On Fri, 4 Nov 2016, Eric Smith wrote:
Does anyone have a scan of the MX-80 Dot Matrix Printer Technical Manual?
It may be a long shot, . . . The first printer that IBM sold with the 5150 was a re-badged Epson MX-80.The ROMs are likely to be different, but the rest of its circuitry should be the same.
http://www.minuszerodegrees.net/manuals/IBM_5150_Technical_Reference_6025005_AUG81.pdf ? The original manual had schematics.