I have finally gotten around to scanning pages 79-97 of the HP3421 user's guide. These pages contain the compact programming reference guide. They are not pretty (darn HP (Un)Intelligent scanning software!), but the info should be useful. They can be downloaded at http://nazas.autonoma.edu.co/hp3421/ Regards, carlos. -------------------------------------------------------------- Carlos E. Murillo-Sanchez carlos_murillo(a)nospammers.ieee.org