18 May
2009
18 May
'09
10:26 a.m.
At 05:17 AM 5/17/2009, Johnny Billquist wrote:
Chris Elmquist <chrise at pobox.com> wrote:
And, of course, there's a pretty good chance that this VT05 is
connected via 20ma, not RS232.
(Assumption based on the fact that there's an easy fix in the KL8-JA;
given that this hasn't been used to fix the problem, it's probably not
an omnibus computer. Pre-8/E serial devices were often current loop.)
-Rick
I may have missed some facts earlier in this
thread-- but does the
system
obey hardware flow control such as CTS? ie, if CTS is low, will it be
blocked from transmitting? If that is obeyed by all of your OS and
software, then it is not hard to build a microcontroller that would sit
between the system and the terminal, adding the delays you need on <cr>
while buffering for and hardware flow controlling back toward the PDP-8.
In general, when talking about DEC equipment, the answer to that
question is *always* no, for the simple fact that DEC didn't do
hardware flow control. Hardware flow control is actually against the
RS-232 spec, and DEC didn't abuse standards (unlike most other companies).