14 Dec
2001
14 Dec
'01
3:28 p.m.
From: Richard Erlacher <edick(a)idcomm.com>
The 8250 was a fine chip for the application, though I wonder why they used
the
DIP version. There were better choices available, but
they didn't want to
lose
In 1981 there was only the DIP version as surface mount was not a widespread
technology yet.
the serial port board business by putting two of them
on the same card, and
by
that time serial I/O chips tended to have between 2 and
8 ports on them.
In 1981 they did exist, those with more than two ports didn't have second
source and they werent cheap. The 8274 ( the 8088 bus version of the
Zilog SIO) was about 4 times the cost of the 8250(in the fall of 1981)
though it was a far better part and intel would have loved the business.
What's funny is my Leading Edge Model D PC clone used 8251 and put all
the video, floppy, printer and COM1 on the mother board. In my book the
clones often {but, not always} improved a dumb design.
Allison