Josh Koffman wrote:
> My read on that was that he's expected to use a consumer USB to 802.11
> adapter, made for use on a home computer or laptop. That might
> preclude the USB to serial chip as I'm not sure there are any that
> act as USB hosts. I could be wrong though. If I'm right, I don't envy
> him at all.

I hadn't even considered that he wanted to drive an 802.11 interface via USB
from his little portable device.  That is **not trivial**, since, among
other things, this requires implementing a USB host controller.

I thought this device was supposed to talk USB and 802.11.  In that case
they would be done separately.  The easiest way to do 802.11 is probably to
interface to a fully canned PC card.  In either case that requires a
protocol stack and a bunch of essentially PCI host logic.  This is not
something that seems a good fit for a PIC.  I'd first look to one of the ARM
varieties that have lots more horsepower and with much of the code available
already.  It will suck a lot more power, both for the 802.11 and the
processor.  Some of the ARM varieties are specifically designed for portable
devices and are reasonably power efficient for the cycles, like the Intel
XScale.  Still, the whole processor part will be a lot more complicated than
a PIC.


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