Method for utilizing a memory interface to control partitioning of a memory module

Abstract

Apparatuses and methods for implementing partitioning in memory cards and modules where conventional memory cards or modules have only a single partition. A representative memory card / module in accordance with the invention includes a memory device(s), and a memory interface which includes a data bus, a command line and a clock line. The memory card / module further includes a memory controller coupled to the memory device(s) and to the memory interface. The memory card / module includes means for controlling the partitioning of the memory device(s), and the memory controller is configured to operate the memory device(s) in accordance with the partition information.

Description

FIELD OF THE INVENTION [0001] The present invention relates to the technical field of memory cards or modules. It also relates to memory cards or modules using flash and / or ROM technology. More specifically the invention relates to a simple way to implement partitioning in memory cards and modules such as e.g. MultiMediaCard (MMC) cards, SD memory cards or Memory Sticks where a conventional memory cards or modules having only single partition. [0002] The present invention relates to memory cards or modules known for example as MMC cards or e.g. SD cards or Memory Sticks. The MMC and SD specification describes a memory card functionality in a certain card form factor and with a certain electric interface and a data exchange protocol for the exchange of data. This invention describes some additional functionality needed to make system more usable and reliable as embedded mass memory. BACKGROUND OF THE INVENTION [0003] The properties of MMC cards are disclosed e.g. in the MMC specifica...

AI Technical Summary

Benefits of technology

[0015] It is also contemplated to define wear-leveling information separately for each partition. Wear leveling information may for example comprise if the wear leveling is activated or deactivated for each partition, and may be also comprise information about which memory (cells or) blocks are actually worn off and which memory (cells or) blocks are used to replace them. It is contemplated to allow only blocks inside the particular partition to be used for the wear leveling of that partition. This kind of “partition internal” wear leveling could minimize data interference between different partitions and simplify recovering after sudden power off.

[0018] It is also envisaged to create the read-only partitions first as continuous space (area of the memory device) and to create read-write partitions after that. This approach simplifies the access to additional spare blocks in case that wear leveling capacities of a partition are not sufficient and need to be extended (partition shifting).

[0021] In still another example embodiment of the present invention a said memory controller is configured to check the correctness of said partition information. It may be checked if the selected partition fits to memory module geometry. It may also be checked if partitions are overlapping. It may also be determined if a minimal amount of spare blocks may be provided for a memory partition to allow wear leveling. It is also contemplated to monitor the partition information and additionally evaluate and reallocate the partitions (e.g. for expanding spare blocks, moving partitions and the like). With these abilities, the memory module is able to accommodate even larger “blackouts” of memory cells / sections / areas. Subsequently to a respective check, a negative result of said checking operation may be output (a positive result of the check may also be provided to a user but will not be considered as providing any useful information). Thereby, a user may be informed that a repartitioning operation is considered necessary.

Problems solved by technology

Therefore, the functionality of internal firmware in case of wear leveling, garbage collection, data compaction, bad block management and other memory technology related issues, which are required for proper card functionality, are card specific and cannot be controlled by host.

This means higher risk of data corruption for example during sudden power-cut-off (power supply interruption) situations (if at the same time erase or write operation internally in card going on) and results in lower data security.

Images