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Nintendo 64:

Nintendo is a company whose name is always associated with video gaming. Chances are that you have played, or at least seen, one of the three home video game consoles the company has created, not to mention the enormously popular hand-held game system, the Gameboy. The Nintendo 64 (N64), was a technical tour de force when it was introduced, and compared admirably to other consoles on the market. As you read, you will learn how the N64 was developed, what's inside, how the controller works and how it all works together. You will also learn about the game cartridges and how they differ from CD-based games.

History:

Just as Atari ushered in the dawn of the home video game, Nintendo is largely considered to be the company that revolutionized the industry with the introduction of the Nintendo Entertainment System (NES) in 1985. An 8-bit system based on the 6502 processor and some custom chips, the NES came together with Super Mario Brothers; this inclusion of an accurate home version of one of the most popular arcade games at the time turned out to be pure genius. Sales of the NES were phenomenal. This established Nintendo as the dominant home video game manufacturer until the late '90s, when it was eclipsed by the Sony PlayStation.

In 1989, Nintendo introduced a new 16-bit system dubbed the Super Nintendo Entertainment System (SNES). Within a couple of years, rivals had introduced 32-bit systems that surpassed the capabilities of the SNES. So, Nintendo announced an agreement with Silicon Graphics Incorporated (SGI) to develop a new 64-bit video game system, code-named Project Reality. Although SGI had never designed video game hardware before, the company was regarded as one of the leaders in computer graphics technology.

After several years of development, the system was finally released in 1996 as the Nintendo 64. But the delays and shortage of games during the first year of availability gave the advantage to Sony, who had released the PlayStation over a year earlier. Nintendo faced the same situation again with the Sony PlayStation 2 debuting in 2000, while Nintendo's Gamecube was not due until fall 2001.

The controller is the primary user interface for the N64. With its trident shape, it is probably the most unusual design for a controller on the market. The standard N64 controller has 14 buttons plus an analog joystick. The buttons include:

  • Four buttons arranged as a directional pad on the top left
  • Start button in the top middle
  • Six action buttons on the top right
  • One action button on the front left
  • One action button on the front right
  • One action button in the bottom middle
  • Analog joystick on the top middle

    Although each button can be configured to perform a specific and distinctive action, they all work on the same principle. In essence, each button is a switch that completes a circuit when it is pressed. A small metal disk beneath the button is pushed into contact with two strips of conductive material on the circuit board inside the controller. While the metal disk is in contact, it conducts electricity between the two strips. The controller senses that the circuit is closed and sends that data to the N64. The CPU compares that data with the instructions in the game software for that button, and triggers the appropriate response. There is also a metal disk under each arm of the directional pad. If you're playing a game in which pushing down on the directional pad causes the character to crouch, a similar string of connections is made from the time you push down on the pad to when the character crouches.

    The analog joystick works in a completely different way from the buttons described above. Two wheels are positioned at right angles to each other below the joystick. Whenever the joystick is moved, the two wheels turn slightly. Tiny slots are arranged around the perimeter of each wheel. The wheels are each mounted between an LED (Light Emitting Diode) and a photo cell. Light from the LED, shining through the slots in the wheel on the cell, creates a small amount of current. When the amount of light changes, the level of current changes. By monitoring the output of each photo cell, the N64 can determine the exact angle at which the joystick is being held, and trigger the appropriate response.

    Another feature of the N64 controller is the ability to add options via an expansion slot on the bottom of the controller. A popular option is the Rumble Pak, which provides force feedback. This feature provides a tactile stimulation to certain actions in a game. For example, in a racing game, you might feel a jarring vibration as your car slams into the wall.

    Force feedback is actually accomplished through the use of a very common device, a simple electric motor. The shaft of the motor holds an unbalanced weight. When power is supplied to the motor, it spins the weight. Because the weight is unbalanced, the motor tries to wobble. But since the motor is securely mounted inside the Rumble Pak, the wobble translates into a shuddering vibration of the controller itself.

