Re: another question: USB?

[david@uow.edu.au (David Wilson)]

Benjamin O Zotto <zotto@fas.harvard.edu> writes:
>I know that an ethernet card is possible on a IIGS, and a SCSI interface.
>Has anyone considered the possibility of a USB interface?  USB 1.0 has a
>low-speed 1.5Mbit/s transfer mode-- is the IIGS bus capable of handling
>anything like that? (I'm still on the lookout to pickup a Hardware
>Reference). Has anyone looked into the feasibility of this as a hardware
>DIY project?

I think it should be possible - even 12Mbit/sec is only 1.5Mbyte/sec and the
Apple // bus can transfer approx 500kbyte/sec in DMA mode. With sufficient
buffering onboard it could work. The tricky bit would be driver interface
to it (under GS/OS I can imagine a driver, under ProDOS 8 it would seem a
little unlikely).

A quick look seems to indicate that there are plenty of microcontrollers
with USB support for being leaves on a USB tree but none for being the root
(I guess the market isn't there - everyone wants to make devices to plug
into PCs and Macs - much less to make PCs which either have the USB root
in the chipset or get a PCI card to do it).

It would be easier to make the Apple plug into a PC than to make a mouse
plug into the Apple :-(.

What we really need is a PCI bus expansion for the A//. Then you could plug
any PCI card (including 2/4 port USB cards) into it [again software would
be the difficult part]. Might as well hang a PC off the side of the A//
and call it a PCI bus interface :-).
--
David Wilson  School of IT & CS, Uni of Wollongong, Australia