Run-time reconfiguration and Ada

The authors examine the support of runtime configuration for systems with the following attributes: applications are coded in Ada; target processors are data processors (specifically, MIL-STD-1750A with the extended memory option); and the target architecture is a loosely coupled, distributed system of data processor modules, whose backplane bus is a PI-Bus (or VHSIC Phase 1 IBus), with backplanes interconnected by either a MIL-STD-1553B or a high-speed data bus. The issues involved in implementing a reconfiguration during runtime once the desired configuration has been determined are addressed. Reconfiguration concepts are defined, and Ada constructs needed to facilitate their implementation as the necessary runtime support are discussed. It has been found that real-time systems that are developed in Ada and require runtime reconfiguration used the support of the Ada compiler/runtime. The network operating system also must be cognizant of a reconfiguration so that communication tables can be updated, and reconfiguration messages are given top priority