Address mode facility for microprocessor - holds address mode information in memory for call up by microprocessor

摘要

A facility enables the address mode of microprocessor systems to be selected to accommodate a range of applications. The addressing mode capability depends upon the number of working registers used multiplied by the number of base 2 stages used. The system uses an address mode store (10) consisting of eight lines and three rows. The memory is loaded at the start of the programme by a write control stage (11) coupled to a decoder (12). The content of the memory is read during the processor operations and the address mode decodes (14) for input to the microprocessor.