Real-time results without real-time systems

The data acquisition system at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University, East Lansing, is based on commodity PC components running an unmodified Linux kernel. A commercial PCI-VME bus bridge connects the readout processors of this system to digitization hardware. While Linux is not a real-time system, this paper shows how we have structured the readout software to meet the requirements of the NSCL without the use of real-time or embedded components.