FlexRay Bus Data Validity via Header Toggle Bit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In Flexray bus data transmission, the deletion of validity bits can be incomplete before transmission, leading to undetectable errors at the receiver end, complicating the management of validity bits and potentially sending invalid data units with valid bits.
Innovation Solution
A validity date, either a toggle bit or an N-bit counter, is used to indicate the historical change in validity, allowing for reliable validation of data units by storing this information in the header segment of the data transmission block, enabling the transmission of valid data units and discarding invalid ones.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If validity bits are used to indicate data unit validity, then data validity can be tracked, but complex management of deleting validity bits is required and errors can occur if deletion is incomplete
Solution Approach 1:
The patent extracts the validity tracking function from the data unit itself by separating the validity indication (validity date in header) from the data payload. This allows the validity information to be managed independently in the header segment rather than requiring manipulation of validity bits associated with each data unit, thereby reducing complexity while maintaining reliability.
Solution Approach 2:
The patent introduces a validity date field in the header segment as an intermediary mechanism that mediates between the transmitter and receiver for validity tracking. This intermediary stores historical validity information (toggle bit or N-bit counter) that automatically indicates whether current data is valid or stale, eliminating the need for complex validity bit deletion management while ensuring reliable validity indication.
2Reliability
If validity bits are cleared before rewriting data, then invalid data units can be avoided, but undetectable errors occur if validity bits cannot be deleted in time
Solution Approach 1:
The patent performs preliminary action by pre-configuring the validity date in the header segment before data transmission. The validity date (toggle bit or N-bit counter) is set in advance to reflect the validity status of the data unit, so that when data is rewritten or transmitted, the validity information is already prepared and no time-critical deletion operations are needed, preventing undetectable errors.
Solution Approach 2:
The patent implements feedback by using the validity date as a historical record that automatically reflects the validity status. The toggle bit or N-bit counter provides continuous feedback about whether data is valid or stale based on previous transmission states, allowing the receiver to reliably determine data validity without requiring timely deletion operations.
3Reliability
If a toggle bit or N-bit counter is used for validity date, then security is enhanced with redundancy, but additional data storage is required in the header segment
Solution Approach 1:
The patent applies parameter changes by offering two different configurations for the validity date: a simple toggle bit (1-bit parameter) or an N-bit counter (multi-bit parameter). This allows the system to adjust the validity tracking mechanism based on security requirements, where the N-bit counter provides enhanced security and redundancy at the cost of additional header storage, while the toggle bit provides a lighter-weight alternative.
Data Source
Figure 1~3
Figure 2
Figure 4
AI summary
The invention relates to a method for sending a data transfer block. Said data transfer block comprises at least one data segment having a predefined number of one or several data units that are to be characterised by a validity indication and a head segment. Said method consists of the following steps: a) a data unit is written in a first area of an initial register, said first area being predefined for the data segment, from which the intermediately stored data transfer block is sent via a bus system to a predefined transmitting time point by means of a time multiplex method; b) validation data configured as a toggle bit or as a N-bit counter is written in a second area that is predefined for the head section, the respective validation data displaying the validity of the correspondingly written data unit; c) the data unit is released for transmitting the data transfer block that is intermittently stored in the initial register, after which the respective data unit and the corresponding validation data are written in the initial register; d) steps (a)-(c) are repeated until the predefined number of data units and the corresponding validation data are written or the predefined transmission point is reached; and e) the relapsed data transfer block that is intermittently stored in the initial register is sent at the transmitting time point.