Method for improving decoding robustness of MIPI A-PHY cable

Abstract

The invention discloses a method for improving decoding robustness of an MIPI A-PHY (Mobile Industry Processor Interface A-Physical Layer) cable, and belongs to the field of high-speed serial buses. The method comprises the following steps: in a process of establishing a signal link between a local end and an opposite end, periodically sending a 01 sequence with a fixed length and a fixed format by a sending end, and recording the 01 sequence as a first sequence; and in the stage of establishing the double-end signal link, the receiving end continuously detects the received code stream, and when the receiving end continuously detects that the number of times of the first sequence reaches a preset threshold value thresholdA, the double-end signal link work is completed. Compared with a cable link algorithm which does not limit adjacent detection intervals, the algorithm provided by the invention has the advantages that the cable link judgment standard is improved, the occurrence of misrecognition caused by poor signal quality is effectively avoided, a foundation is laid for subsequent decoding operation, the credibility of real data after decoding is improved, the realizability on a hardware circuit is high, and the method is suitable for popularization and application. The method has high configurability, and improves the degree of adaptation to different link detection environments.

Description

Technical Field

[0001] This invention relates to the field of high-speed serial bus technology, and in particular to a method for improving the robustness of MIPI A-PHY cable decoding. Background Technology

[0002] At the MIPI (Mobile Industry Processor Interface) A-PHY (Automobile PHY) signal receiver, current cable adaptive decoding algorithms have a certain probability of producing a series of erroneous sequences when the initial signal quality is poor. This can cause the signal receiver to misidentify the erroneous sequence as the correct one, or even mistakenly detect that the cable is inserted in reverse.

[0003] To enhance the reliability of the decoding process at the MIPI A-PHY signal receiver, a feasible solution is urgently needed to reduce the occurrence of misidentification by the receiver due to poor signal quality, thereby improving the robustness of the MIPI A-PHY receiver's decoding operation. Summary of the Invention

[0004] The purpose of this invention is to provide a method for improving the robustness of MIPI A-PHY cable decoding, so as to solve the problems in the background art.

[0005] To address the aforementioned technical problems, this invention provides a method for improving the robustness of MIPI A-PHY cable decoding, comprising the following steps: During the process of establishing a signal link between the local end and the peer end, the transmitting end periodically sends a 01 sequence of fixed length and fixed format, which is denoted as the first sequence; During the establishment of the dual-end signal link, the receiver continuously detects the received bitstream. When the number of times the receiver continuously detects the first sequence reaches the preset threshold_A, the dual-end signal link operation is completed.

[0006] In one embodiment, the method further includes: during the identification of the first sequence, setting a minimum sequence detection interval T for two adjacent identifications. LMT-MIN and maximum sequence detection interval T LMT-MAX Simultaneously, a sequence detection interval counter and a first sequence repetition counter are established; among them, The sequence detection interval counter is responsible for recording the interval between two adjacent identifications of the first sequence, and the first sequence repetition counter is responsible for recording the number of times the receiver detects the first sequence. After detecting the first sequence, only in T LMT-MIN To T LMT-MAXIf the first sequence is detected again within the time frame, it is considered valid, and the repeatability counter of the first sequence needs to be incremented by 1. If it is less than T LMT-MIN Or greater than T LMT-MAX If the first sequence is detected again within the specified time frame, it is determined that the first sequence detected this time is invalid, and the first sequence repetition counter and the sequence detection interval counter need to be reset. When an invalid first sequence is detected, it is determined that this is the first first sequence seen during the linking process, and the state machine is allowed to start the detection again.

[0007] In one implementation, if the first sequence detected for the first time is a bit error, it is not considered a correct first sequence; when the second sequence detected is identified as an invalid sequence, the second sequence is treated as the first sequence detected, until the sequence detected when the signal quality is stable is definitely a correct sequence.

