SEMICONDUCTOR MEMORY SYSTEM HAVING A SNAPSHOT FUNCTION

摘要

In a semiconductor memory computer equipped with a flash memory, use of backed-up data is enabled. The semiconductor memory computer includes an address conversion table for detecting physical addresses of at least two pages storing data by designating a logical address from one of logical addresses to be designated by a reading request. The semiconductor memory computer includes a page status register for detecting one page status allocated to each page, and page statuses to be detected include the at least following four statuses: (1) a latest data storage status, (2) a not latest data storage status, (3) an invalid data storage status, and (4) an unwritten status. By using the address conversion table and the page status register, at least two data s (latest data and past data) can be read for one designated logical address from a host computer.

主权项

1. A memory system, comprising:
a flash memory comprising a plurality of blocks, each of the plurality of blocks comprising physical pages configured to store data; and a controller configured to:
manage a logical area in relation to a first physical page of the physical pages and a second physical page of the physical pages, where the first physical page is configured to store old data and the second physical page is configured to store new data;manage the old data based on snapshot information indicating whether the old data are to be saved.