Mechanical Make Up

Sony Play Station

The CPU in the PSX 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 at 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 regular CDs . When a game is put in the console, the following happens:

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.

The standard PSX controller has 14 buttons! They include:

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 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.

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.

Games
The games on the PSX are CD-ROM-based, so they are limited to a maximum size of 650 Mb. But this is a lot of space. In fact, most games do not use more than a fraction of it for the actual game. What can eat up the space are the incredible full motion video intros and intermissions that PlayStation games are known for.

There is a noticeable delay while the game is loaded from the CD, which you do not get in cartridge-based games. Of course, the trade-off for faster loading is a significantly smaller amount of storage on the cartridge.

Because they are black instead of the traditional silver, PSX CDs are very distinctive. But don't let that fool you. The CDs are just as susceptible to scratches and intense heat as normal audio CDs -- even more so in fact, since a scratch on a game CD can make it totally unusable.