[nt]roff drivers for EPSON printers

[Chip Rosenthal]

In article <356 at ssp2.idca.tds.philips.nl> mbrands at idca.tds.PHILIPS.nl (Manfred Brands) writes:
>- Nroff uses file from /usr/lib/term.

I post because somebody else might be interested.  There are two parts
to my solution to using SCO's nroff.  I've implemented it for HP LaserJet
and Okitdata 193-type printers.

The first part is the nroff driver tables which include the appropriate
escape codes and special characters.  The second part is a filter called
"colpr", which serves a number of functions.  First, it filters backspaces
into multiple printhead passes.  Second, it performs line folding/truncation.
Third, it performs NL to CR/LF translation.  Finally, it cooperates with
the driver tables to access the full 8-bit character set.

>	I can't get characters in the driver having the eight bit on.

That's correct.  My solution was to use a flag character in the nroff driver
table to set the eight bit.  I arbitrarily chose DEL (octal 177) as the
flag character.  For example, to generate an octal 201, my nroff driver
table emits the two character sequence { DEL, 001 }, and "colpr" restores
it.

However, if you are using this, you can't use the "col" program.  If you
run "col" before "colpr", it strips the DEL characters.  If you run "col"
after "colpr", it strips the MSB.

>- Troff generates files for a C/A/T phototypesetter

There is a filter in the USENET archives called "cat2dit" which translates
C/A/T codes to ditroff output.  I've been told that there are some problems
with this filter, but I believe Mike Slifcak <slif at oliven.atc.olivetti.com>
has hacked on it enough to get output from SCO's troff to work with Rick
Richardson's jetroff.
-- 
Chip Rosenthal / chip at vector.Dallas.TX.US / Dallas Semiconductor / 214-450-5337