VT Emulation

For connection to ASCII hosts, Z and I Emulator for Windows provides the VT Emulator for VT340, VT100, and VT52 terminals. ASCII hosts commonly use these terminal control sequences as standards for session presentation, and many ASCII-host application programs assume a VT-compatible terminal. VT emulation allows your personal computer or workstation to operate as if it were a VT terminal. Software that is designed to operate a VT340, VT100, or VT52 terminal should work correctly with the Z and I Emulator for Windows VT emulator.

Although the keyboard layout on VT terminals is similar to that of the personal computer, there are some exceptions. See Default Key Functions for the VT Emulator Layout for the default mapping of keys for VT emulation.

For file transfer to and from ASCII hosts, using the XMODEM and YMODEM protocols, see Using XMODEM and YMODEM.

VT connections to non-ASCII hosts, such as the IBM® zSeries are also possible if you have the appropriate communication devices.

Configuring a VT Session

Use the Customize Communication -> ASCII Host panel to select values for the parameters that define your ASCII host session. There are two types of parameters: Session and Link.

Customizing the VT over Telnet Attachment

  1. Click Communication from the WorkStation-window menu bar.
  2. Click Configure from the Communication menu.

    The Customize Communication window opens.

  3. Select the ASCII host and then select the LAN or COM Port interface.

    The available attachments appear.

  4. Select VT over Telnet attachment.
  5. Click Session Parameters.

    The Session Parameters -- ASCII Host window opens.

  6. Set the Session Parameters (see Session Parameters).
  7. Click Link Parameters.

    The TelnetASCII window opens.

  8. Enter the host name or IP address.
  9. Optionally enter the port number, change the terminal ID, or select the Auto-reconnect check box.
  10. Click OK until the Customize Communication window closes.

    Customization is complete.

Session Parameters

These parameters correspond to setup choices on a VT340 terminal.

In the Online state, the emulator receives data from the host computer, and can send data to it. In the Local state, data you enter on the keyboard appears on the screen, but is not sent to the host; data from the host is held, and not presented on the screen until you change the state to Online.
Operating Mode
Select Char if the host does not echo the characters you type on your keyboard. The VT emulator displays them as it sends them to the host.

Select Echo if the host echos your keyboard characters for display. The VT emulator displays them only as they return from the host.

If you see doubled characters, you should select Echo instead of Char. Echo is the default.

Machine Mode
There are four machine modes. These are:
VT340 mode, with 7-bit controls
This is the default. This mode is recommended for most applications.
VT340 mode, with 8-bit controls
The emulator is set for an 8-bit environment with 8-bit controls.
VT100 mode
This mode is intended for situations requiring strict compatibility with the VT100 terminal. In general, the VT340 7-bit mode is appropriate for applications that expect a VT100.
VT52 mode
This mode is only for applications designed for the VT52 terminal.
Screen Size
You can choose the number of rows and columns that the session screen displays. The choices are The defaults are 24 rows and 80 columns.
Type of Host Code-Page
The choices are for the host code page are National, PC, and Multinational. Multinational which selects the 8-bit DEC Supplemental Graphic Character Set is the default. If you select National, then you must select a country from the Host Code Page pull-down list. The PC option selects the PC Code Page 437.
ISO Latin 9 (ISO 8859-15) character set support for ASCII (VT) sessions
Support of the ISO Latin 9 (ISO 8859-15) character set is available for ASCII (VT) sessions.

Optional Parameters

These parameters correspond to setup choices on a VT340 terminal.

Reverse Screen Image
Check this box to reverse the foreground and background colors.
User Feature Lock
Check this box to lock the following functions so that the host cannot change them.
Auto Wrap
Check this box if you want the VT emulator to start a new line whenever the current row of characters reaches the end of line.
Auto-Answer Back Message
Check this box if you want the VT emulator to send a message automatically to the host, once a connection has been established.
Move Cursor on Mouse Click
Select this option if you want the cursor to move when you click the left mouse button in the session window presentation space.
Answer Back Message
Enter the message, which is a maximum of 31 characters, to send to the host when communication is established.
If you check this box, your answerback message is not displayed in the configuration window. After you conceal your message, the Conceal box has no effect, and the message remains concealed until it is changed.
User Defined Key Lock
Check this box to lock user-defined keys. For example, you can select User Defined Key Lock and define the values of the F6 to F20 keys. These keys are then locked with those values and cannot be redefined by the host.
Transparent Mode
Check this box to cause the VT emulator to display control characters rather than interpreting them.
The attributes of the selected model are sent to the host computer. Choose one of the following: VT100 ID, VT101 ID, VT102 ID, VT220 ID, VT240 ID, VT320 ID, or VT340 ID.
History Logging
When this option is enabled, text is logged into the VT history window as it scrolls off the screen from the top margin row. The top and bottom margins are set when the host application defines the scrolling region.
History Logging Buffer Size
Use this list to select one of the available sizes for the history log buffer. The choices are 16KB, 32KB, 64KB, 128KB, and 512KB. The default is 64KB.
History Logging - Enhanced
Data erased due to the Erase in Display command is scrolled into the history window. See Enhanced History Logging for more information.