    You can save games and high scores by using one of the special Flash memory cards. The card is inserted into the slot on the bottom of the N64 controller.

    The N64 controller uses only three wires to connect to the console. There's a ground wire, another wire that supplies +3, 6 volts of power, and a third wire that carries all data. The controller sends the information for each button in sequence, and then receives data back from the console.

    Games:

    The N64 is the only current system that uses cartridges. There are advantages and disadvantages to this approach:

    Advantages

    • Fast load times - Sections of a game are transferred almost instantly from the cartridge's ROM to the system's RAM.
    • Additional performance features - Since the cartridge contains a circuit board that is plugged into the main system, it can contain special hardware-based enhancements that augment the processing power or special effects of the system.
    • Durability - Cartridges are not as easily damaged as CDs, which can be ruined by a simple scratch.

    Disadvantages

    • Small capacity - Cartridges, ranging from about 8 MB to 96 MB, hold significantly less data than CDs (650 MB).
    • Expense - Because of all the hardware, the cost per unit to manufacture cartridges is quite a bit more than to make CDs.
    • Audio - Even though the N64 has near-CD quality sound, it is not utilized to the same degree as in CD-based games because of the enormous amount of storage required.
Sega Dreamcast:

History

An established leader in the arcade, Sega entered the home market nipping at Nintendo’s heels.  Renamed the Sega Master System, the system known as the Mark III in Japan debuted in the United States in 1986. The Sega Master System used an 8-bit CPU, 128K ROM-based operating system and had a 128K of RAM. Games came on two types of cartridges: a large cartridge that could hold a megabit of game code, and a smaller cartridge that held 256 kilobits of game code.

In 1989, Sega introduced the world's first 16-bit home video game system, the Genesis. Based on Motorola's 68000 processor, the system was technically superior to anything else on the market. But the sheer dominance of Nintendo overshadowed the Genesis, when the rival company debuted the Super Nintendo Entertainment System later that same year.

But Sega beat Sony and Nintendo to the punch with a 32-bit system. The Saturn was officially launched on May 11, 1995. Not only was it the first 32-bit system, but it had two 28.8 MHz 32-bit Hitachi SH-2 processors working in parallel! Sega's Saturn was an amazing system with an incredible architecture, but quickly fell behind the other 32-bit system released that year, Sony's PlayStation.

Code-named Katana, the Dreamcast was released in the fall of 1999, the first system to provide a built-in modem and 128-bit graphics.

Like the N64 and the PlayStation, the CPU in the Dreamcast is a RISC processor. RISC stands for reduced instruction set computer, and means that the instructions and computations performed by the processor are simpler and fewer. Also, RISC chips are superscalar -- they can perform multiple instructions simultaneously. This combination of capabilities, performing more instructions simultaneously and completing each instruction faster because it is simpler, allows the CPU to perform better than many chips with a much faster clock speed.

To lower production costs, the graphics processor is combined with circuitry to control the system through a single application specific integrated circuit (ASIC). Simply put, this means that a custom chip is created to manage all of the necessary components that would normally be handled by separate chips. The Dreamcast sound processor is another ASIC; it combines a 45 MHz ARM7 CPU and a Yamaha digital signal processor (DSP). The ARM7 is a 32-bit RISC chip that handles all processing of the compressed adaptive differential pulse code modulation (ADPCM) audio information in real time. ADPCM is used to sample analog information, compress it at a ratio of 4:1 and store it in digital format.

The Dreamcast has several hardware effects that are handled by the PowerVR chip. They include alpha blending, perspective correction and mip mapping.

Alpha blending uses the alpha channel to add transparency effects to an object. This is a special graphics mode used by digital video, animation and video games to achieve certain looks. Essentially, 24 bits are used to define the red, green and blue amounts, 8 bits each, needed to create a specific color. Another 8 bits are used to create a gray-scale mask that acts as a separate layer for representing levels of object transparency. How transparent an object will be is determined by how dark the gray in the alpha channel is. By making an area of the mask dark gray, you can make an object appear to be very transparent; by making it light gray, you can create special fog or water effects.

