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Moving An Embedded Project From x86 to PowerPC

An anonymous reader writes "This series on embedded development shows you how to migrate a project prototype from x86 to PowerPC. This initial installment explains the realities and rationale of the project: it introduces the robotic submarines that were the start of the project (and where they came from), and describes the Linux/GCC development environment and the bare-bones Kuro Box PowerPC development board."

4 of 16 comments (clear)

  1. You mean... by 2nd+Post! · · Score: 4, Insightful
    Develop on PowerPC and then migrate to the x86?

    But I quote from the article:
    These processors are large and extremely energy-hungry; active cooling is almost universally required in x86 designs, and mains power is preferable. The dominant design factor steering x86-based designs is the baggage required by backwards compatibility (both in the CPU core and other support circuitry on the motherboard), and many people are doubtless aware of the history behind this. Vast effort has been invested to modernize the CPU and overall system architecture, but even the current 64-bit architectures are constrained to some degree by legacy considerations. There are relatively few true SoC offerings based around an x86-compatible core, and thus significant external circuitry is always required in x86 systems. It should also be noted that, unlike the vast majority of embedded devices, x86 chips lack on-chip JTAG or other hardware debugging interface support.


    The problem is how to hook up mains, active cooling (liquid maybe?) and designing the external support circuitry for x86.

    The PowerPC doesn't have that problem because:
    one tends to find ARM in low-system-cost, high-volume applications, particularly where power consumption is the prime criterion; x86 is typically found in applications where PC-compatibility is the prime selection criterion, and PPC is often found in applications where performance is the prime criterion. The specific advantages I was hoping to realize in moving to PPC were reduced power consumption, elimination of active cooling (required in my Geode design because of the combined power dissipation of the CPU and its mandatory companion IC), and enhanced performance in some digital image processing (machine vision) code.


    So the answer? PPC has lower thermal constraints, higher performance given fixed energy requirements, and lower part count.
  2. Re:Other way around by LWATCDR · · Score: 2, Interesting

    No.
    x86 is not the end all and be all of computers.
    It fails at things like power to mips. Just remember the fastest computer Blue/Gene does not run x86.
    Even Microsoft is dropping the X86 for the new XBox.
    x86 is not dead yet thanks to AMD but it will be interesting to see what the future holds.

    --
    See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
  3. Re:McCraigor wiggler by Amiga+Trombone · · Score: 2, Interesting

    It's a shame he hosted his project on Windows, I would have like to have seen it on OS X or Linux.

    Where do you see that he hosted it on Windows? He hosted it on a Kuro Box, which is a Linux-based PPC device. The only role Windows plays is running the setup program to load the Kuro system image.

    Actually, you can even get around that. Someone on the Kuro forum put together instructions for loading the system image from a Mac.

    The Kuro Box is a pretty neat toy in it's own right. If you want to play around with Linux development on a PPC platform on the cheap, it's certainly the way to go.

  4. Re:insane really use a Mips or ARM SOC by 2nd+Post! · · Score: 2, Insightful

    Sure, but these guys went from x86->PPC successfully, so should and did are two different things.

    I'm sure there are reasons for all these architectures. The PPC has the benefit of being reasonably scalable too: There are PPC cores from 200MHz up to 2.5GHz so you can develop on one and deploy on another.