Monitoring System Operation

The programming techniques discussed so far describe communication between the analyzer and the computer, where the sequence of all data transfer is controlled by a computer program. This section tells how the analyzer can interrupt computer operation when the analyzer has attained a particular state.

The interrupting process is called a service request. Service requests have many applications. They facilitate economical use of computer processing time when the analyzer is part of a large-scale measurement system. For example, after the computer initiates an analyzer measurement, the computer can make calculations or control other devices via HP-IB while the analyzer is measuring. When the analyzer is through, it signals the computer with a service request. The service-request subprogram then determines what the computer will do next. Service requests can also report analyzer errors while interrupting computer processing.

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