In article <199701192109.QAA13639@amaterasu.sandelman.ottawa.on.ca> you write:
>   The 16550 requires software to toggle the RTS/CTS when the FIFO is
> full. The Zilog does this itself in hardware. (If I'm mistaken, then
> please let me know. This is based on reading of source code and a dim
> memory off hardware specs read years ago)

I don't think that's correct.  The only thing I see about automatic
changing of RTS in the databook is for SDLC mode, where it's used to set
line driver direction or somesuch.  The z8530tty.c seems to handle
RTS/CTS itself. 

I think one of the enhanced 16550 clones (Maybe the Startech 16650, the
one with the 32 byte FIFO?) CAN handle RTS/CTS automatically though. I
wonder how hard it'd be for com.c to learn to suport those?

Another question I've long had, is since the 3/60 doesn't have much in
the way of hardware expandability, how hard would it be to add stuff via
either the socket for the DES chip (probably hard) or the extra P4
connector (the one near the front)? There might be enough people
interested to make a project like that economically viable.  One or two
16654s (4x a 16650 on one chip) on a P4 plus the right software could
turn a 3/60 into a nice terminal server/PPP router.  The ports could be
brought out to a SCSI-II styler connector thrhough that "OPTION" DB25
knockout on the back panel, and then an octopus cable from that to
DB25s. A 3/60 should be able to keep up with 4 or 8 ports of 16650
without too much trouble, I'd think.