Quentin wrote:

> You talking interface like the 232 stuff (MAX232 etc.), which
> condition the signal?  Or is is for encoding, which I suppose the PIC
> can do?

  The latter of course.

  The point I was making with some subtlety(;-) is that the USB is far
*too fast* for a PIC to follow, and the protocol a little complex.  If
either of these things were not the case, and a PIC could do it, then
*why* would they be developing it in the first place praytell?  What
possible use would a *slightly different* version of a slow serial
interface be?

   In combination, there is obviously no way you can possibly do it with
a raw PIC.  Either wait for a PIC with USB hardware inbuilt, or you add
an interface chip.  If you are going to do the latter, you have just
snookered yourself because 1} you *now* have to decide whether to use
asynchronous serial, IÓC or a parallel interface to the PIC and
2} you've jacked up the cost by something like the price of a PIC.

  If your aim was to improve the interface out of the PIC, you've got
absolutely nowhere, and that was I believe, the question as asked.  If
the question was "I have a PIC and I *must* interface it with USB", then
you have no choice anyway.

> OTHA, I am sure USB prices will drop as it gets more popular.

  OTHA?

  Of course they will.  Already are doing; Dave Johnson wrote:

> There are USB controllers available for about a dollar, US.  So not
> bad at all.

  .. and someone mentioned a mouse with a single chip which is either an
ASIC or an embedded processor with USB hardware interface.

Harold M Hallikainen wrote:

> However, Microsoft wants to get rid of all ports but USB, so are we
> gonna be forced to go there?

  Well, yes, and in the same way and to the same extent that 386s and
486s are obsolete and not used anymore.  The fact is, that PCs have an
unworkable interrupt architecture, severely limiting the number of
devices connected.  USB is primarily a way of avoiding this by
effectively sharing one interrupt, supposedly possible with PCI but
historically a deficiency of DOS.

> How about Microchip adding USB to the PIC?

  Of course.  In their own good time.

Steve Lawther wrote:

> As the iMac is USB only, and Intel's latest concept PCs also are, I
> think USB is going to become the interface of choice (but it'll
> probably be a year or two still!).

  It's funny you mention the Mac which was after all, built on the USB,
or at least its slower predecessors (ADB and AppleTalk)!

> However, it is a more difficult port to write drivers for,

  Oh dear, M$ must be involved!
-- 
  Cheers,
        Paul B.