Cartesian Addressing for Low-Latency Device Enumeration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional device enumeration techniques in integrated circuits, such as fuse-based methods and I/O bootstrapping, are inefficient and increase die area and packaging costs, while firmware solutions complicate the system.
Innovation Solution
A point-to-point (P2P) link-based enumeration technique that assigns unique node IDs to each device, eliminating the need for pre-assignment of addresses and allowing for bit-optimized Cartesian addressing without routing tables, reducing complexity and costs.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If fuse-based enumeration is used to identify device configurations, then device identification is achieved, but die area is increased
Solution Approach 1:
The patent extracts the enumeration function from dedicated hardware components (fuses, I/O pins) and implements it through software-based protocols using existing communication interfaces. This removes the need for additional physical enumeration hardware, thereby reducing die area while maintaining device identification capability
Solution Approach 2:
The patent makes existing communication interfaces (I2C, SPI, UART) serve dual purposes: both data communication and device enumeration. By making these interfaces universal for multiple functions, no dedicated enumeration hardware is needed, reducing die area while achieving precise device identification
2Measurement precision
If I/O bootstrapping is used for enumeration, then device identification is achieved, but packaging costs and component requirements increase
Solution Approach 1:
The patent enables existing I/O pins to serve dual purposes: general-purpose I/O operations and enumeration functions. By programming pins to boot into enumeration mode temporarily, the same pins are used for both data I/O and device identification, eliminating the need for dedicated enumeration pins and reducing packaging complexity
Solution Approach 2:
The patent implements preliminary configuration where devices are pre-programmed with enumeration capabilities during manufacturing. The devices automatically enter enumeration mode upon power-up before normal operation, performing the identification function in advance using existing I/O infrastructure without additional components
3Measurement precision
If firmware-based enumeration is used, then device identification is achieved, but die area and system complexity increase
Solution Approach 1:
The patent implements a layered enumeration approach where basic device identification is achieved through simple protocols, and only additional detailed enumeration is performed when needed. This partial action approach keeps the base system simple while allowing optional complexity for advanced enumeration requirements
Solution Approach 2:
The patent implements self-service enumeration where devices automatically provide their identification information through standardized protocols without requiring complex host controller intervention. The enumeration process is autonomous and uses existing communication infrastructure, reducing overall system complexity
4Reliability
If conventional enumeration protocols are used, then device communication is established, but communication latency increases
Solution Approach 1:
The patent performs device enumeration and address assignment as a preliminary action during system initialization or boot-up phase. Once enumeration is complete, devices use their assigned addresses for direct communication without repeated enumeration overhead, significantly reducing operational communication latency while maintaining reliable device establishment
Data Source
AI summary
An enumeration technique is provided that requires no pre-assignment of addresses to slave devices connected through P2P links to a host device. With regard to any P2P link between devices, one device has a master interface and the remaining device has a slave interface. To distinguish between the master and slave interfaces, a master/slave status bit may be used. Each P2P link has a link ID that may be concatenated with the status bit for a corresponding interface (slave or master) to form a node ID. The host device receives a unique concatenated address from each slave device that represents a concatenation of the node ID for the slave and the node ID for any intervening interfaces between the slave device and the host device. The host device then assigns a unique Cartesian address to each slave device.