Advanced ASCII Host

The Advanced button takes you to the Advanced ASCII Host dialog. The Advanced Options dialog contains all of the configuration options needed for the Local editing feature of VT340 Emulation. The following list defines these configuration options. Default settings are indicated in bold.

Graphics Cursor
Determines whether the graphics input cursor is shown when in graphics mode. Possible values are Enabled or Disabled.
Sixel Scrolling
When this option is selected, a sixel graphics image scrolls to the next row when the last column is reached. Possible values are Enabled or Disabled.
MacroGraph Reports
Controls the ability of the host to retrieve stored macro graph procedures. Possible values are Enabled or Disabled.
Edit Mode
Selects whether local editing is available and the current mode of operation. Possible values are Unavailable, Interactive, or Edit.
Erasure Mode
Determines which characters can be erased in edit mode. Possible values are Unprotected or All.
Edit Key
Determines how the VT340 emulation switches between interactive and edit mode. Possible values are Immediate or Deferred.
Determines how the VT340 emulation sends a block of data to the host system in edit mode. Possible values are Immediate or Deferred.
Application Keys
Determines how the unshifted function keys F6 through F20 work in edit mode. Possible values are Disabled, Immediate, Prefix, or Suffix.
Guarded Area
Determines whether protected characters can be sent to the host system. Possible values are All or Selected.
Selected Area
Determines whether the VT340 emulation can send all characters or only selected characters to the host system. Possible values are All or Selected.
Multiple Area
Determines whether VT340 emulation can send all selected areas on the page, or only the area selected with the cursor. Possible values are Multiple or Single.
VT131 Transfer
When Line Transmit Mode is disabled, this feature selects an ANSI-style or VT131-style data transmission. Possible values are ANSI or VT131. The size of the block depends on the Transfer Termination Mode value.
EOL Characters
Allows you to select characters used to indicate the end of a line (EOL) in a data block. By default the VT340 emulation sends a carriage return (CR). Up to six hexadecimal characters can be specified.
EOB Characters
Allows you to select characters used to indicate the end of a data block (EOB). This feature has no default. Up to six hexadecimal characters can be specified.
Page Coupling
Determines whether to automatically display a new page when the cursor moves to a new page in page memory. Possible values are Enabled or Disabled.
Line Transmit Mode
Allows you to send characters one line at a time to the host system. Possible values are Disabled or Enabled.
Transfer Termination Mode
When Line Transmit Mode is disabled, this feature determines whether the VT340 emulation sends a partial page or the scrolling region. Possible values are Enabled or Disabled.
Space Compression Mode
Determines how the VT340 emulation sends unused character fields and spaces in a data block. Possible values are Disabled or Enabled.

Link Parameters

The Configure Links button take you to a panel for configuring the details of the connection to the ASCII host computer. The panel you see depends upon the attachment type that you chose for your ASCII host. There are two types:

Configuring Links for VT over Telnet

The VT over Telnet attachment is an application that uses TCP/IP (Transmission Control Protocol/Internet Protocol) and that enables remote logon to an ASCII host. TCP/IP provides connectivity functions for both local area networks (LAN) and wide area networks (WAN) and includes the ability to route information between LANs and WANs. The major TCP/IP networks--the Internet--use a standardized addressing procedure to ensure that IP addresses are unique and that communication between enterprises is possible.

The VT over Telnet attachment for Z and I Emulator for Windows requires a TCP/IP stack that supports the Windows Sockets Version 1.1 interface. WSOCK32.DLL must be in the Windows system directory or the current path to provide the interface for the stack program and to support the Windows Sockets V1.1 interface.

For the VT over Telnet attachment, you must define the following attachment parameters.

