A Microprocessor Based CAMAC Data Acquisition System for Use in High Energy Physics

A high energy physics CAMAC data acquisition system is described which consists of a Motorola 68000 microprocessor monoboard system interfaced to two Digital Equipment Corporation (DEC) UNIBUSes. The system can be replicated any number of times (n) as a peripheral device on a host UNIBUS. This allows for n parallel channels of DMA data acquisition on n auxiliary UNIBUSes each with a CAMAC branch driver and 256 Kbytes of memory. Thus, the system reduces the time required to acquire data by a factor of ~n and simultaneously increases the total memory buffer available to the host UNIBUS by a factor of n. Such a technique is useful at fixed target particle accelerators where data is collected at a high instantaneous rates for a small fraction (10-25%) of the overall cycle time.