18 Oct
2007
18 Oct
'07
12:26 a.m.
On 10/18/07, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
Amd as for a teletype, when I built by tripple serial
port for the CoCo
(what's the point of OS-9 without serial ports ;-)), I specifically
included a 1760Hz clock so I could us an ASR33 with it.
Nice.
And how many PCs have a 'user port'?
That's one thing I would certainly
want to hack in somehow.
That's one of my largest complaints with "modern" laptops - no
traditional ("legacy") parallel port. I have, in the past year,
attached LCD displays, a ladder D-A, MCUs for programming, and a real
Dragon's Lair/Space Ace scoreboard to a PeeCee parallel port. It's
not quite as versatile as the User Port on a PET or a C-64, but I'm
still missing my old (i.e., bought in 2005!) laptop.
I _do_ have some "user port"-ish hardware for ISA, though -
essentially one to three 8255s on either a 2/3-length or full-length
card. A couple of them are just meant to hang external cables out the
back to access the I/O, and another couple are also bread-board cards,
with either grids of 0.1"-spacing holes, or real nylon-block
prototyping strips, with a pre-done circuit area for instruction
decode, latch, off-board DC-37 connector, etc.
I have nothing like it newer than for ISA, unfortunately.
-ethan