Memory contents management system using EEPROM and RAM - compares new data with memory image stored in EEPROM, stores changed addresses of locations and writes corresp. contents in EEPROM

摘要

The system manages the contents of a permanent memory that can be overwritten and of a fast write/read memory which is structured in sections consisting of a number of addressable memory cells for storing a set of data. A memory image (SAB) of the permanent memory (EEPROM) is made in the fast write/read memory (RAM) and a new set of data to be entered in a certain section of the permanent memory is compared with the old set of data in this section of the memory image. The addresses of those memory places of the section in which the content is being changed is noted in a change memory (AS) and at least the changed data is put in the memory image. Then the contents of the memory places noted in the change memory are entered into the corresponding memory places of the permanent memory. USE/ADVANTAGE - E.g. in telephone terminal for storage of telephone numbers. Short access time to contents of EEPROM; allows greater number of changes to memory contents within lifetime of memory.