This port is for a printer filter of Canon BJ F850. The filter is
called Canon Bubble Jet Print Filter for Linux and there exist the
filters for other Canon bubble jet printers. By using this driver you
can print out as high quality as you use the Windows driver. See the
below URLs:

WWW: http://www.canon-sales.co.jp/drv-upd/linux/bjlinux100.html
     file:/usr/local/share/doc/bjfiltercom-1.0/html/README.HTM
     file:/usr/local/share/doc/bjfiltercom-1.0/html/INDEX.HTM
     file:/usr/local/share/doc/bjfiltercom-1.0/html/FAQ.HTM

And then this port has a filter "filter850" which is useful to print
out more than one page. If you use it, you add the next entry into
/etc/printcap.

bjfilter850|Canon BJ F850:\
        :lp=/dev/lpt0:\
        :sh:\
        :if=/usr/local/libexec/bjfilter850/filter850:\
        :sd=/var/spool/lpd/bjfilter850:\
        :mx#0:\
        :lf=/var/log/lpd-errs
