A Microprocessor-Based Controller for Nuclear Instruments

A microprocessor-based digital controller was developed to control the operational modes and the data output of a nuclear PHA (pulse height analyzer). The controller communicates with the PHA via a full duplex serial communications line. Only four wires are required between the devices; therefore, this method is very desirable for remote applications when the nuclear detector and PHA may be distantly located from the controller. The I/O (input/output) device for the controller is a standard 110-baud keyboard terminal or a 2400-baud interface. A SC/MP-II (Simple Cost-effective MicroProcessor) with firmware (permanent software) provides the control functions and output data formatting. The firmware may be easily changed to control other instruments.