A method for two-way serial communication with MagStirn 200(2) BiStim units using LabVIEW is described. A suite of LabVIEW virtual instruments' which give simple and reliable control of pulse parameters and delivery is described and made freely available online. The advantages of serial control include the ability to quickly and reliably change pulse parameters during an experiment, to randomly intersperse pulses with different parameters without manually resetting the unit, to deliver pulses with a reliable temporal relationship to other external events, and to control pulse parameters interactively. An application that uses the method for adaptive control of pulse intensity is reported. (c) 2006 Elsevier B.V. All rights reserved.