Memory Module Register Access via Device ID Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing memory modules lack independent access to internal registers and devices via side-channel buses, hindering system debugging and failure analysis due to shared bus connections.
Innovation Solution
Implementing a registering clock driver (RCD) with a side-channel interface to configure device identification numbers, enabling selective access to individual memory and buffer devices through in-system access modes, using a shared error signal to read/write registers without interfering with normal system operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a shared bus connection is used to connect memory devices and buffers, then device complexity is reduced, but independent access to internal registers becomes impossible
Solution Approach 1:
The patent segments the bus connection structure by introducing individual side-channel bus connections for each memory device and buffer, separate from the shared command bus. This segmentation enables independent access to each device's internal registers through dedicated side-channel interfaces, resolving the contradiction between ease of operation and device complexity.
Solution Approach 2:
The patent introduces side-channel bus interfaces as intermediary connections between the RCD and each memory device/buffer. These intermediaries provide independent register access paths without disrupting the main command bus architecture, allowing simultaneous operation of multiple devices while maintaining structural organization.
2Ease of operation
If side-channel bus is connected only to RCD, then device complexity is minimized, but access to buffer registers becomes impossible
Solution Approach 1:
The patent makes the side-channel bus universal by connecting it to both the RCD and individual buffer devices. This multi-functional connection structure enables the side-channel bus to serve dual purposes: coordinating RCD operations and providing independent register access to buffers, thereby enabling buffer register access without excessive complexity.
Solution Approach 2:
The patent adds another dimension to the connection architecture by introducing side-channel bus connections that operate parallel to the main command bus. This dimensional expansion creates independent access paths to buffer registers without interfering with the primary data transmission pathway, resolving the access impossibility while maintaining reasonable complexity.
3Difficulty of detecting and measuring
If in-system access mode is enabled for debugging, then register access capability is improved, but normal system operation may be disrupted
Solution Approach 1:
The patent segments system operations into normal mode and in-system access mode through configurable register bits. This segmentation allows debugging functions to be isolated from normal data operations, enabling register access for measurement and analysis without disrupting常规 system functionality when properly configured.
Solution Approach 2:
The patent introduces dynamic mode switching capability through configurable register bits that can change system behavior between normal operation and in-system access modes. This dynamic adaptability allows the system to transition between debugging and operational states, improving debugging capability while maintaining operational stability through proper mode management.
Data Source
AI summary
During system initialization, each data buffer device and/or memory device on a memory module is configured with a unique (at least to the module) device identification number. In order to access a single device (rather than multiple buffers and/or memory devices), a target identification number is written to all of the devices using a command bus connected to all of the data buffer devices or memory devices, respectively. The devices whose respective device identification numbers do not match the target identification number are configured to ignore future command bus transactions (at least until the debug mode is turned off.) The selected device that is configured with a device identification number matching the target identification number is configured to respond to command bus transactions.