A data acquisition system for the wide angle shower apparatus (WASA)

A new data acquisition system based on concepts such as data switches and multiple-processors is described. The main topic is how data coming from a multicrate front-end in CAMAC, VME and FASTBUS are transported over different links to a buffer-matrix data switch and further into a farm of microprocessors. Modularity, scalability and multilevel data monitoring are important parts of the design goals that are presented. The system is intended for use in an experiment searching for rare events where high interaction rates are necessary and where a fast and selective trigger is difficult to define. Other experimental constraints, the trigger logical structure and the performance of the data acquisition are also described