SD Memory Card Partitioning for Concurrent Multi-Host Access

Solution Overview

Problem

Conventional SD memory cards with wireless LAN functionality face file management inconsistencies when multiple hosts access the same resource, leading to potential file destruction due to simultaneous access, which limits usability by restricting access to a single host.

Innovation Solution

The SD memory card is configured with multiple partitions, each allocated to a different host, and a file system controller manages address conversions to prevent simultaneous writes to the same address, ensuring each host operates on distinct regions and maintains its file management table integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If exclusive control operation is performed to prevent simultaneous access by multiple hosts, then file destruction is prevented, but usability is extremely degraded

Engineering Contradiction:

Improvefile integrityVSAvoidusability

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The memory unit is divided into multiple partitions, with each partition allocated to a specific host. This segmentation allows multiple hosts to simultaneously access different partitions without interfering with each other, thus maintaining file integrity while improving usability. The file system controller manages this partition allocation and prevents writes to regions allocated to other hosts.

Inventive Principle:

Principle #1Segmentation

2Ease of operation

If multiple hosts simultaneously access the same file region, then usability is improved, but file management table inconsistencies occur and files may be destroyed

Engineering Contradiction:

Improveconcurrent access capabilityVSAvoidfile management table integrity

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

A file system controller is introduced as an intermediary between multiple hosts and the memory unit. This controller manages address conversions and prevents simultaneous writes to the same address by different hosts. It maintains the file management table integrity by coordinating access requests and ensuring that each host operates within its allocated partition boundaries.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If address conversion is performed to prevent simultaneous writes to the same address, then file management table integrity is maintained, but device complexity increases

Engineering Contradiction:

Improvefile management table consistencyVSAvoidaddress conversion mechanism

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The memory unit is divided into multiple partitions, with each partition allocated to a specific host. This segmentation allows multiple hosts to simultaneously access different partitions without interfering with each other, thus maintaining file integrity while improving usability. The file system controller manages this partition allocation and prevents writes to regions allocated to other hosts.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS8688870B2Combined wireless and wired access to memory unit

Publication Date: 2014.04.01 KIOXIA CORP

AI summary

According to one embodiment, a communication device includes a first interface, a wireless communication unit, and a memory unit. The memory unit includes a first region used for first access from the first interface and a second region used for second access from the wireless communication unit. Writing to the second region by the first access and writing to the first region by the second access are inhibited.