Mip mapping is a cool process. It is a form of texture mapping in which different sizes of each texture map are made. In essence, the processor replaces the appearance of an object with a more detailed image as you move closer to the object in the game. Let's take a look at how Dreamcast uses these maps in trilinear mip mapping:

  1. The system calculates the distance from your viewpoint to an object in the game.
  2. The system loads the texture maps for the object. Our three maps will be 64x64 (large), 32x32 (medium), and 8x8 (small).
  3. The system determines the exact size that the image map needs to be. Let's say 16x16 for our example here.
  4. Based on the size, it decides which two texture maps to use. For our example, it will choose the medium and small texture maps.
  5. It will then interpolate (average) between the two texture maps, creating a custom texture map that is 16x16, which it then applies it to the object.

    The Dreamcast is the first console that has a built-in 56 Kbps modem. It was added to enable online play over a phone line, allowing users to play games against each other across long distances. In addition to the built-in modem, Sega is working on a cable or DSL external modem. Broadband networks are being developed that will take advantage of such a modem and enable fast online games for the Dreamcast

    Controller:

    As it is with other systems, the controller is the primary user interface for the Dreamcast. The standard Dreamcast controller has 11 buttons plus an analog joystick. The buttons include:

    • four buttons arranged as a directional pad on the top left
    • Start button in the top middle
    • four action buttons on the top right
    • one analog trigger on the front left
    • one analog trigger on the front right
    • analog joystick on the top left

      Although each button can be configured to perform a specific and distinctive action, all of the buttons, except for the two analog triggers and joystick, work on the same principle. In essence, each button is a switch that completes a circuit whenever it is pressed. A small metal disk beneath the button is pushed into contact with two strips of conductive material on the circuit board inside the controller. While the metal disk is in contact, it conducts electricity between the two strips. The controller senses that the circuit is closed and sends that data to the Dreamcast. The CPU compares that data with the instructions in the game software for that button, and triggers the appropriate response. There is also a metal disk under each arm of the directional pad. If you're playing a game in which pushing down on the directional pad causes the character to crouch, a similar string of connections is made from the time you push down on the pad to when the character crouches.

      The analog joystick and triggers work in a completely different way from the buttons described above. The triggers each have a tiny magnet attached to the end of the trigger arm. When the trigger is depressed, the magnet is pushed toward a sensor mounted on the controller's circuit board. Through the process of induction, the magnet creates resistance to the current passing through the sensor. On the bottom of the magnet is a layer of foam padding. Pushing harder on the trigger compresses the padding, which brings the magnet closer to the sensor. The closer the magnet is to the sensor, the more resistance is induced. This variable resistance makes the triggers pressure-sensitive!

      The joystick also uses a magnet, along with four small sensors. The sensors are arranged like a compass, with one at each of the cardinal points (north, south, east, west). The base of the joystick is shaped like a ball, with tiny spokes radiating out. The ball sits in a socket above the sensors. Spikes on the socket fit between the spokes on the ball. This allows for an extraordinary amount of movement without letting the joystick twist out of alignment with the sensors. As the joystick is moved, the magnet in the base moves closer to one or two of the sensors, and farther from the others. The system monitors the changes in induction caused by the magnet's movement to calculate the position of the joystick.

      The controller has two expansion ports where memory cards, tremor packs, Visual Memory System (VMS) devices and other system additions can be inserted.

      A popular option is the tremor pack, which provides force feedback. This feature provides a tactile stimulation to certain actions in a game. For example, in a racing game, you might feel a jarring vibration as your car slams into the wall. Force feedback is actually accomplished through the use of a very common device, a simple electric motor. The shaft of the motor holds an unbalanced weight. When power is supplied to the motor, it spins the weight. Because the weight is unbalanced, the motor tries to wobble. But since the motor is securely mounted inside the tremor pack, the wobble translates into a shuddering vibration of the controller itself.

