27 Feb
2013
27 Feb
'13
2:22 p.m.
Back to possible ways of solving the original poster's question- Any
chance you have a terminal server, for example a Digi PortServer? Or
have any hobby budget to pick one up? Mine cost me around $35.
As an experiment I just set up SIMH V3.9-0 on a Windows 8 system
running RT-11 Version 5.3 and connected a real CIT-101 (VT100 clone)
to the SIMH console through a Digi PortServer 16. (Too lazy to dig out
my real VT100 right now).
On SIMH I did this:
sim> set console telnet=1173
Listening on port 1173 (socket 180)
Then on the real CIT-101 at the PortServer prompt I did this:
#> telnet 192.168.1.103 1173
Then back on SIMH I did this:
sim> boot rl0
And then the real CIT-101 terminal was connected to the SIMH console
running RT-11.
On the real CIT-101 terminal in the SET-UP B screen Auto XON-XOFF was
enabled in the Group 2 Position 4 bit, which is the default.
On the Digi PortServer if I disabled its XON/XOFF flow control for
output data and output a large amount of text to the CIT-101 terminal
(for example "TYPE DU.MAC") I would get some of the buffer overflow
error characters displayed on the CIT-101 terminal. If I enabled
XON/XOFF flow control on the PortServer and output the same amount of
text I wouldn't get any of the buffer overflow error characters and
the OFC Output Flow Control LED on the PortServer would blink at times
indicated that the output was being flow controlled.
So with your real VT100 terminal connected to a SIMH console you most
likely need XON/XOFF flow control at the far end serial port where the
terminal is directly connected and not flow control running in the
emulated CPU software. I was able to get the far end serial port
XON/XOFF flow control by connecting the real terminal to a port server
which was doing the flow control. If your real terminal is connected
to a Linux console I don't know enough about that to know whether or
not or how you can enable XON/XOFF flow control there.
-Glen