摘要 |
A modularly-structured integrated services digital network (ISDN) communication system comprises a system processor that should be available for a real-time operating system and for a timesharing operating system. In order to enable continuous transitions of the system processor from one operating system into the other operating system, the task having the lowest priority (idle task) and a program subsystem having comparatively high priority in the real-time operating system (multitasking operating system) are fashioned as branch subsystems in which an assignment change from the addressing tables of the real-time operating system onto that of the timesharing operating system occur. The program subsystem with comparatively high priority which is fashioned as a branch subsystem assures that a certain minimum portion of the calculating capacity of the system processor is assigned to the timesharing operating system independently of the traffic load of the real-time operating system. |