Troff for dot-matrix printers

[Advanced Studies Project]

I have read in the Unix Review that there are drivers that allow
troff to be either previewed or quasi-nicely set on dot-matrix
printers like the Epson MX-80.

Sandy Emerson's article in the October/November Unix review
mentions these without much in the way of references.

Are any such drivers available in the public domain or for
a nominal price?

I'd be grateful for any leads.

				  Robert Chatfield (hao!asp)
				  HAO, (ASP)
				  NCAR
				  Boulder CO 80307 (303)-497-1640