The American National Standards Organization, which issues standards for
everything from screw threads to computer languages and character sets. In
1979 ANSI published standard X3.64, Additional Controls for Use with
American National Standard Code for Information Interchange,
which became the
basis for the majority of today's terminal emulations, including
the DEC VT100 terminal and its successors. Prior to X3.64,
terminals were referred to as either full-screen
(such as the IBM 3270 and IBM 5250 series) or
ASCII (such as the Wyse 50/60,
Televideo 9xx, Data General, Hazeltine,
Honeywell, and many others). Terminals based upon the X3.64
standard became known as "ANSI" terminals. Like "ASCII terminals",
they used the ASCII
character-set, but unlike ASCII terminals, they also
used a new well-defined and standard format for escape
sequences which allowed a X3.64-compliant terminal to distinguish between
commands and data unambiguously, even if it did not understand the commands.
This allowed the X3.64
terminals to support a subset of the X3.64 standard and/or add extensions
without breaking other terminals that implemented different subsets or
extensions.
With the introduction of the IBM PC and MS-DOS in 1981 came a
console
device driver, ANSI.SYS, that implemented a very small
portion of the X3.64 standard (11 commands and 3 extensions). This driver
and the IBM PC BIOS and video architecture became the basis for the early
PC Bulletin Board Systems. Users of these
BBSs were told they needed an
"ANSI" terminal, by which was meant
an IBM PC running ANSI.SYS or an emulator for it, characterized by:
- The requirement for a fully transparent 8-bit data path (no parity)
- The use of color combined with IBM PC line- and box-drawing characters (CP437)
- The use of 25 screen lines (instead of the 24 lines on most commercial terminal)
- The use of PC-specific keys
As versions of UNIX and other operating systems were developed for the IBM PC
they inherited similar requirements. Unfortunately, the developers of these
new systems consistently called their terminal drivers "ANSI", even though
each differed from the other, and this has led to a great deal of confusion
for current users of their systems (SCO ANSI is a
case in point).
Here is a list of all Kermit 95's terminal types that are based on
the X3.64 standard. ANSI.SYS identifies a system based on the IBM PC
console driver; VT identifies those terminals derived from the DEC VT
terminals; and X3.64 are those terminals that most closely follow
the original ANSI X3.64-1979 standard:
- AIXTERM
- The native terminal type for IBM AIX (X3.64)
- ANSI-BBS
- For accessing most BBSs (ANSI.SYS)
- AT386
- For accessing Unixware and Interactive UNIX systems (X3.64)
- Avatar0+
- A windowing system built on top of ANSI-BBS (ANSI.SYS)
- BETERM
- For accessing the BeBox (X3.64)
- HFT - IBM High Function Terminal
- Used to access IBM AIX and other systems (X3.64)
- Linux
- Used to access linux systems (VT)
- QANSI
- For accessing QNX systems (X3.64)
- SCOANSI
- For accessing SCO Xenix, SCO UNIX, SCO ODT, and SCO OpenServer. SCO
refers to this terminal type as ANSI (X3.64)
- SNI-97801
- For accessing Siemens-Nixdorf Unix (Sinix) systems (X3.64)
- VT100, VT102, VT220, VT320
- The DEC terminal family. Used to access VMS, Unix, and almost every
other system. The most popular terminal in the world. (VT)
- Wyse 370
- A superset of the DEC VT320 terminal. (VT)
Only ANSI X3.64-1979 terminals are capable of processing
APC command sequences.
ANSI X3.64-1979 was withdrawn and replaced by an international standard,
ISO 6429.
(1) The ANSI American Standard
Code for Information Interchange, identical to the ISO
646 International Reference Version. Since 1967, ASCII has been the
one-and-only universal character set, and will remain so for some time to
come. ASCII has only 95 printable characters, and is therefore not suitable
for representing languages other than English, Latin, Dutch, and a handful of
others. Many schemes -- PC code pages, ISO Latin Alphabets, proprietary
character sets of vendors like Hewlett Packard and Data General, etc -- have
been devised to extend ASCII for other languages, but these are incompatible
with each other, thus ASCII will remain the only universal character set for
years to come, until and unless it replaced by a truly universal character set
such as Unicode or ISO 10646. CLICK HERE for a table
of the ASCII character set.
(2) In classifying computer systems, ASCII-based systems are
those that use character sets based on ASCII for text files, as opposed to
(say) IBM Mainframes, which use a different system called EBCDIC.
(3) In classifying terminal emulations, ASCII terminals are
those, like Wyse 50, Wyse 60, Televideo, HPTERM, Data General, etc, that use
the ASCII character-set but are not based upon the "ANSI"
X3.64-1979 terminal specification.
(4) The "word" ASCII is sometimes used to mean plain text, as distinguished from binary. For example,
"an ASCII file", "transfer in ASCII mode", etc.