Abstract

Operation of a microcomputer-based instrument is controlled by software including a control interface system, a command execution system, and a steady state system. The steady state system includes a group of subsystems operating as concurrent tasks, each carrying out various instrument operations. The control interface system includes a set of subsystems, each responsive to configuration control input signals from a separate control signal source, and each converting configuration control signals into "configuration commands". Each command identifies a particular procedure for configuring the operating state of one or more instrument hardware or software steady state subsystems of the instrument. Each command is stored in memory in one of several queues (one for each control interface subsystem) until the procedure it invokes is carried out. The command execution system includes an arbitrator routine which selects commands stored in the queues according to a predetermined priority scheme and invokes command execution subroutines for carrying out procedures identified by the selected commands. When a command execution subroutine is invoked, it reconfigures one or more instrument hardware or software subsystems according to configuration parameters included in the command.