Group Build at the Mason Dixon Hamfest
wb4jfi at knology.net
Tue Oct 26 14:42:18 CDT 2010
Controlling an embroidering machine is a little different than receiving
I/Q data at 192ks/s (each sample=32bits), or 6Mb/s, over a high-speed
USB2 connection. 480k samples is even worse, with a data rate of over
I'm not saying it won't work, just look out. I have heard of other hams
trying to run PowerSDR, a Windoze program, in a Windows VM under Linux,
and it failed, due to USB compatibility problems.
USB!=USB between different OS's. There can be a high amount of latency
which on lower-speed (HID, CDC, even full-speed) USB devices does not
cause problems. But, given data rates of over 15Mb/s or more, the
inefficiencies in all that API cross-talk/faking-it starts piling up.
And, I think that there is a dramatic difference between usblib
implementations between Linux and Windows. What works fast in Linux,
not so much in Windows. It needs its own tweaking, at least that's what
No first-hand knowledge on the above, as I've seen failures from people
a lot smarter than myself. Maybe just "there be dragons", but it's
enough to keep me from the edge so far. I have other things to waste my
time on right now.
Anyone have any actual, real-world experience running a fast-data
hardware device and software program for Linux on Windows, or vice
versa? A USB scope might be a good example, as the samples are coming
in pretty fast...
Macs are a different issue., I think their implementations are
On 10/26/2010 11:05 AM, Mike O'Dell wrote:
> Parallels on MacOS X also does a great job of forwarding USB devices
> to VMs. My sister-in-law runs her computer-controlled embroidery machine
> from inside Windoze-in-a-VM-baggie just fine.
> USB these days is pretty-much completely encapsulated by software APIs.
> even USB Class Drivers don't really see hardware except
> what's at the end of the "pipes" (a real USB construct).
> and since the USB transfers are highly-structured, only
> the payload, either async or isochronous, is what matters.
> yes, there are commands and responses, but the nature of
> USB constrains real-time events to isochronous transfers.
> from the standpoint of virtualizability, this is a huge
> improvement over the days when pins on a parallel port
> were used as GPIOs stroked in real-time by spin-loops
> in x86 ASM code. (see "bit-banging serial port")
> On 10/25/10 7:44 PM, Louis Mamakos wrote:
>> On Oct 25, 2010, at 6:23 PM, wb4jfi wrote:
>>> On 10/25/2010 5:44 PM, Louis Mamakos wrote:
>>>> On Oct 25, 2010, at 3:23 PM, Frank Gentges wrote:
>>>>> In addition to assembling the boards, we had the Quisk HF radio
>>>>> software up and running as a demonstration that also caught
>>>>> peoples attention. We are now getting a version of Ubuntu that
>>>>> can be run that includes the files for Quisk and the Charleston
>>>>> receiver. We should be able to distribute DVD disks that will
>>>>> bring up Charleston/Quisk/Ubuntu on a computer either as a live
>>>>> load or as a hard drive install. AMRAD member Rob Bowers has been
>>>>> working on this and a big tip of the AMRAD hat to Rob. Stay tuned.
>>>> What would be slick is if this could be also available as a VMware
>>>> virtual machine image of an installation of Quisk on an Ubuntu
>>>> operating system. For those that don't run Linux on their desktop,
>>>> it would be an easy way to use the software. There's a free VMware
>>>> Player<http://www.vmware.com/products/player/> that could be used
>>>> on Linux and Windows to run VMware appliance images.
>>>> Tacos mailing list
>>>> Tacos at amrad.org
>>> I'm not sure that this would work, since the Charleston board uses a
>>> high-speed USB connection to Quisk. The software will probably
>>> function, but the USB drivers may not play right. I've heard of
>>> other USB-based devices having trouble in virtual machines. But, I
>>> do not have any first-hand knowledge.
>> Good point, I don't know if the VMware Player exposes the USB
>> peripherals. I do know that VMware Fusion on the Mac does a great
>> job of exposing USB peripherals. I routinely run Windows XP inside a
>> VM, and use USB serial devices as well as specialized CCD cameras for
>> astrophotography, also connected via USB to the host (and into the
>> VM). At least in the environment, I'd expect it ought to work..
>> Tacos mailing list
>> Tacos at amrad.org
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