450(C)                                     UNIX System V



     Name
          450 - handle special functions of the DASI 450 terminal


     Syntax
          450


     Description
          The 450 command supports special functions of, and optimizes
          the  use  of, the DASI 450 terminal, or any terminal that is
          functionally identical, such as the  Diablo  1620  or  Xerox
          1700.  It converts half-line forward, half-line reverse, and
          full-line reverse motions to the correct  vertical  motions.
          It  also  attempts  to  draw Greek letters and other special
          symbols in the same manner as 300(C).  It  should  be  noted
          that,  unless your system contains text processing software,
          certain commands (e.g., eqn,  nroff,  tbl,  etc.)  will  not
          work.  Use 450 to print equations neatly, in the sequence:

               neqn file ... | nroff | 450

          WARNING: Make sure that the PLOT switch on your terminal  is
          ON  before 450 is used.  The SPACING switch should be put in
          the desired position (either 10- or  12-pitch).   In  either
          case,  vertical  spacing is 6 lines/inch, unless dynamically
          changed to  8  lines  per  inch  by  an  appropriate  escape
          sequence.

          Use 450 with the nroff -s flag or .rd requests  when  it  is
          necessary  to  insert  paper manually or change fonts in the
          middle of a document.  Instead of hitting the return key  in
          these  cases,  you  must  use  the  line-feed key to get any
          response.

          In many  (but  not  all)  cases,  the  use  of  450  can  be
          eliminated in favor of one of the following:

               nroff -T450 files ...
          or
               nroff -T450-12 files ...

          The use of 450 can thus  often  be  avoided  unless  special
          delays or options are required; in a few cases, however, the
          additional movement optimization of 450 may  produce  better
          aligned output.


     See Also
          300(C), mesg(C), stty(C), tabs(C), graph(ADM), tplot(ADM)


     Notes
          Some special  characters  cannot  be  correctly  printed  in
          column  1 because the print head cannot be moved to the left
          from there.

          If your output contains Greek and/or reverse line-feeds, use
          a  friction-feed platen instead of a forms tractor; although
          good enough for drafts, the latter has a  tendency  to  slip
          when  reversing  direction,  distorting Greek characters and
          misaligning the first line of text after one or more reverse
          line-feeds.


     (printed 8/24/89)                                  450(C)