Host Name or IP Address
Specify either the alphabetic name of the target host or its numeric IP address.
Host Name
The name of the target host is a string
Host IP Address
The IP address of the target host is in dotted-decimal notation--for example:
Port Number
Specify the decimal number of the target host's Telnet port. The default, 23, is the standard Telnet port.
Terminal ID
The VT emulator and the Telnet server use the terminal ID for negotiating an appropriate connection. Ask your Telnet administrator for your host's correct terminal ID. When the default box is selected, the default values are selected from the Machine Mode, as shown in the following table:
Machine Mode Default Terminal ID
VT340 DEC-VT220
VT100 DEC-VT100
ANSI ansi
If the session is disconnected from the host, and if this box is selected, you will be re-connected automatically.

The default is not selected.

Using A VT Session

Your Z and I Emulator for Windows VT session works as if you were using a VT340, VT100, or VT52 terminal. For mainframe VT, iSeries®, eServer™ i5, or System i5® connections, the protocol converters have defined VT keyboard sequences, such as F1 or PA1.

The following tables are provided:

Refer to Administrator's Guide and Reference for default mapping of the VT340 keyboard to the PC keyboard, as used by the Z and I Emulator for Windows VT emulator.

Compose Key

The VT emulator supports the VT340 compose key for generating special characters on the display. Before using the compose key, define a key combination that represents it.

Using the compose key involves three separate actions:

  1. Press and release the compose key.
  2. Press and release the first character (see Table 31).
  3. Press and release the second character.

The first and second characters may be typed in either order, except when the table specifies that they must be entered as shown,

Table 31 shows the appearance and name of each special character, the character pair that generates the character, and an indication whether the order of entering the characters is significant.

Table 31. Character Generation (Special Characters)
Generated Character Compose Key, Plus This Pair
Appearance Description First Second Order
Á A acute A ' either
á a acute a ' either
 A circumflex A ^ either
â a circumflex a ^ either
À A grave A ` either
à a grave a ` either
Å A ring A * either
A ° either
å a ring a * either
a ° either
à A tilde A ~ either
ã a tilde a ~ either
Ä A umlaut A " either
ä a umlaut a " either
Æ AE ligature A E as shown
æ ae ligature a e as shown
´ apostrophe ' space either
@ at sign a a either
A A either
\ backslash / / either
\ backslash / < either
Ç C cedilla C , either
ç c cedilla c , either
¢ cent sign c / either
C / either
c | either
C | either
^ circumflex accent ^ space either
} close brace ) - either
] close bracket ) ) either
» close French quote > > either
@ commercial at a a either
A A either
© copyright mark c o either
C O either
c 0 either
C 0 either
° degree sign 0 ^ either
° space either
# space either
É E acute E ' either
é e acute e ' either
Ê E circumflex E ^ either
ê e circumflex e ^ either
È E grave E ` either
è e grave e ` either
Ë E umlaut E " either
ë e umlaut e " either
a feminine ordinal indicator a _ either
A _ either
½ fraction one-half 1 2 as shown
¼ fraction one-quarter 1 4 as shown
ß German ess-tset s s either
micro or mu
Greek mu / u as shown
/ U as shown
» guillemets, closing > > either
« guillemets, opening < < either
Í I acute I ' either
í i acute i ' either
Î I circumflex I ^ either
î i circumflex i ^ either
Ì I grave I ` either
ì i grave i ` either
Ï I umlaut I " either
ï i umlaut i " either
¡ inverted exclamation ! ! either
inverted question mark
inverted question mark ? ? either
o masculine ordinal indicator o _ either
O _ either
micro or mu
micro sign / u as shown
/ U as shown
middle dot
middle dot . ^ either
Ñ N tilde N ~ either
ñ n tilde n ~ either
# number sign + + either
Ó O acute O ' either
ó o acute o ' either
Ô O circumflex O ^ either
ô o circumflex o ^ either
Ò O grave O ` either
ò o grave o ` either
Ø O slash O / either
ø o slash o / either
Õ O tilde O ~ either
õ o tilde o ~ either
Ö O umlaut O " either
ö o umlaut o " either
capital oe ligature
OE ligature O E as shown
oe ligature
oe ligature o e as shown
{ open brace ( - either
[ open bracket ( ( either
« open French quote < < either
paragraph sign p ! either
± plus-or-minus sign + - either
£ pound sterling sign l - either
L - either
l = either
L = either
" quotation mark " space either
§ section sign s o either
S O either
s ! either
S ! either
s 0 either
S 0 either
' single quote ' space either
ß ss German s s either
1 superscript 1 1 ^ either
2 superscript 2 2 ^ either
3 superscript 3 3 ^ either
~ tilde ~ space either
Ú U acute U ' either
ú u acute u ' either
Û U circumflex U ^ either
û u circumflex u ^ either
Ù U grave U ` either
ù u grave u ` either
Ü U umlaut U " either
ü u umlaut u " either
| vertical line / ^ either
capital y umlaut
Y umlaut Y " either
ÿ y umlaut y " either
¥ yen sign y - either
Y - either
y = either
Y = either

