This wiki is not longer actively used and, due to years of spam, has unfortunately been locked from further editing by anonymous users. Only approved users can edit the wiki or add content. If you would like to contribute to this wiki, please contact the administrator Benjamin Mako Hill.

Hardware specification

From Pedia
Jump to navigation Jump to search

Hardware details for OLPC, 24 Dec. 2005

V. Michael Bove, Jr., updated by Jim Gettys.

Hardware Design Process

Designing hardware is much more constrained than software; while you may sometimes have great influence on the design of a part many months or years in advance of it becoming available, you can only actually use parts which you can actually get in the volumes required at prices you can afford. This is foreign to many in the free and open source software community who are used to more fluid ability to modify design and produce in unlimited copies. Designing hardware is similar to making sausage: you may grow the ingredients starting long in advance, but you can only make sausage with the ingredients that you can actually get in the amounts you need for the sausage you want to produce.

High Volume Design and Manufacturing

Furthermore, production of high volume hardware is now a very specialized business, and design is now often joint between the organization/company that specifies what the hardware should do, (often to the point of selection of major and minor components), and an "ODM", or original device manufacturer, which generally does the detailed design for production: e.g. exact part selection, schematics, layout, mechanical design, testing, debugging for production, logistics, and production of the finished goods.

In OLPC's case, the ODM is Quanta, selected in mid December. There is a good chance that your laptop was manufactured by Quanta, possibly the largest company few people have heard of, headed by Barry Lam, which manufactures more laptops than any other company in the world, whether branded HP or Apple or others. Detailed design of the first production design is just starting, though OLPC has investigated (and continues to investigate) the possible design tradeoffs.

Note that CPU chip manufacturers generally provide sample designs, development boards, and application notes to explain how their products might be "designed in" to actual products. Our prototype machine seen at Tunis was using one of the AMD "Rumba" boards. It approximated much of the first OLPC hardware, though used a conventional disk rather than NAND flash, and lacked the much cheaper flat panel that is under development. Detailed schematics and layouts of such sample AMD designs are generally available in the chip manufacturer's developer programs. If you are interested in exact design details of hardware could you get for immediate experimentation, we direct your attention to these programs. Most of the information required to program devices, however, is completely freely available at the manufacturer's web sites in fully public specifications.

In concert with ODM's, such sample designs are generally customized to fit the exact product needs; that is the phase of the project we have just entered.

Forseeable Designs

Currently we can forsee three generations of machines: a first one to ship in late 2006, a second production run sometime in 2007 that will incorporate a newer AMD chip and possibly a newer wireless chip, and an E-Ink (or other low-power, bistable display technology) based machine to ship when this new display technology is available at an appropriate price point. The further out, the fuzzier the crystal ball.

We will try to keep this specification up to date as we can as more and more details of the first design (and subsequent designs) are nailed down, and provide links to specifications for the chosen components, and information required to program them.

First Generation System

Details of the first generation are firming up as of the date of this document, and are closely related to the CPU and CPU support chip chosen:

  • Processor: AMD Geode GX500@1.0W with AMD CS5536 companion chip (note that the "500" chip really operates at a 366MHz clock).
  • Memory: 128MB DRAM, possibly DDR Mobile
  • Nonvolatile storage: 512MB (possibly 1GB) NAND flash memory
  • BIOS/loader: hardware details TBD; either conventional, or maybe LinuxBIOS, if available in time.
  • Audio: AC97 codec (chip TBD; we are down to probably two or three alternatives), built-in stereo speakers and mono microphone, jacks for external stereo speakers and microphones
  • External ports: four USB2.0, one supporting On-The-Go functionality
  • Display: dual-mode, based on a 7.2" diagonal 800x600 monochrome TFT panel
    • Monochrome (high-res, low-power "E-Book") mode: 800x600, reflective (ambient light)
    • Color mode: 462x346, quincunx-sampled, LED-backlit
  • Input devices: keyboard, trackpad (supporting pointing, scrolling, and possibly graphical input), additional buttons adjacent to screen for use in E-Book/tablet mode
  • Wireless: Atheros AR5004G or AR5004GS chip, 802.11b/g. The requirements of mesh networking in combination with the abilities of the madwifi device driver have driven this selection; it is the best and most flexible wireless device driver today. There are not other viable alternatives at this time.
  • Power: 100-240VAC, 12VDC, also integrated crank charger based on a permanent-magnet generator and 100:1 gear train. Battery details TBD.

Many of the TBD's should be set by late January, 2006, and we'll try to keep this page up to date.

The display is the only part of this design which is actually new. At this moment, we are pursuing two possible designs in parallel to reduce risk. We will probably not have final details on its details until after first samples can be evaluated in several months.


Second Generation Design

Second-generation unit will use a more power-efficient integrated Geode-based AMD chip (instead of the GX500/5536 set) and probably the Atheros AR6001G or similar wireless chip. Feedback window on design of the next AMD chip will close in March 2006, so it's important to maintain dialogue with AMD regarding Gen 2.

Retrieved from "https://pedia.media.mit.edu/index.php?title=Hardware_specification&oldid=4189"