| 摘要 |
A method is described for storing the contents of control registers when it is necessary to interrupt a program being processed in order to process a higher priority program. A usage register is provided for the general purpose registers in a program control unit, each general purpose register being assigned a stage of the usage register. The state of each stage of the usage register indicates whether the corresponding general purpose register is occupied with processing a program. When the latter program is interrupted, the contents of the usage register, the basic registers and the general purpose registers being used for processing the interrupted program are written into storage. Thus, only the contents of the previously employed general purpose registers need be read out of storage after the higher priority program is completed. |
