Watchdog Apparatus Using SPI Token Verification for MCU Abnormality Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing watchdog apparatuses for MCU detection rely on external feedback signals, wasting time and making it difficult to determine specific failure areas, as they do not effectively assess the stability of computational operations using software logic.
Innovation Solution
A watchdog apparatus utilizing SPI communication between a main MCU and a sub MCU, generating tokens through a pseudo random number algorithm to create time-sequential watchdog signals for determining normal or abnormal states, with specific tokens allocated to different MCU modules for initialization, decision logic, actuation, and diagnostic operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a watchdog apparatus uses external feedback signals for MCU abnormality detection, then the detection mechanism is established, but physical time is wasted and specific failure area information cannot be determined
Solution Approach 1:
The patent replaces the mechanical/physical feedback signal system with a software-based token verification system. The sub-MCU generates tokens using a pseudo-random algorithm, and the main-MCU verifies these tokens through software logic, eliminating the need for physical feedback signals and associated decision logic time.
Solution Approach 2:
The patent introduces tokens as an intermediary element between the sub-MCU and main-MCU. These tokens serve as software-based mediators that carry information about the operational state without requiring direct physical feedback signals, thus reducing time loss while maintaining detection capability.
2Reliability
If a watchdog apparatus uses external feedback signals for MCU detection, then abnormality detection is achieved, but specific information on failure areas cannot be determined
Solution Approach 1:
The patent segments the token verification process into multiple stages corresponding to different operational phases (initialization, signal input, decision logic, actuation, DTC storage). Each stage has its own token verification, allowing identification of specific failure areas when verification fails at any stage.
Solution Approach 2:
The patent uses different token types (first token through fourth token) to represent different operational states or 'colors' of the system. When a specific token verification fails, it indicates a failure in that particular operational area, providing specific failure area information.
3Measurement precision
If a watchdog apparatus is configured with additional hardware for enhanced detection, then detection accuracy improves, but device complexity increases
Solution Approach 1:
The patent replaces potential hardware additions with software-based token generation and verification algorithms. The pseudo-random token generation and multi-stage verification provide high detection accuracy without requiring additional physical components, thus avoiding increased device complexity.
Data Source
AI summary
The present invention provides a watchdog apparatus in which a main MCU and a sub MCU are connected by SPI communication, including: a token generating unit which generates a seed value and generates at least two tokens using the seed value; a watchdog signal generating unit which generates a watchdog signal corresponding to the generated token; a signal determining unit which determines whether the generated watchdog signal is in a normal state and thus provides an advantageous effect which may detect an abnormality of the MCU only using a software logic without providing an additional configuration.