Fw: ISA to USB adapter

Samuel Thibault samuel.thibault at ens-lyon.org
Fri Nov 10 11:49:22 EST 2006

Gregory Nowak, le Fri 10 Nov 2006 09:32:53 -0700, a écrit :
> On Fri, Nov 10, 2006 at 10:19:54AM +0100, Samuel Thibault wrote:
> > I _STRONGLY_ doubt this... The USB stack has changed a lot between linux
> > 2.4.26 and nowadays 2.6.18...
> That's what I thought, but they did say _any_ kernel,

Never trust a commercial :)

> > > On the bright side, they have their own API used to talk to the
> > > usb-connected isa device, and it looks like it does allow you to talk
> > > fully to any isa card.
> > 
> > Oh! Then a free driver could be written.
> > 
> For what, the isa card?

No, for the USB2ISA adapter.  But actually, when digging in the doc,
their "API" is only for _using_ their proprietary module, not the
documentation of the device itself.

> If so, then I didn't see a problem there in the first place. All that
> would be required as far as I know, would be to modify existing code
> that works with the isa card, to communicate with that card using
> their API, over usb.

A mere #include that re-#defines inb/outb etc would be enough, yes.

> > > So, with a bit of coding in speakup, it should be useable,
> > 
> > That should rather be done in the Linux kernel.  Not only blind people
> > would like to use such card...
> > 
> Let me address that comment literally first, and then I'll clear the
> misconception that seems to have arisen here I think. First, I don't
> know why someone other then a blind person would want to use a
> doubletalk pc,

by "such", I was meaning "an ISA card". And yes, people have good old
ISA cards for acquire data, talk to oldies, tinker, ...

> So, if you mean that a free driver for the usb to isa device should be
> in the linux kernel, since everybody would want to use it, I do agree
> there.

That's it, so we agree, my phrasing was just bogus :)

> In that case, as has been done with other hardware, you'd need to
> spy on how the usb device communicates with the system with the
> proprietary code running, and then try to replicate that in a free
> driver, assuming that their lawyers haven't thought ahead of you,
> and already prohibited you from doing such a thing in their license
> agreement.

In Europe, you can always do this if the company refuses to give
interoperatibility information. Hence whatever the licence agreement.


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