VMS Help TCPIP Services, TELNET, TN3270  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    You can run a TELNET session with a host that uses IBM 3270 model
    terminals by using the TN3270 command. The TN3270 command:

    o  Provides IBM 3270 Information Display System (IDS) terminal
       emulation.

    o  Assigns IBM 3270 functions to your DIGITAL keyboard.

    o  Assigns IDS functions to specific keys.

    During a TN3270 session, you can:

    -  Redefine keys interactively (DEF KEY Function).

    -  Redefine keys permanently (Key Definition File).

    -  Record your sessions (Recording Sessions).

    -  Troubleshoot problems (TN3270 Troubleshooting).

                                   NOTE

       When you run TN3270, you can only have one session. You
       cannot have other sessions running simultaneously, as you
       can when running normal TELNET sessions.

    TELNET can emulate the following IBM 3270 model terminals:

    Model                  Screen Size (Rows x Columns)

    IBM 3278 Model 2       24 x 80
    IBM 3278 Model 3       32 x 80
    IBM 3278 Model 4       43 x 80
    IBM 3278 Model 5       27 x 132

1 - Terminal Setup

    When you use TELNET and specify IBM 3270 model terminal emulation
    (TN3270), the image displayed on your screen depends on the type
    of DIGITAL terminal you use (or that your PC is emulating) and
    the features you set on it.

    o  VT200 Series Terminals

       Follow these steps:

       1. At the Set-up Directory menu, select the keyboard type
          that corresponds to the keyboard layout you are using (for
          example, North American).

       2. At the Display Set-up menu, select the following:

          o  Interpret controls

          o  Light text, dark screen

          o  Cursor (visible)

       3. At the General Set-up menu, select the following:

          o  VT200 or VT100 mode (if VT100 mode, set VT100 ID)

          o  7-bit or 8-bit controls

          o  Multinational/national

          o  Normal cursor keys

          o  No new line

       4. At the Communications Set-up menu, select the following:

          o  XOFF at 64 or XOFF at 128

          o  8-bit communication line

          o  8-bit (any) parity

          o  No local echo

       5. At the Keyboard Set-up menu, select warning bell ON.

       At the DCL prompt, issue:

        $ SET TERMINAL /INQUIRE

       The software determines the terminal's characteristics and
       sets the appropriate parameters.

       If you select National Character mode, issue:

        $ SET TERMINAL /NOEIGHTBIT

    o  VT100 Series

       Follow these steps:

       1. Set your terminal to ANSI mode (see the user's guide for
          your terminal).

       2. Enter the following command at the DCL prompt:

          $ SET TERMINAL/INQUIRE

          This command causes the terminal to be questioned about
          its characteristics. The appropriate parameters for the
          terminal are set up according to its response.

       TN3270 requires DIGITAL terminals or DECterm windows that
       support at least 24 lines and 80 columns.

2 - Starting and Exiting

    Start a TN3270 session by using the TN3270 command. You can also
    use the TELNET/TERMINAL_TYPE=IBM-3278-n command. The default
    terminal type is IBM-3278-2.

    You can invoke TN3270 and, without connecting to a remote host
    first, enter certain commands that customize the sessions and
    display parameters or status. You can also use a command file to
    invoke TN3270 and the customization.

    The TN3270 command includes several qualifiers that allow you to
    specify customized or special files for the following:

    o  Character set translation tables file (/CHARACTER_SET=file)
       that translates between EBCDIC and the DIGITAL Multinational
       Character Set. The default file, if set up by your system
       manager, is SYS$LIBRARY:TN3270DEF.TBL. If this file does not
       exist, and you do not specify a file, TN3270 uses its own
       translation table.

    o  Keyboard definition file (/KEY_DEFINITIONS=file) that you
       create as an alternative to the default keyboard layout.

    o  National Replacement Character Set (NRCS) file (/NATIONAL_
       CHARACTERS=n) for which your DIGITAL terminal is configured.
       The default for 8-bit terminals is MULTINATIONAL. The default
       for 7-bit terminals is US_ASCII.

    You can end a TN3270 session (close the connection) in one of the
    following ways:

    o  At the remote host's system prompt, log out.

    o  At the remote host's system prompt, return to the TN3270
       prompt and disconnect the session, as follows:

       1. At the remote host's system prompt, press the TN3270 escape
          character (Ctrl/] is the default).

       2. At the TN3270 prompt, issue either DISCONNECT or close.

    Clearing Error Messages

    TN3270 displays error messages in a bordered display at the
    bottom of your screen. This display overwrites the status display
    and remains visible until you clear it. To clear, invoke one of
    the following functions:

    o  REFR

    o  HELP

    o  SET FIL

    o  DEF KEY

    Recording Sessions

    During a TN3270 session, you can record your screen's contents.
    The PRINT function directs your screen's contents to either a
    file or a spooled printer.

    To record your screen's contents, follow these steps:

    1. Invoke the PRINT keyboard function, as explained in the topic
       Keyboard_Functions.

       The screen display is recorded in a file in a compressed
       state. Null lines (lines with only nulls and attribute
       characters) do not appear.

    2. Invoke the ENTER function or any function that transmits the
       screen contents to the remote host's application, as explained
       in the topic Keyboard_Functions.

    This creates the default output file, TN3270PRINT.LIS. TELNET
    does the following:

    o  Each time you start a TELNET session that runs TN3270, TELNET
       opens a new TN3270PRINT.LIS file.

    o  Each time you use PRINT during a session, TELNET appends new
       output from the screen to the end of TN3270PRINT.LIS.

    o  Each time you use PRINT, if you direct the output to a
       printer, TELNET creates a separate entry in the print queue.

    o  If the printer is spooled, TELNET immediately prints the
       output.

    You can specify a different file name. To change the name, use
    one of the following two methods:

    o  When you start a TN3270 session, use the /PRINTER qualifier.
       Issue:

       $ TN3270 [ host ] /PRINTER=file

    o  During a TN3270 session, follow these steps:

       1. Use the SET FIL keyboard function, as explained in the
          topic Keyboard_Functions.

       2. At the prompt for a new file name, enter a name.

          If you specify the same name that is already in use,
          subsequent PRINT operations direct output to a new version
          of the same file.

       3. Use the NEW LINE keyboard function, as explained in the
          topic Keyboard_Functions.

    Locked Keyboards

    If your keyboard locks, the terminal bell rings, and the status
    line displays:

    Inhib

    To unlock the keyboard, press the following key to invoke the
    RESET function (KP0 refers to the 0 key in the application keypad
    on the right hand side of the keyboard):

 <KP0>

    Do not use the following functions when the cursor is in a
    protected field (a field that does not accept user input):

    o  DELETE

    o  DUP

    o  ER EOF

    o  FM

    o  Any graphic character