VP(4)							     Kernel Interfaces Manual							     VP(4)

NAME

       vp - Versatec printer-plotter

DESCRIPTION

       Vp0  is	the  interface	to  a Versatec D1200A printer-plotter with a Versatec C-PDP11(DMA) controller.	Ordinarily bytes written on it are
       interpreted as ASCII characters and printed.  As a printer, it writes 64 lines of 132 characters each on 11 by 8.5 inch paper.	Only  some
       of the ASCII control characters are interpreted.

       NL     performs the usual new-line function, i.e.  spaces up the paper and resets to the left margin.  It is ignored however following a CR
	      which ends a non-empty line.

       CR     is ignored if the current line is empty but is otherwise like NL.

       FF     resets to the left margin and then to the top of the next page.

       EOT    resets to the left margin, advances 8 inches, and then performs a FF.

       The ioctl(2) system call may be used to change the mode of the device.  Only the first word of the 3-word argument structure is used.   The
       bits mean:

       0400   Enter simultaneous print/plot mode.
       0200   Enter plot mode.
       0100   Enter print mode (default on open).
       040    Send remote terminate.
       020    Send remote form-feed.
       010    Send remote EOT.
       04     Send remote clear.
       02     Send remote reset.

       On  open a reset, clear, and form-feed are performed automatically.  Notice that the mode bits are not encoded, so that it is required that
       exactly one be set.

       In plot mode each byte is interpreted as 8 bits of which the high-order is plotted to the left; a `1' leaves a visible dot.  A full line of
       dots is produced by 264 bytes; lines are terminated only by count or by a remote terminate function.  There are 200 dots per inch both ver-
       tically and horizontally.

       When simultaneous print-plot mode is entered exactly one line of characters, terminated by NL, CR, or the remote terminate function, should
       be  written.  Then the device enters plot mode and at least 20 lines of plotting bytes should be sent.  As the line of characters (which is
       20 dots high) is printed, the plotting bytes overlay the characters.  Notice that it is impossible to print characters  on  baselines  that
       differ by fewer than 20 dot-lines.

       In print mode lines may be terminated either with an appropriate ASCII character or by using the remote terminate function.

FILES

       /dev/vp0

SEE ALSO

       opr(1)

																	     VP(4)