      While standard memory cards can be used with the Dreamcast, the VMS units are unique to this console. The VMS is actually a tiny Personal Digital Assistant (PDA) that fits into the upper expansion port of the controller.

      About the size of a business card, each VMS unit contains:

      • 8-bit Hitachi CPU
      • 128 K memory (Flash RAM)
      • Monochrome LCD panel, 48 pixels wide by 32 pixels high
      • Two button (watch) batteries, with auto-off function, to provide power
      • One-channel sound

      When the VMS is inserted into a Dreamcast controller, its LCD can be used to perform some unique functions. For example, in a football game, you can select plays without your opponent seeing what they are. In addition to serving as a memory card for the Dreamcast, the VMS can be used as a stand alone device. Small games, as well as traditional PDA functions like a calendar and phone directory, can be downloaded to the VMS and taken with you

      Games:

      While Dreamcast games are similar to CD-ROM, the actual optical disc used is proprietary, and can hold up to 1.2 gigabytes of information. This is a lot of space -- most games use only a fraction of it for the actual game. What can eat up the space are the incredible full motion video intros and intermissions included in most Dreamcast games.

      There is a noticeable delay while the game is loaded from the CD, which you do not get with cartridge-based games. Of course, the trade-off for faster loading is a significantly smaller amount of storage on a cartridge. Most Dreamcast games use a customized version of Microsoft Windows CE as their operating system; but some use Sega's proprietary Dreamcast operating system.

      Dreamcast CDs are just as susceptible to scratches and intense heat as normal CDs. Even more so in fact, since a scratch on a game CD can make it totally unusable.

      The games available for the Dreamcast cover all the categories, and its library of games is increasing rapidly. Game prices range from under $20 for certain preplayed titles to over $75 for some of the hottest new games.

Playstation:

For five years, the Sony PlayStation (PSX) was the dominant video game system. Although challenged by the incredible technical features of the Nintendo 64 and the next generation Sega Dreamcast, the PlayStation was so popular that Sony estimates one out of every four households in the United States has one!

History:

In 1988, Sony entered into an agreement with Nintendo to develop a CD-ROM attachment, known as the Super Disc, for the soon-to-be released Super Nintendo. Due to many contractual and licensing problems, the Super Disc was never released. Instead, a modified version was introduced by Sony in 1991, in a system called the Play Station.

The original Play Station read these Super Discs, special interactive CDs based on technology developed by Sony and Phillips called CD-ROM/XA.  This extension of the CD-ROM format allowed audio, video and computer data to be accessed simultaneously by the processor. The Play Station also read audio CDs, and had a cartridge port for accepting Super Nintendo game cartridges. The Play Station was envisioned as the core of a home multimedia center. Sony only manufactured about 200 of them before deciding to retool the design.

The new design, known as the PlayStation X, or PSX, dropped the Super Nintendo cartridge port and focused exclusively on CD-ROM-based games. The component hardware inside the console was revamped as well, to ensure an immersing and responsive gaming experience. Launched in Japan in December of 1994, and in the United States and Europe in September of 1995, the PlayStation quickly became the most popular system available.

The CPU in the PSX is a RISC processor. RISC stands for reduced instruction set computer, which means that the instructions and The CPU in the PSX computations performed by processor are simpler and fewer. Also, RISC chips are superscalar -- they can perform multiple instructions at the the same time. This combination of capabilities, performing multiple instructions simultaneously and completing each instruction faster because it is simpler, allows the CPU to perform better than many chips with a much faster clock speed.

To lower production costs, the CPU, graphics and audio processors are combined into a single application specific integrated circuit, or ASIC. Simply put, the ASIC is a customized chip created to manage all of the components that would otherwise be handled by three separate chips.

