Re: Coop. vs preemptive multitasking (was Re: SwitchItpress release)

[toddpw@cco.caltech.edu (Todd P. Whitesel)]

bazyar@teal.csn.org (Jawaid Bazyar) writes:

>  Try copying files over an AppleTalk connection; try formatting a 
>floppy disk.  Any time a Mac or IIgs does a disk access or otherwise
>takes its attention away from the serial ports, it will lose data
>big-time.

Actually on the Mac this still works because of a lot of low-level hacking
to keep polling the serial ports no matter what. When you have a lot of
built-in hardware, this not such a bad idea because you can make it work.
However, it is virtually impossible when you use a truly modular device
system (like GS/OS does) -- which is vastly superior for everything else.

The real solution is to do what the IIfx did and have real coprocessors
on the I/O so you don't even _have_ these interrupt blackouts, since the
main CPU is not the one working with the floppy or the serial ports.

Todd Whitesel
toddpw @ cco.caltech.edu