Saturday

Build Your Own Arcade Machine From an Old Computer

Did you find yourself feeding quarters to arcade machines in the '80s and '90s? Do you have any old computers -- or even computer parts -- sitting around taking up space? Do you want to relive those great arcade moments in the comfort of your own home?


It's all possible thanks to emulators. Emulators are pieces of software designed to imitate a particular arrangement of hardware and software. There are emulators for just about any sort of hardware or software you can imagine. But when it comes to arcade games, one emulator reigns supreme: the Multiple Arcade Machine Emulator, or MAME.

The purpose of MAME is to preserve old arcade games. Most arcade games were hardwired into processor chips. However, there were a few games like Dragon's Lair and Space Ace that ran on laserdiscs. You might also run into an arcade game that relies on some other form of storage device, but for the most part, the code that makes your favorite arcade games tick exists on physical chips attached directly to a circuit board inside the machine.

The MAME software emulates that hardware, including the arcade machine's memory, processors or central processing unit (CPU) and input/output (I/O) spaces. When paired with an arcade game ROM (an acronym for read-only memory) and perhaps a selection of sound samples, MAME can imitate that game. The MAME program supports thousands of ROMs. But while MAME is free and easily available, you won't find any ROMs with it when you download a copy. That's because most arcade games -- even those made by companies that have since closed -- are protected by copyright. Unless you own a copy of the physical hardware for a particular arcade game, it's against the law to download and own a ROM.

But let's assume you have a big pile of arcade game chips sitting in a box at home. You've purchased each and every one legitimately, but you lack the hardware to run them or the games themselves have deteriorated. In that case, it's perfectly legal for you to seek out the ROMs for the games you own and download them. Lots of sites on the Web host ROMs -- they aren't hard to find.

Of course you could just run the emulator and ROMs on your computer and play games like that. But what if you want the real arcade experience? You'll need to put in some work and be skilled in sketching, carpentry, wiring and coding. But in the end, you could own an arcade machine capable of playing practically any arcade game ever made.

Choosing an Arcade Monitor and Computer

According to the MAME Web site, the minimum requirements for running MAME on a computer are:The first thing you need to keep in mind is that the designers of MAME wanted to create a way to preserve video games -- the ability to play the games is simply a byproduct. That means that while the goal of the emulator is to recreate the arcade machine hardware's behavior as faithfully as possible, it doesn't always translate into a playable game. Programmers are always working to improve MAME, and older versions may not support all ROMs. Some games may run but will be extremely slow. You should test your ROMs with the version of MAME you prefer before jumping into an arcade machine project.
  • Any MMX-capable AMD or Intel processor
  • Windows 98 or later
  • DirectX 5.0 or later
  • A DirectDraw or Direct3D capable graphics card
  • Any DirectSound capable sound card
Most modern PCs blow the doors off of these minimal requirements. The more powerful a computer is, the better it will be at handling the processing requirements of MAME. Computers that have a graphics card with a graphics processing unit (GPU) may fare better than machines with basic graphics cards. Because MAME is attempting to reproduce the behavior of hardware, it requires a lot of processing power. Because of this, some games may run poorly no matter how fast your machine is.

There are other versions of MAME called ports that will run on machines with a Mac or Linux-based operating system. If you download the basic PC version of MAME, you'll see that it's a command-line system. That means you must type in commands to change settings and run ROMs. If you prefer, you can download a MAME frontend that incorporates a graphical user interface (GUI). A good GUI will eliminate the need to incorporate a keyboard into the final arcade machine.

You'll also need a monitor for your game. Some MAME enthusiasts prefer cathode ray tube (CRT) television sets to computer monitors. They argue that computer monitors provide too sharp a picture and detract from the real arcade experience. If you choose a television, make sure your computer and TV can connect with the right cables. A CRT with an S-Video port and a computer containing a graphics card with its own S-Video port works well, but there are other options. 

Deciding on Your Arcade Controllers

What kind of games do you want to play? Arcade games like Centipede work best with a trackball. The classic game Tempest used a dial-like rotary controller. Several driving games used a combination of a steering wheel and pedals for the gas and brake. And of course, hundreds of games had a combination of joysticks and buttons.

