Electronics Manufacturing – M528



       The latest ‘play toy’ from Sony is the new Playstation 3 (aka PS3). It is not enough to just call it a game console, a lot of reviews about it has considered it as a ‘multi-function’ entertainment system (Microsoft MSN), some has even gone to the extent of describing it as a form of super computer (The EE Times UK, talking about a statement made by Andrew Rassweiler) .
One can easily hear every kid (both the actual kid, and the ‘big kid’), saying “Have you heard about the new Sony Playstation 3?” but this is an easy misjudgment; I hear you ask me why.
            Well let me start by saying that arguably, the name ‘Playstation 3’ is ‘almost’ about the only thing that Sony owns on this game console. What makes up the console itself is actually designed by a series of manufacturers.
            The Playstation 3 comprises of a series of components to back-up its multiple features. From the new blu-ray technology (which is a slot-loader) to its cell broadband processor engine, it even has touch-sensitive eject and power buttons (which I think adds a bit of style to it). I shall be talking about the vast variety of components present in the Playstation 3, but should be focusing more on the cell broadband processor.
            Personally, I believe the PS3 is a bunch of puzzle pieces put together to make a ‘complete’ and ‘meaningful’ picture. The manufacturers involved in the production of the PS3 provided the puzzle pieces, while Sony put the pieces together. Therefore, I don’t exactly see it as new invention, I believe it’s more of working with what you have, and how it has been put (designed) together.
            What I shall be doing in this article, is introducing you to some of the components that make up the PS3; however, I will be paying particular attention to the processor (Cell broadband engine), and how some of the components work around it.

The main processing unit and perhaps the most complicated part of the PS3 is its main processing unit. It is known as the Cell broadband engine, designed jointly by Sony (yes, you read it right), Toshiba and IBM (the alliance was called ‘STI’, formed in 2000).

The Cell processor has over 234 million transistors onto a single die manufactured on a 90nm silicon-on-insulator process. The cell has nine processing cores. So imagine nine processors working together on one chip, this is extending the current trend of multi-core processing.
In an individual cell, there is:

  • One main processing element (Power Processing Element, ’PPE’)
  • Eight Synergistic Processing elements (SPE)
  • Element Interconnect Bus (EIB)
  • Direct memory access controller (DMAC)
  • 2 Rambus XDR memory controllers
  • Rambus Flex IO interface.

The picture above is taken from the IBM site (Cell Broadband Architecture). It shows a brief overview of all the processors working together on one chip. Its shows the SPEs interconnected by the Element interconnect Bus (EIB).  One can also notice that they all operate on a common memory space even though the both the PPE and the SPEs have different functions.

The PowerPC PPE (64-bit power architecture) is a very powerful processor. Although it is powerful enough to run on its own, or even run a computer (How stuff works: “Playstation 3 cell processor”) it acts as a controller/manager to the SPEs, thereby making the Cell flexible enough to support various operating systems. The PPE consists of a processing unit connected to a 512KiB level 2 cache. Every task that needs to be done goes through the core, which in turn assigns the different tasks to each of the SPEs, taking into consideration the need to achieve the maximum level of performance from the processor.

            There are eight SPEs (running at 3.2GHz) in the cell, each of them a 128 x 128-bit vector processor. However, only seven of them are used, the other one is used as a spare, and its disabled to improve production yields. It only comes into use if one of the other SPEs stops working or in the case of wear and tear. However, only 6 from the remaining seven are used for intense tasks, the seventh one is to deal with aspects of the operating system and security. From the diagram above, it is easy to see that each of the SPEs are capable of working independent of each other, or they can work in collaboration as well, if need be; this gives the cell the advantage of being able to multitask as well. The SPE contains 256KB of non cached memory for local storage (LS in the diagram above), which means that for every instruction the SPE executes, it is directly placed there by the programmer, which might however mean that rather than the whole complexity of the system being placed on the processor, it is entirely up to the programmer; thereby there really can’t be any room for mistakes from the programmer whatsoever, although this process seems to be faster than having a general cache (Dailytech: The Playstation 3 dissected). However, I am a little surprised as to why the SPE needs to be non-cached in the first place, there is always bound to be human errors, so I personally think leaving the processor to handle the complexity of the system would have been a better idea, since the cell itself was built for complex processing (I guess it leaves room for future developments??)

            The Element Interconnect Bus (EIB) connects all the other elements together in a ring-style bus. Although the EIB does not actually deal with any sort of processing itself, but since it connects the different elements in the cell together, it has to deal with the constant data flow going through it to different destinations in the system.

Brief overview of the Graphics

         The GPU (Graphics processing unit) that was created for the PS3 is the RSX (Reality Synthesizer). Personally, I can say this happens to be one of the most interesting parts of the PS3, as it is what you see on the screen, and probably what most gamers would enjoy more. This is the part of the system that makes you feel like you are actually present ‘live’ in a game whilst playing a particular a game. The RSX was manufactured by Nvidia.

The RSX is a 550MHz graphics chip, with over 300 million transistors in total (that is more than there is on the main processing unit of the PS3). It has independent pixel/vertex shader architecture, making it a very high level of graphics.

The PS3 has finally been launched here in the UK (almost 4 months after the rest of the world got the unit). However, only the 60GB one has been released here in the UK so far, which obviously means we only have the expensive one available to us, and from price comparisons, it seems Europe is paying the most money for the PS3 ( a reason I am still trying to understand).
            Also, in terms of compatibility with previous Playstation games, regular downloads and upgrades will have to be made to ensure compatibility. “Rather than concentrate on PS2 backwards compatibility, company resources will be increasingly focused on developing new game and entertainment features exclusively for PS3.” (David Rees; President of SCEE). So does this mean that consumers are being ‘bullied’ into purchasing the PS3, or does this aid the development of new technology in the economy?  There are a few more arguable topics concerning the PS3, and more are arising each day as we all get used to this ‘amazing’ new system (as I think it is not enough to call it a game console anymore).
All I can say is that, until the next latest ‘toy’ is released, we just have to ‘swing on this ride’ for a little while longer.