The three major components of a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer include the vacuum system (including ion source), the magnet and a data system capable of performing the necessary instrument control for desired experiments. Most previous FTICR systems have used commercial data systems based on custom-built electronics controlled by proprietary mini-computers developed in the early 1980's. Here we present a high-performance data system based on a personal computer running user-friendly Windows software and readily available commercial components contained in a VXI chassis and a minimal complement of simple custom electronics. The system uses a VXI pattern generator to control all aspects of the experiment. The flexibility of the pattern generator allows for performance of all current FTICR experimental sequences.