Geoff Wing <mason@primenet.com.au> typed:
:The NS16450 has a 1 byte memory space.  (The 8250 is similar to this)
:The NS16550 has a 16 byte buffer.
:The NS16650 has a 32 byte buffer.
:The NS16750 has a 64 byte buffer.
:The NS16950 has a 128 byte buffer (and external clocking).

Sorry, I went a bit overboard on the NS prefixes there.  I'm not
sure the NatSemi makes all those, though the numbers are the commonly
used numbers.

Regards,
-- 
Geoff Wing : <gcw@pobox.com>
Rxvt Stuff : <gcw@rxvt.org>
Zsh Stuff  : <gcw@zsh.org>