🚀 go-pugleaf

>>Or am I dismally forgetful here?

Yes, in this case you have it backwards, AND you are accidentally
attributing the Mac 128K Mac 512, and Mac+'s problem with only supporting 
very very fast interrupts while floppy was transmitting, with apples 22
other computers.

Only the oldests Macs favoored one serial port over the other. 

All Mac II class devices, and SE etc. can handle 57,600 baud just
fine. And that 57,600 baud rate is using 16 times oversampling
on the serial port. In synchronous blocks, the Mac IIfx for example
can handle about 900,000 baud according to Apple. And of course
EVERY Macintosh EVER made since January 1984 is capable of 230,400
baud, for supporting LocalTalk transmission (normally done of
printer port by convention but can be reprogrammed.)

At 230,400 baud Apple is doing 4 times over sampling with the Zilog chip
for reasonable protection against Clock Drift for a 600 byte packet.

I and a friend rewrote Apples serial port to do DOUBLE the 57,600 baud
rate in order to support our Telebit Worldblazers. In fact using
BOTH ports AT THE SAME TIME was possible at 115,000 baud on a non-cached
non-accellerated IIci at my friends place, using a cable direct from one port
to the other. 

ZMODEM transfers were done at 115,000 baud IN AND OUT on two ports and
no problems were encounterred other than near total deprivation of
CPU time to the Mac. (So severe that VIA was not advancing system clock
time, though I hear that Apple has other goodies that recalibrate the
TickCount to the Real Time Clock in spurts (See Develop issue #10)

Believe me, The Mac handles serial better than the NeXT allows currently.

And the computer I own (A IIfx) has dedicated computer subsystems using 
65C02 processors to handle the serial ports. (This is a feature that was
discontinued by Apple years ago and was only put in the Mac IIfx)

You don't need to respond that the Mac hardware sucks when compared to the
NeXT because I totally agree. But The Mac has always had the greatest
communications capabilities in the world and based on the AMAZING hardware
and software goodies demonstrated at WWDC 1992 It will always have it.

BWilliams