MAME supports many different ­controls. You could install standard game controller ports on the computer you'll be using and hook up standard computer joysticks, steering wheels or gamepads. You can even use game controllers that connect to your computer via USB. MAME doesn't automatically enable the controller function -- you'll have to turn it on either by a line command or through a GUI.

These controllers should work with most games, but they don't necessarily reproduce the feeling of a real arcade machine. For that, you need to go out and buy actual arcade controllers and buttons. Some vendors sell prefabricated game control panels that you can purchase and incorporate into a cabinet. A prefabricated control panel will cost more than the sum of its individual components, but it will save you time when it comes to wiring and encoding your controls. Still, many enthusiasts like the freedom they have when they buy each component separately and design their own game control panels.

Some MAME arcade machine fabricators like to include multiple control devices on a single machine. MAME enthusiast Jeff McClain built what he calls the Ultimate MAME Cabinet and included four joysticks, a spinner control, a trackball, a light gun and more than a dozen buttons in a custom-built cabinet [source: Ultimate MAME Cabinet]. Many vendors sell arcade machine controls -- you should be able to find most standard controls without too much trouble. If you want something specific -- such as the Star Wars flying yoke or Spy Hunter's custom steering wheel -- that might require a bit more effort to seek out.


Using Arcade Controls

That's the secret: you can replace these switches with other switches. Most arcade controls are actually just switches. Arcade joysticks are switches that move two, four or eight directions. A button is a simple on/off switch. There are two main kinds of switches for arcade controllers: leaf spring switches and microswitches. Many arcade enthusiasts say that the leaf spring design provides a better feel when playing a game. Microswitches tend to have a clicky, stiffer feel. But leaf spring switches are hard to find and require maintenance more often than microswitches. If you decide to go with leaf springs, be prepared to search around for parts.If you do decide to use real arcade controls, you'll face another choice: how do you connect these devices to your computer? There are a few different methods you could try, but perhaps the most popular and versatile method is to use a keyboard encoder (also known as a key encoder). By default, MAME maps each arcade control to a specific key on the keyboard. Keyboards contain a circuit board. Wires connect each key to a specific connector on the circuit board. When you press a key, it completes a circuit and sends a signal to the circuit board. The computer interprets the action as a keystroke. Each key is really a switch.

If you map each direction of the joystick to a different key on the circuit board, you can program MAME to accept the input . Some key encoder boards can accept input from trackballs and spinners, and some MAME arcade machine enthusiasts have built special encoders that they offer for sale.

There are other ways to wire controls to a computer, too. You might be able to pull out the circuit board from a computer gamepad, wire your controls to the circuit board and map everything out to the computer. But most MAME enthusiasts prefer key encoders because they can handle more inputs.

Not all key encoders are created equal so it's wise to do some research before purchasing one. Watch out for effects like ghosting. Ghosting is when a key encoder sends a signal for a specific keystroke even if you didn't push that particular key. It usually happens when the key encoder receives several signals in a very short burst. This can be annoying when you're typing on a computer. But when you're playing an arcade game, it could cause you to make an unintentional suicidal jump or accidentally shoot that princess you've been trying to save for 18 levels.

Arcade Lights and Sound

No arcade machine is complete without a lit display on the top and a sound system worthy of transmitting the bloops and bleeps of classic arcade games. While you really want the graphics and controls to feel authentic, it's the little touches that help complete the feeling of playing on an actual arcade machine.

For the arcade machine's overhead display, you'll need a light source, some plexiglass and a marquee, which is a translucent material with artwork on it. If you don't have the ability to make your own marquee, you can buy one. Several Web sites sell marquees for MAME machines and can cut the material to whatever size you need. Many even offer designs that incorporate the MAME acronym into the artwork. Some also offer graphics you can mount on the side of your arcade cabinet.

Fluorescent light fixtures are good light sources. They don't generate a lot of heat, the bulbs last longer than incandescent lights and you can find the bulbs and fixtures in different lengths.

You'll need to sandwich the marquee between the sheets of Plexiglas to protect the artwork. Install the fluorescent light in the top of the cabinet and make sure the light source is aimed toward the front of the cabinet where the marquee will be. Test it out to make sure you've got the effect you wanted -- you can make tweaks by either moving the light source closer to or further from the marquee or by using a different bulb wattage.

