System Architecture
Processors and device groups of the PlayStation and how they connect.
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Overview
The PlayStation is made up of processors and device groups centered on a 32-bit RISC CPU. Together they implement all functions such as graphics and sound.1
The PlayStation has the following blocks:
| Block | Description |
|---|---|
| CPU1 | R3000A-based 32-bit RISC CPU with I-cache and scratchpad |
| GTE | Graphics data generating processor |
| GPU | Graphics data drawing processor with its frame buffer |
| SPU | Audio processor with its sound buffer |
| MDEC | Motion decoder |
| CD-ROM decoder | CD-ROM decoder with its CD-ROM buffer |
| PIO | Extended parallel port |
| SIO | Extended serial port |
| OS ROM | OS kernel and boot loader |
CPU and Its Peripherals
Main memory and an interrupt controller surround the 32-bit RISC CPU at the base of the PlayStation.2
The CPU contains an instruction cache and a scratchpad memory.2
Graphics System
The graphics system is made up of the GTE and the GPU.2
The GTE is a coprocessor of the CPU. It performs fixed-point matrix and vector operations for coordinate transformation and light source calculation.2
The GPU draws polygons on instructions from the CPU. The frame buffer is mapped in its own 2-dimensional address space.2
The CPU transfers texture images and color palettes (CLUT) to the frame buffer. The GPU then draws polygons from the coordinates and colors that the GTE computes.2
Sound System
The sound system is made up of the SPU and the CD-ROM decoder.2
The SPU is a 24-voice ADPCM sound source operated by the CPU. It has its own address space with the sound buffer mapped in it.2
The CPU transfers ADPCM data to the sound buffer. Key On, Key Off and modulation information from the CPU make the SPU play it.2
CD-ROM System
The CD-ROM system is made up of the drive, the decoder and the other parts needed to read a CD-ROM.3
Data Expansion Engine
The data expansion engine (MDEC) performs the inverse DCT at high speed. It expands JPEG data and MPEG data compressed within the frame only.3
Controller
The controller passes the player's input to the application. A Multi tap connects more controllers than the two connectors on the main unit.3
Memory Card
The Memory Card stores data that must survive a reset or power off. A Multi tap connects more cards than the two connectors on the main unit.3
Expansion Ports
The PlayStation has two types of expansion port: serial and parallel.3
References
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^ a b Sony Computer Entertainment Inc. PlayStation Hardware. August 1998. Page 1-3, Figure 1-1.
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^ a b c d e f g h i Sony Computer Entertainment Inc. PlayStation Hardware. August 1998. Page 1-4, Figure 1-2.
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^ a b c d e Sony Computer Entertainment Inc. PlayStation Hardware. August 1998. Page 1-5, Figure 1-3.