Keeping up with 19200 baud

[Chris Torek]

In article <568 at panix.UUCP> alexis at panix.UUCP (Alexis Rosen) writes:
>This is not my field of expertise, but I believe that the Mac's built-in
>serial ports can't begin to cope with 19.2kbps because they get an interrupt
>for every byte.

It is possible to keep up with 1920 characters per second even with one
interrupt per character, *provided* that the interrupt handler is carefully
hand-coded, or the CPU is extremely fast.  The average 68010 with the
average sloppy `do a few thousand instructions' style interrupt handler
will not keep up.  A somewhat slow 68020 Unix box (the Sun 3/50) with
a reasonably good interrupt handler (i.e., not SunOS 4.x) will, although
it will use most of the CPU.
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris at cs.umd.edu	Path:	uunet!mimsy!chris