As for sound, that depends on what you're using as a monitor. If you're using a television set, the set's speakers should work fine. But if you've chosen to go with a computer monitor, you'll need to install a sound card in your computer, and mount some speakers inside the cabinet. You'll also need to make sure the sound card is compatible with the version of MAME you'll be using. It's a good idea to shop around for speakers since you'll want something that can recreate the entire range of sounds you'd find in arcade games. You may also want to mount the speakers near the marquee if you want to avoid a muffled sound.


Arcade Machine Cabinets

To build a cabinet, you really need to plan ahead. You have to take into consideration the computer and monitor (or television set) you're using, the controls you'll install and even where you plan to put the machine in your home. Arcade machines are pretty large, and if you want an all-in-one arcade game yours will be larger than the average classic arcade machine.You can find arcade machine cabinets on sale at various warehouses, auctions and Web sites, but they tend to be costly. Buying cabinet parts is less expensive but still a significant cost. On top of the purchase price you may have to deal with shipping charges and there's no guarantee that your MAME setup will fit inside a prefabricated cabinet. That's why many enthusiasts choose to build their own arcade cabinets from scratch.

If you're designing your own cabinet, you're really only limited by the equipment you'll be using, the floor space you have available in your home, your budget and your imagination. Enthusiasts have built MAME machines that look like classic arcade cabinets, oversized machines with multiple control systems, cocktail table systems and even cockpit machines complete with a seat inside. The smallest of these systems is the cocktail table, which places the face of the monitor up and has controls on either end of the table.

You can find plans for arcade cabinets all over the Web. There are designs for just about any configuration you could want. And nothing is stopping you from designing your own version!

To build a cabinet, you'll need fiberboard or a similar material for the body. You'll also need wood glue, screws, bolts and brackets to hold it together. You'll require tools such as a drill, a table saw, a jigsaw, a screwdriver and a rubber mallet. Optional hardware could include hinges for a door in the front, a door clasp and a power switch.

You'll also need to plot out your game control panel carefully. You need to make sure you have enough room for the wiring on the underside of the panel, particularly if you're trying to combine several different control systems into one setup. Some enthusiasts prefer to create interchangeable panels designed specifically for different kinds of games. But that would mean you'd need a place to store the control panels you're not currently using.

It's probably best to find a set of plans on the Web and follow those for your first project. You can experiment later.

Wiring the Controls


We've reached what is possibly the most challenging part of building your arcade machine. Wiring takes time, patience and skill. There's also an element of trial and error involved, particularly if you're not accustomed to handling wires. Depending on the method you've chosen to connect your controls to your computer, you may need the following:
  • Wires in the 22- to 28-gauge range (.326 to .081 square millimeters) for the controls
  • 18-gauge wire (.821 square millimeters) for wiring that will connect to AC power or ground
  • Wire cutters, strippers and crimpers
  • Soldering iron and solder
You'll have to connect each control to the key encoder by crimping or soldering the wires to the appropriate connectors. You can link the ground wire connectors in series to a common ground. The key encoder (or other interface) should connect to your computer using a connecter and a standard cable -- usually a keyboard cable. You can run the MAME program to test your controls once you've wired them to the encoder. It's a slow process -- you have to determine which keystrokes your controls are simulating and then map those keystrokes to the correct control settings in MAME.

Let's say you've wired up an arcade control system to an encoder. You push the left joystick up and look to see with which keystroke that action corresponds. You notice that it corresponds with T. You would need to tell MAME that the T keystroke should map to player one pushing up on the joystick. You'll need to repeat this procedure over and over again to map every action for your system.

You'll also need to install a power strip or junction box inside your machine if you want to limit your cabinet to just one exterior cable. You can plug your various components into the strip or junction box. You may even want to install an exterior power switch to activate your computer and other electronics so that you don't have to open the cabinet to switch on your machine.

Wiring can become a complicated task, particularly if you want to maximize the number of inputs. We recommend you look at some of the following Web sites to learn more about wiring and interfaces:
It's a lot of work, but for the dedicated hobbyist there's no better payoff than building a working MAME machine. In the end, you'll have a full arcade stored in a single cabinet. Game on!