Improved Micro-Code Overlay With Latched RAM Outputs
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-01
Latched data outputs from a control storage RAM are utilized to make a control word available for execution when overlaying the control storage of a processor. The processor achieves improvement in overlay throughput by executing the overlay control word as fast as the main storage controller provides overlay data. A microprogrammed computer system, such as the IBM System/38, does not necessarily have all the micro control words residing in th control (Image Omitted) storage at all times. When the portion of the micro control word set that is not in control storage is needed, an overlay is done to write the needed words in the control storage.