4.3BSD-UWisc/man/cat4/va.4

VA(4)               UNIX Programmer's Manual                VA(4)



NAME
     va - Benson-Varian interface

SYNOPSIS
     controller va0 at uba0 csr 0164000 vector vaintr
     disk vz0 at va0 drive 0

DESCRIPTION
     (NOTE: the configuration description, while counter-
     intuitive, is actually as shown above.)

     The Benson-Varian printer/plotter in normally used with the
     line printer system.  This description is designed for those
     who wish to drive the Benson-Varian directly.

     In print mode, the Benson-Varian uses a modified ASCII char-
     acter set.  Most control characters print various non-ASCII
     graphics such as daggers, sigmas, copyright symbols, etc.
     Only LF and FF are used as format effectors.  LF acts as a
     newline, advancing to the beginning of the next line, and FF
     advances to the top of the next page.

     In plot mode, the Benson-Varian prints one raster line at a
     time.  An entire raster line of bits (2112 bits = 264 bytes)
     is sent, and then the Benson-Varian advances to the next
     raster line.

     Note: The Benson-Varian must be sent an even number of
     bytes.  If an odd number is sent, the last byte will be
     lost.  Nulls can be used in print mode to pad to an even
     number of bytes.

     To use the Benson-Varian yourself, you must realize that you
     cannot open the device, /_d_e_v/_v_a_0 if there is a daemon
     active.  You can see if there is an active daemon by doing a
     _l_p_q(1) and seeing if there are any files being printed.
     Printing should be turned off using _l_p_c(8).

     To set the Benson-Varian into plot mode include the file
     <_s_y_s/_v_c_m_d._h> and use the following _i_o_c_t_l(2) call

          ioctl(fileno(va), VSETSTATE, plotmd);

     where _p_l_o_t_m_d is defined to be

          int plotmd[] = { VPLOT, 0, 0 };

     and _v_a is the result of a call to _f_o_p_e_n on stdio.  When you
     finish using the Benson-Varian in plot mode you should
     advance to a new page by sending it a FF after putting it
     back into print mode, i.e. by




Printed 12/27/86          May 14, 1986                          1






VA(4)               UNIX Programmer's Manual                VA(4)



          int prtmd[] = { VPRINT, 0, 0 };
          ...
          fflush(va);
          ioctl(fileno(va), VSETSTATE, prtmd);
          write(fileno(va), "\f\0", 2);

FILES
     /dev/va0

SEE ALSO
     vfont(5), lpr(1), lpd(8), vp(4)

DIAGNOSTICS
     The following error numbers are significant at the time the
     device is opened.

     [ENXIO]   The device is already in use.

     [EIO]     The device is offline.

     The following message may be printed on the console.

     va%d: npr timeout.  The device was not able to get data from
     the UNIBUS within the timeout period, most likely because
     some other device was hogging the bus.  (But see BUGS
     below).

BUGS
     The 1's (one's) and l's (lower-case el's) in the Benson-
     Varian's standard character set look very similar; caution
     is advised.

     The interface hardware is rumored to have problems which can
     play havoc with the UNIBUS.  We have intermittent minor
     problems on the UNIBUS where our _v_a lives, but haven't ever
     been able to pin them down completely.



















Printed 12/27/86          May 14, 1986                          2