The games come on proprietary CD-ROM/XA discs that are read by laser, just like CDs. When a game is put in the console, the following happens:

  • You turn the power on.
  • The disc spins up to speed.
  • While the disc is spinning up, the console loads portions of the operating system from ROM into RAM.
  • The game initialization sequence is loaded into RAM.
  • You interact with the game via the controller.
  • As each specific part of the game is requested, the application code and hardware-render geometry are loaded into RAM, while the video and audio portions are usually streamed directly from the CD.
  • The CPU coordinates everything. It receives the input from the controller, pulls the data from RAM and directs the graphics and audio processing. You are finally beaten by the game and turn it off.

Since all information is flushed from RAM when the power is turned off, you will lose any personal game data. But you can save it by using one of the special Flash memory cards. The card is inserted into one of the two slots on the front of the PSX, above the port for the controller.

Controller:

The controller is the primary user interface for the PlayStation. And just as the gamepad that came with the original Nintendo Entertainment System was a radical departure from previous controllers, the PSX controller changed the rules again. With its winged shape and abundance of well-positioned buttons, it is user-friendly and yet powerful.

The standard PSX controller has 14 buttons! They include:

  • four buttons arranged as a directional pad on the top left
  • Start and Select buttons in the top middle
  • four action buttons on the top right
  • two action buttons on the front left
  • two action buttons on the front right

Although each button can be configured to perform a specific and distinctive action, they all work the same way. Each button is a switch that completes a circuit when it is pressed. A small metal disk beneath the button is pushed into contact with two strips of conductive material on the circuit board inside the controller. While the metal disk is in contact, it conducts electricity between the two strips. The controller senses that the circuit is closed and sends that data to the PSX. The CPU compares that data with the instructions in the game software for that button, and triggers the appropriate response. There is also a metal disk under each arm of the directional pad. If you're playing a game in which pushing down on the directional pad causes the character to crouch, a similar string of connections is made from the time you push down on the pad to when the character crouches.

Newer Dual Shock PSX controllers have analog joysticks on them, as well as the standard buttons. These joysticks work in a completely different way from the buttons described above. Two potentiometers (variable resistors) are positioned at right angles to each other below the joystick. Current flows constantly through each one, but the amount of current is determined by the amount of resistance. Resistance is increased or decreased based on the position of the joystick. By monitoring the output of each potentiometer, the PSX can determine the exact angle at which the joystick is being held, and trigger the appropriate response based on that angle. In games that support them, analog features like these allow for amazing control over gameplay.

Another feature of the Dual Shock controller, actually the reason for its name, is force feedback. This feature provides a tactile stimulation to certain actions in a game. For example, in a racing game, you might feel a jarring vibration as your car slams into the wall. Force feedback is actually accomplished through the use of a very common device, a simple electric motor. In the Dual Shock controller, two motors are used, one housed in each handgrip. The shaft of each motor holds an unbalanced weight. When power is supplied to the motor, it spins the weight. Because the weight is unbalanced, the motor tries to wobble. But since the motor is securely mounted inside the controller, the wobble translates into a shuddering vibration of the controller itself. Now let's take a closer look at how the controller “talks” to the PSX.

There are 9 pins on each controller connector. Here's what each pin does:

  1. DATA - This pin carries the signal that the controller sends to the PSX each time a button is pressed. It is an 8-bit serial transmission.
  2. COMMAND - This pin is used by the PSX to send information to the controller. Such information might trigger the motors in a Dual Shock controller at the proper moment. It also uses an 8-bit serial transmission.
  3. Not used
  4. GROUND
  5. POWER - This pin supplies 5 volts to the controller from the PSX.
  6. SELECT - This pin is used by the PSX to notify the controller of incoming data.
  7. CLOCK - This pin carries a synchronizing signal sent from the PSX to the controller.
  8. Not used
  9. ACKNOWLEDGE - This pin sends a signal to the PSX from the controller after each command that is received on Pin 2.