A fastbus trigger module for the SLD Warm Iron Calorimeter

A fastbus module, the Cosmic Logic Unit (CLU), has been designed and built to form a muon trigger using the digital data coming from the limited streamer tubes of the Warm Iron calorimeter (WIC) of the Stanford Large Detector (SLD) at the Standard Linear Accelerator Center (SLAC). The trigger configuration can be changed simply by downloading new trigger tables to two levels of fast-access-time RAMs, without interfering with the SLD data acquisition system. The module can handle two different types of trigger configurations: one for muons produced in the e⁺e^- collisions and one for cosmic muons, with the purpose of monitoring and calibrating the whole apparatus on line