Setting up the Terminal Server(s) to Allow Program Access to a Serial Port

By default, terminal server ports are configured for interactive use of the
serial ports by a dumb terminal.  In order to read or write to a port with a 
program or to use a port for a new printer, one must change the configuration.
One must first define an LTA device in Kronen and/or Frankenheim and define a 
new "Service" for the server to provide.  Both the VAX(en) and the terminal
server need to be configured for the new Service.

The examples below all refer to setting up a port to use the AOS chiller.
The process of establishing a new printer can be done by imitating the
commands for the Laserjet printer.

Log in as SMTSYS to Kronen and/or Frankenheim and give yourself all privileges
(ALLPRIV).  Edit the file SYS$MANAGER:LAT$SYSTARTUP.COM.  It defines the LTA
devices on the VAX.  Go to the section with the CREATE PORT commands and add a
line with the new port, e.g. 

     CREATE PORT LTA1012: /NOLOG

Along with that define the characteristics of the new device, e.g.:

     SET PORT LTA1012: /APPLICATION/NODE=EKU/SERVICE=CHILLER

The node referred to in SET PORT is one of the two SMT terminal servers (EKU
is the one in the control room and DUSSEL is the one in the office).  If you
look further down in SYS$MANAGER:LAT$SYSTARTUP.COM you will find some
convenient definitions to identify the ports later in the VMS system, and to
set the protection status, e.g.: 

     $DEFINE/SYSTEM CHILLER LTA1012:
     $SET PROTECTION=(S:RWLP,W:RWLP)/DEVICE CHILLER
     $SET TERM/PERM/NOBROADCAST CHILLER

Insert similar lines for the new device.

SYS$MANAGER:LAT$SYSTARTUP.COM is actually the LATCP startup definition and it
is read and interpreted only at boot time. It would, however, be very
inconvenient to boot the VAX just because of a new LTA device.  Therefore, you
have to run the LAT Control Program by typing RUN SYS$SYSTEM:LATCP and type
in the CREATE and SET PORT commands.  (Type HELP if you need instructions
regarding the other LATCP commands such as those to change a definition.)
Then exit from LATCP and type the VMS commands (DEFINE/SYSTEM ... etc.) at the
prompt. 

Next you have to define the terminal server port characteristics.  Again you
define everything in a startup file but also enter the commands in the server
without rebooting it now.  Edit FDISK:[SMT]SERVER_x.SETUP (where x is either
EKU or DUSSEL) and go to the CHANGE PORT commands.  Select a non-used port and 
insert lines like

     CHANGE PORT 7 ACCESS REMOTE BROADCAST DISABLED USERNAME "Chiller"
     CHANGE PORT 7 AUTOBAUD DISABLED SPEED 4800 CHAR 8 STOP 1 PARITY NONE

Normally one would use the same name (here: Chiller) like in the LTA definition.
but USERNAME is only for documentation.  The second line defines a serial
interface with 8 bits 1 stop bit no parity at 4800 Baud. 

Next define a SERVICE named again like in LATCP.  The SERVICE is linking the
port and the LTA device. It MUST be spelled the same as in the LAT$SYSTARTUP
file.  Go to the CHANGE SERVICE section and add something like: 

     CHANGE SERVICE CHILLER IDENTIFICATION "Chiller" PORT 7 ENABLED

(Here, IDENTIFICATION is only for documentation and can be anything.)  To make
those definitions in the terminal server you have to log into the server you
will use by typing MC NCP at the SMTSYS prompt. In the NCP program type CONNECT
NODE EKU or CONNECT NODE DUSSEL.  Hit <RETURN> and type ACCESS and <RETURN> at
the "# " prompt.  (This will not be echoed.)  Enter anything as the username
and type "SET PRIV" and "SYSTEM" as password. You are now in the server and you
can look at the current port and service settings by typing 

     SHOW PORT 7

or

    SHOW PORT ALL

to see a summary of all the ports and services

or

     SHOW SERVICE CHILLER

Then type in the required CHANGE commands and log out bye typing CTRL/D and
EXIT at the NCP> prompt.  That's it.  Next try your luck connecting to the new
device !  

Note that one cannot simply read an LTA device.  In order to establish the
connection, one must first send something (anything) to the device.  Although
one can use the COPY command to COPY from/to device TT (the keyboard/ screen),
in order to keep the connection established between the COPY TT <lta device>
and COPY <lta device> TT, one must ALLOCATE <lta device>. And anything read
from the port this way will be echoed back to the device connected to the
serial port as if you typed that command.  This might confuse the device. 

A better trick for testing a serial port manually is to use the KERMIT or MIDAS 
emulator programs which are normally used to communicate with the modem.
First, re-direct I/O from the MODEM to the device you want to test by typing,

    DEFINE MODEM <device>

where <device> is the name given to the LTA device with the DEFINE/SYSTEM
command LAT$SYSTARTUP.  Next type MIDAS or DIALOUT (for Kermit).  If the
latter, ignore the instructions and type CONNECT.  Now anything you type
is sent to the serial port and any responses are typed.  To exit the
emulator program, type CTRL-G EXIT for MIDAS or CTRL-\ C then EXIT for KERMIT.

If a new printer port was defined, edit the file, SYS$MANAGER:PRINTERS.COM,
and imitate the commands for the Laserjet.  Type these manually in order for
them to take effect before the next boot.

Although, the SERVER_x.SETUP files are described as startup files, that is
really wishful thinking.  No way has ever been discovered to automatically
load the contents of these files into a terminal server.  (Fortunately, they
need only be done if the server has failed and is being replaced with a new 
one.)  The closest that has been discovered is to type out the contents in one
window, log in to the terminal server with another, and use Cut and Paste to
transfer the lines a few at a time to the server.  (Some of the commands
apparently take a significant amount of time and one must give the server a
chance to finish them before the next are typed.)