• Registered: 2009-12-09
  • Posts: 21

Topic: max USB speed on a classic?

Anybody any idea what's the maximum bandwidth of the external USB port on a Chumby classic?  I reprogrammed a couple of Classics to run a tiny web browser that shows a page from my home server. However it seems to be very sluggish loading the pages eventough ram and cpu are not maxed out.  I've run a simple throughput test which shows I can get at most 5.6Mbps (using a USB wired 100Mbps adapter). I know the adapter can handle a lot more so I wonder whether the USB interface could be the issue

  • From: Austin, TX
  • Registered: 2009-05-07
  • Posts: 472

Re: max USB speed on a classic?

The i.MX21 processor in the classic supports USB 2.0, but only full speed (12MBs) and low speed (1.5MBs).  That looks about the maximum data rate that you're likely to get to that network adapter.

unwiredben's Website

  • From: Australia
  • Registered: 2008-11-12
  • Posts: 104

Re: max USB speed on a classic?

nicod wrote:

Anybody any idea what's the maximum bandwidth of the external USB port on a Chumby classic?

What size USB sticks are you using? I have a classic & have no hassles with USB sticks under 8G. With 16G+ & podcasts stutter & it takes an age to boot - USB based boot here. Coud you be seeing a similar hassle?

  • Registered: 2012-02-07
  • Posts: 535

Re: max USB speed on a classic?

He's talking about bandwidth of the USB port (how fast data can transfer) as he's using a wired USB ethernet adapter.  You're referring to USB mass storage wink

12Mbps, after you chop off overhead and other inefficiencies, is likely never going to see more than 8-9Mbps peak throughput.  Add in TCP/IP overhead and the like, and you will likely never see more than 6-7Mbps throughput on a good day.

  • Registered: 2009-12-09
  • Posts: 21

Re: max USB speed on a classic?

Yep, I was talking about a USB ethernet adapter indeed. So it seems 5.6Mbps is about the most I can get anyway. Seems I will just need to make my files smaller :-)

Thanks for the quick replies.