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Certain keys can be used to change the way MAME behaves while you are playing a game. Other keys can be used to get information about a particular game. The following guide presents the more commonly used keys (according the their default assignment, which you may change at any time in the Input (general) menu of the in-game menu. See Playing MAME for more information on how to reassign inputs.)

[edit] Default keys

Key	Description
Tab	Toggles the display of the MAME menu on and off. See the MAME menu below for more information.
~	Toggles the On Screen Display. Use the up and down arrow keys to select which parameter to modify (global volume, mixing level, gamma correction etc.) Use the left and right to arrow keys to change modify the value. Some parameters adjust with finer or coarser control if you hold down the Ctrl or Shift keys while pressing ←/→. Use Enter key to reset a value to its default.
P	Pause the game. The screen will darken by a certain amount to indicated that you are paused.
Shift + P	While paused, press Shift + P to advance the screen of the game by one frame.
F1	Toggles the display of crosshairs on and off. This is only for lightgun games that make use of crosshairs to indicate where your lightgun is pointing.
F2	This typically toggles the Service Mode switch from off to on, and then from on to off. Service Mode is where many arcade operators could test the controls and display of a game cabinet, as well as adjust certain settings that were not made available through dip switches. If you wish to enter service mode, you must press F2 once, and then press F3 to reset the machine so that it actually enters the service mode. Likewise, to leave service mode, you must press F2 once more and press F3 to return to the game. Not all games have a service mode; if not, check the Dip Switches option under the Tab menu. See The MAME menu for more.
F3	Resets the game. When you press this button, most games will pause momentarily and then behave as though the machine was just turned on, cycling through a display test if the game possesses one.
F4	Displays the graphics mode. See F4 below for more information.
F6	Toggles cheat mode on and off if cheats are enabled.
F7	Load a save state. You will be requested to press a key to determine which save state you wish to load. Note that the save state feature is not supported for a large number of drivers. If support is not enabled for a given driver, you will receive a warning when attempting to save or load.
Shift + F7	Create a save state. Requires an additional keypress to identify the state, similar to the load option above. Saves can be bound to both letters and numbers.
F8	Decreases the frame skip by one. Use this if you feel that the game animation is stuttering too much. This may introduce slow down as a result.
F9	Increase the frame skip by one. Use this if you feel that the game animation is too slow. This may introduce stuttering to the animation.
F10	Toggles the speed throttling on and off. Assuming you have Throttle checked on the Display page of the Game Properties dialog, pressing F10 will remove the throttle and allow the game to run as fast as possible. To return to normal speed, you must press F10 again.
F11	Pressing this causes a small window to appear in the upper right corner of your screen to presents certain information about how many screens have been rendered since the game started playing, what frameskip MAME is using (0 for none,) and what percentage of the full frame rate the game is playing at.
F12	Press F12 to save a screen capture of your game in progress. All saved screen captures end up in the snap folder that lives in the MAME directory. Most MAME front-ends use the contents of this directory to access screenshots and show you what the game looks like before you choose to play it.
Insert	This works in a similar way to F10, except that the throttle only lasts for as long as you hold Insert down. As soon as you release Insert, the game returns to normal speed. You can use this to skip past particular long or boring segments of a game.
Esc	Press this to exit the emulator. There is no confirmation dialog.

[edit] F4

Shows the game palette, decoded GFX, and any tilemaps. Use Enter key to switch between the three modes (palette, graphics, and tilemaps). Press F4 again to turn off the display. The key controls in each mode vary slightly:

• Palette/colortable mode:

Keys	Description
[ ]	switch between palette and colortable modes
↑/↓	scroll up/down one line at a time
Pg Up/Pg Dn	scroll up/down one page at a time
Home/End	move to top/bottom of list
-/+	increase/decrease the number of colors per row
Enter	switch to graphics viewer

• Graphics mode:

Keys	Description
[ ]	switch between different graphics sets
↑/↓	scroll up/down one line at a time
Pg Up/Pg Dn	scroll up/down one page at a time
Home/End	move to top/bottom of list
←/→	change color displayed
R	rotate tiles 90 degrees clockwise
-/+	increase/decrease the number of tiles per row
Enter	switch to tilemap viewer

• Tilemap mode:

Keys	Description
[ ]	switch between different tilemaps
↑/↓/←/→	scroll 8 pixels at a time
Shift + ↑/↓/←/→	scroll 1 pixel at a time
Ctrl + ↑/↓/←/→	scroll 64 pixels at a time
R	rotate tilemap view 90 degrees clockwise
-/+	increase/decrease the zoom factor
Enter	switch to palette/colortable mode

Note: Not all games have decoded graphics and/or tilemaps.

[edit] The MAME menu

Once you have selected and started a game in MAME, you bring up the in-game MAME menu by pressing Tab. This menu should look something like the picture on the right. To learn more about Input (general) and Input (this Game), please see Playing MAME. The rest of the selections will be explained here.

• Dip Switches: Selecting this option drills down to another menu where you are given the ability to toggle the dip switches that are found on the real arcade cabinet. Dip switches were small and (sometimes poorly) hidden switches on the cabinet that allowed an arcade operator to change several features of the games behavior, such as how many quarters were needed to earn one credit, how many lives a player started with, how many points were needed to gain an extra life, and the overall difficulty of the game. Each game has their own set of dip switches and MAME will most likely inform you of the function of each switch, provided that function is known. Note that if you make changes to any of the switches, you will most likely need to reset the game (F3) first before the changes take place. Some games place these settings in the service mode (press F2 to access service mode).
• Bookkeeping Info: Selecting this option brings up another window that informs you of the amount of time in minutes and seconds that a game has been running for in MAME. It also informs you of how many quarters have been "entered" in to the machine over the lifetime of the ROM's use in MAME.
• Game Information: Selecting this option brings up the same window that ordinarily appears if you do not check the Skip game info option in the Misc. page of the Game Properties dialog. This information includes: The name of the game, the year it was made, the company that made it, the list of CPUs used by the game, the list of sound processors used by the games, and the native screen resolution and refresh rate.
• Video Options: Selecting this option brings up another menu that allows you to make on the fly changes to the rendering configuration that MAME uses. You can change the view ration, rotate the view, or make changes to the artwork configuration that you chose (which affects Backdrops, Overlays, and Bezels, as well as whether to crop them or not.) For more information about these choices please refer to the Configuration page of this guide.
• Reset Game: This has the same effect as pressing F3, described above.
• Return to Game: Selecting this removes the menu from the screen and returns input to control of the game. The same thing can be accomplished by pressing Tab or Esc anywhere on this menu.