Transparent Mode

Table 32 shows the symbol displayed for each character and control code when the VT emulator is in transparent mode. The characters at AA and BA are the feminine and masculine ordinals, respectively. The characters at 1E, 1F, 80, and 9E are underlined, although they may not appear underlined on the output.

Table 32. Character Generation (Transparent Mode)
0x 1x 2x 3x 4x 5x 6x 7x 8x 9x Ax Bx Cx Dx Ex Fx
x0 @ P 0 @ P p p
capital y umlaut
° À Ð à ð
x1 A Q ! 1 A Q a q a q ¡ ± Á Ñ á ñ
x2 B R " 2 B R b r b r ¢ 2 Â Ò â ò
x3 C S # 3 C S c s c s £ 3 Ã Ó ã ó
x4 D T $ 4 D T d t d t ¤ ´ Ä Ô ä ô
x5 E U % 5 E U e u e u ¥
micro or mu
Å Õ å õ
x6 F V & 6 F V f v f v
split vertical bar
Æ Ö æ ö
x7 G W ' 7 G W g w g w §
middle dot
Ç × ç ÷
x8 H X ( 8 H X h x h x ¨ ¸ È Ø è ø
x9 I Y ) 9 I Y i y i y © 1 É Ù é ù
xA J Z * : J Z j z j z a o Ê Ú ê ú
xB K [ + ; K [ k { k { « » Ë Û ë û
xC L \ , < L \ l | l | ¬ ¼ Ì Ü ì ü
xD M ] - = M ] n } m } - ½ Í Ý í ý
xE N ^ . > N ^ m n ¾ Î Þ î þ
xF O _ / ? O _ n
capital oe ligature
oe ligature
over line
inverted question mark
Ï ß ï ÿ

OIA Line Display Messages

During VT emulation, messages unique to VT can appear in certain columns of the OIA line. These columns display only VT messages, and do not display any of the messages that would appear there in 3270 or 5250 mode. Table 33 shows the meaning of each VT-specific message. Columns that are not mentioned in the table show messages common to all Z and I Emulator for Windows modes.

Table 33. OIA Line Display Messages (VT only)
Columns Message Meaning
1 through 7 VT340 7 Machine mode is VT340, seven-bit control.
VT340 8 Machine mode is VT340, eight-bit control.
VT100 Machine mode is VT100.
VT52 Machine mode is VT52.
VTANSI Machine mode is VTANSI.
9 through 12 LOCK Keyboard is locked.
30 through 39 OVERSTRIKE New characters replace the character at the cursor position in Local Edit mode.
INSERT New characters move characters in page memory to the right in Local Edit mode.
61 through 64 HOLD Screen is in hold mode.
66 through 69 EDIT Local Edit mode is enabled.
71 through 72 Pn (n=1 through 6) Current page number.

History Logging

You can use the Windows scroll bar control to view history data from the current VT session. When configuring the session, select the History Logging option and specify the size of the log (see Configuring a VT Session).

When history logging is enabled, text is logged into the VT history window as it scrolls off the screen from the top margin row. The top and bottom margins are set when the host application defines the scrolling region, using the DECSTBM command sequence ((ESC [ Pn ; Pn r)).

Enhanced History Logging

When the host application sends the Erase in Display (ED) command sequence to erase a portion of the emulator screen, the contents can be logged into the VT history window before being erased. To enable this functionality, select the History Logging - Enhanced option, when configuring the VT session parameters.

The format of the host application ED command is ESC [ Ps J, where Ps is one of the following values:

Erases the screen contents from the cursor position to the end of the screen. This is the default setting.
Erases the screen contents from the beginning of the screen up to and including the cursor position.
Erases the entire screen contents.

When the ED command setting is 0 or 1, and History Logging - Enhanced is enabled, then the portion of the screen that is about to be erased will be logged into the history window before being erased. When the parameter value is 2, the entire screen contents are logged into the history window before being erased, regardless of whether enhanced history logging is enabled.