one to use with MobiFlight.
To test it, expand the event to see the parameters and Execute button.
The event takes a single parameter to set the parking brake state. In most cases, events that turn something on and off use 1 as the parameter to indicate on and 0 to indicate off.
This assumption can be tested by entering a 1 in the parameter box and pressing the Execute button. The parking brake in the simulator should move to the on position. Entering a 0 in the parameter box and pressing the Execute button should move the parking brake to the off position.
Using the event in MobiFlight
With the event tested and working, it can now be converted to the correct format for use in MobiFlight. Copy the event name by right-clicking on it and selecting Copy to Clipboard.
In MobiFlight, create a new input configuration and select the appropriate switch as the device. Set the Action Type for On Press to Microsoft Flight Simulator and check the Show Preset Code box. The preset code box is where the event will go.
The event needs to be converted to RPN format for use as a custom preset. For the On Press event, where the input event gets set to 1, use the following custom code:
1 (>B:LANDING_GEAR_PARKINGBRAKE_Set)
For the On Release event, use the following custom code:
0 (>B:LANDING_GEAR_PARKINGBRAKE_Set)Notice how the event name discovered in the previous steps is wrapped with (>B: and ), and 1 and 0 are used to set and release the parking brake. This pattern applies to any input event that takes a value.
Close the dialog and try it out
Click the OK button to close the dialog.
Make sure the MobiFlight Run button is clicked in the toolbar, then try toggling the parking brake with the switch. The parking brake in the simulator should toggle.