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DEC-VT330 [16-Jun-87]

 This report is based on a  telephone conversation with Michel Debar  in
 Namur, Belgium who carried out these tests.

 The VT330 monochrome display  is 800H x 480V  (cf. VT240 800H x  240V),
 and uses the  MicroVAX GPX  graphics chip set.   It supports  Tektronix
 401x and Regis graphics.

 PLOT79 DEM01 in Tektronix mode  displays in 45 sec (vs. 131 sec for the
 VT240).  Fill  of a  400  x 400  rectangle in  Regis  mode runs  at  1M
 pixels/sec.  400-pixel vectors  draw at  160K pixels/sec  (horizontal),
 120K pixels/sec (vertical),  and 100K pixels/sec  (diagonal), with  the
 tests performed in  Regis Macrograph to  allow repeated vector  drawing
 without being  limited  by serial  communication  from the  host.   The
 GraphOn terminal, which uses the Texas Instruments graphics chip,  runs
 at about 1 to 2 times this speed.

 In text  mode,  the terminal  barely  keeps  up at  9600  baud  without
 XON/XOFF flow control, and will not run at 19200 baud that way.   There
 is no host control of XON/XOFF (an old problem with DEC terminals),  so
 manual changing in setup is necessary.

 The display is sharper than  the VT240, but some characters  (uppercase
 U,V,W) look odd due to holes in their bitmaps.

 The VT330 has local screen memory which can be configured as 1 page  of
 144 lines, or 6 pages or 24 lines.  However, local control of scrolling
 in this memory is poor---Ctl-Uparrow and Ctl-Downarrow scroll it slowly
 one line at a time.

 Documentation consists of  two 300-page manuals  on text and  graphics,
 plus a third one,  and the manuals  are about as  difficult to read  as
 those of the VT240.