🚀 go-pugleaf

I am trying to use a terminal emulator called VLT to emulate a vt100
and a Tektronix 4105 to get SAS/Graph output over a 1200 baud modem
from and IBM mainframe running CMS.  Basically, my problem *seems* to
be that VLT doesn't jump into Tek mode when the graphics output starts.

My guess is that I am missing something obvious.  Hope someone can help.
Here's what I am doing...

I run SAS in batch using the CMS command

     R; SAS PLOT

where PLOT SAS contains the following:

Options  Linesize=72;
Goptions device=tek4105 border gwait=5 baud=1200 ;

DATA stuff;
 DO X=0 TO 100 ;
         Y = X + RANNOR(145)*10;
         output;
 END;

proc print data=stuff;

PROC GPLOT  data=stuff;
  PLOT Y*X='+'  ;

run;


SAS prints the usual messages on the terminal, and then spews a bunch
of binary gibberish on the screen, which I suppose are the commands to the
TEKtronix terminal.  This is followed by normal SAS job termination messages.
There are no errors in the log, or anything.

I expected VLT to jump into TEK mode when it received some sort of
TEK initialize message from SAS, but it doesn't.  I've also tried to
manually jump to TEK mode at just the right moment, but so far my timing
hasn't been good.  So, what am I (obviously) missing???

BTW.  According to the VLT docs, it has been extensively tested with SAS
at the labs where it was developed (SLAC, I think, or Livermore).