METHOD OF GENERATING ADDRESSES TO A PAGED MEMORY

摘要

METHOD OF GENERATING ADDRESSES TO A PAGED MEMORY An input-output processing system which performs communication and control functions in a larger data processing system includes a processor for address development to paged memory and program instruction execution for I/O command sequences. In generating memory addresses, instructions are provided an address syllable which references a processor register as an index and a displacement. The contents of the register and the displacement define a memory effective address. A scratchpad memory is provided for storing page table words in levels corresponding to priority levels of processes, and stored page table words are accessed according to the least significant bits of the page number of the effective address. A page base address is taken from an accessed page table word and is concatenated with the effective address to define an absolute memory address.