Method and apparatus for minimizing the number of control words in a brom control store of a microprogrammed central processor

摘要

Method and apparatus to reduce the number of control words stored in a read only control store of a microprogrammed unit of the CPU of a large scale computer. A set of control fields are required to control the active elements of the unit to cause the unit to execute a large number of different basic operations. Typically the required set of control fields are included in control words stored in a control store controlling the unit during the execution of a basic operation. Obtaining some of the set of required control fields from other sources available within the unit results in a significant reduction in the number of control words stored in the control store without reducing the functionality of the unit.