Re: Upcoming project: virtual hard drive for //c and IIgs

[Steven Hirsch <snhirsch@gmail.com>]

Peltier Cedric wrote:

> > There are plenty of examples out there showing how such a driver might 
> > be done for Linux.  Poke around for sio2pc (Atari) and Drivewire 
> > (Tandy CoCo).

> Maybe a driver for the smartbus is possible under linux, but I don't 
> know if we could sample reliably a 250KHz serial line through even 
> modern PC I/O under a multitasking environnement (I will give it a try) 
> without a dedicated hardware. From my point of view, using such 
> dedicated hardware on a modern system look pointless for the task, 
> better to do a stand alone system from scratch interfacing the smartbus 
> to IDE or SD. I hope I exposed constraints clearly.

I don't know enough about the smartbus protocol to speak authoritatively, but 
the parallel port hardware on more recent systems should be capable of 1Mhz. 
operation.  How tight are the timing margins?  Where can I find a timing 
diagram for the bus?

If it could be done with a small amount of logic or FPGA, that would still be 
of interest to me.

Steve