Documentation is in serio.doc. Will not work under windows 3.x. Will work under windows 95 if you disable the desired serial port in the control pannel. The supplied djgpp.djl is required to link correctly. Read and grok the section on locking code and data in serio.doc. If you have any questions, email me at: Bill Currie or (if the above bounces): djgpp@delorie.com