Memory Card Controller Dynamic Partition Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Memory cards, such as SD and MMC cards, lack the ability to support multiple partitions, requiring users to set the entire storage space to a write protect mode for data security, which is inconvenient and limits access control.
Innovation Solution
A method and system for dynamically switching partitions on a memory card by configuring logical blocks to map to physical blocks, allowing the memory card controller to divide storage into multiple partitions and switch between them based on host system requests, using card-specific data and uninterruptible power supply resets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the entire partition of the memory card is set to write protect mode for data security, then data security is improved, but user convenience deteriorates due to requiring identification authentication for every access
Solution Approach 1:
The memory card storage space is divided into multiple partitions, allowing different security levels for different data. The controller manages multiple partitions independently, so users can access non-sensitive data without authentication while sensitive data remains protected, eliminating the need to protect the entire card with write protect mode.
2Device complexity
If the memory card supports only one partition according to standard specifications, then device simplicity is maintained, but functionality deteriorates by lacking multiple partition support
Solution Approach 1:
The memory card controller dynamically switches between different partitions based on host system requests and card specific data values. The controller can change the active partition during operation without reformatting or physical changes, enabling flexible partition functionality while maintaining a simple single-partition interface from the host perspective.
3Adaptability or versatility
If the memory card dynamically switches between multiple partitions, then partition flexibility is improved, but system complexity increases due to dynamic switching mechanisms
Solution Approach 1:
The controller uses card specific data as an intermediary to manage partition switching. Instead of complex direct partition management, the controller reads and writes card specific data to determine which partition to access, simplifying the switching mechanism while maintaining partition flexibility.
4Adaptability or versatility
If the memory card uses traditional partitioning methods requiring host system reformatting, then partition switching capability is achieved, but productivity deteriorates due to system interruption
Solution Approach 1:
The memory card controller performs partition switching autonomously without requiring host system intervention. The controller independently manages partition transitions by modifying card specific data and internal partition tables, allowing the host system to continue operating without interruption while the card switches partitions in the background.
Data Source
AI summary
A method of dynamically switching partitions for a memory card having a plurality of physical blocks is provided. The method includes configuring logical blocks for mapping to at least a portion of the physical blocks and dividing the logical blocks into first and second partitions; coupling the memory card to a host system and setting CSD corresponding to the memory card as a first default value corresponding to the first partition, wherein the host system requests the CSD to obtain the first default value and accesses the first partition according to the first default value; and setting the CSD corresponding to the memory card as a second default value corresponding to the second partition in response to a switch command from the host system, wherein the host system re-requests the CSD to obtain the second default value and accesses the second partition according to the second default value.