USB 2.0 Spec implementation?

Posted by: deswong

USB 2.0 Spec implementation? - 06/05/2002 00:19

Will there ever be USB 2.0 compliancy done to the Empeg so that the few USB 2.0 people can acutally upload the music faster?

The only reason why I ask is that my new motherboard comes with USB 2.0 and it would be cool to have the Empeg as the first usb 2.0 device I play with

I would assume it would be just a firmware upgrade, not a hardware modification, would that be true?

Des.
Posted by: smu

Re: USB 2.0 Spec implementation? - 06/05/2002 01:42

I'm sorry, but USB 2.0 would<ol type="a">
  • be too fast for the empeg's CPU anyway (i.e. you wouldn't win much over USB1.1 or 10MBit Ethernet)
  • it would require serious hardware modification. AFAIK, the USB 1.1 controller is built into the ARM 1100 CPU of the empeg, and thus would need to be replaced by a different CPU plus an external USB 2.0 controller etc.
    </ol>Like upgrading from UDMA33 to UDMA66 (or from UltraSCSI to UltraWideSCSI), you need a new controller that supports the speed on a hardware level.

    cu,
    sven

    Edit: Hey Tony, I think this one qualifies for an FAQ entry by now.
    • Posted by: altman

    Re: USB 2.0 Spec implementation? - 06/05/2002 02:37

    USB2.0 wouldn't be too fast for the empeg's CPU; Yes, we wouldn't be able to saturate the bus (by any means) but we would be able to go faster than 10mbit ethernet without a doubt.

    We don't use the SA1100's USB controller, we use an external one. Why? Because the SA1100's USB slave has been severely bugged for a LONG time, and most/all of the SA1100 silicon we had in stock featured the bug. The Mk1 used the Natsemi USBN9602 (arrrrgh, never again, big EMI issues + hardware bugs) - the mk2 used the Philips PDIUSBD12 (bugs & very twitchy about timing). On the mk2 you can remove/fit some 0-ohm resistors and switch the USB to the internal SA1100 if you fancied it, but if your CPU isn't one of the Intel branded ones, it won't work at all. If it is an intel branded one, it won't work if you have more than one USB device on your entire USB subsystem (or so the errata says).

    Basically, no, it won't be "reworked". USB 2.0 is a different kettle of fish to USB 1.1, you can't just twiddle something and have it work - you need new silicon and a new PCB layout.

    Hugo