[0008] In one implementation, the minimum sequence detection interval T LMT-MIN The maximum sequence detection interval T LMT-MAX The threshold_A is dynamically adjusted based on the actual MIPI A-PHY link signal interference, and both are configured by registers.

[0009] The present invention provides a method for improving the robustness of MIPI A-PHY cable decoding, which has the following beneficial effects: (1) Compared with the cable linking algorithm that does not limit the adjacent detection interval, the algorithm provided by the present invention improves the cable linking judgment standard, effectively avoids misidentification caused by poor signal quality, lays the groundwork for subsequent decoding operations, and improves the credibility of the real data after decoding. (2) The cable decoding algorithm provided by the present invention is relatively simple, has high feasibility in hardware circuits, has high configurability, and improves adaptability to different link detection environments. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of the first sequence detector provided by the present invention in the A-PHY system.

[0011] Figure 2 This is a schematic diagram of the first sequence and sequence detection interval provided by the present invention.

[0012] Figure 3 This is a schematic diagram of the algorithm framework provided by the present invention for improving the robustness of MIPI A-PHY cable decoding. Detailed Implementation

[0013] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a method for improving the robustness of MIPI A-PHY cable decoding proposed in this invention. The advantages and features of this invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this invention.

[0014] During the establishment of the signal link between the local and peer ends in MIPI A-PHY, the transmitting end (TX, Transmitter) will periodically send a 01 sequence of fixed length and fixed format at a certain stage, which is referred to as the first sequence. During the establishment of the two-end signal link, the MIPI A-PHY signal receiving end (RX, Receiver) will continuously detect the received bit stream. When the number of times the receiving end (RX) continuously detects the first sequence reaches the preset threshold threshold_A, it will consider the two-end signal link to be completed.

[0015] During the identification of the first sequence, a minimum sequence detection interval T is set for two adjacent identifications. LMT-MIN and maximum sequence detection interval T LMT-MAX Simultaneously, a sequence detection interval counter and a first sequence repetition counter are set up. The sequence detection interval counter is responsible for recording the interval between two adjacent identifications of the first sequence, and the first sequence repetition counter is responsible for recording the number of times the receiver (RX) detects the first sequence.

[0016] After detecting the first sequence, only in T LMT-MIN To T LMT-MAX If the first sequence is detected again within the time range, the first sequence detected this time is considered valid, and the first sequence repetition counter needs to be incremented by 1.

[0017] If it is less than T LMT-MIN Or greater than T LMT-MAX If the first sequence is detected again within the specified time range, the first sequence detected this time is considered invalid, and the first sequence repetition counter and the sequence detection interval counter need to be reset.

[0018] When an invalid first sequence is detected, it will be considered the first first sequence seen during the linking process, causing the state machine to restart the detection.

[0019] The T mentioned above LMT-MIN T LMT-MAX Both threshold_A and threshold can be dynamically adjusted according to the actual MIPI A-PHY link signal interference, and can be configured by registers.

[0020] This embodiment uses the A-PHY system as an example to describe the invention in detail. It is worth noting that the application scenarios of the invention include, but are not limited to, the A-PHY system.

[0021] like Figure 1 This is a schematic diagram showing the location of the first sequence detector in the MIPI A-PHY system. Figure 2 This is a schematic diagram of the first sequence and the sequence detection interval. Figure 2 Taking the first sequence as "00111100" as an example, after the system powers on, the MIPI A-PHY receiver (RX) will start a sequence detection interval counter after detecting the first sequence for the first time. It will continue to counter until the first sequence is detected again, at which point it will determine whether the sequence detection interval meets the specified requirements. In cases where the initial signal quality is poor, there is a certain probability that this will occur. Figure 2 The bit data marked by the middle triangle was misidentified as 1 when it was 0, which in turn led to misidentification as the first sequence.

[0022] like Figure 3 As shown, after the system is powered on, the MIPI A-PHY data link is started. When the MIPI A-PHY receiver (RX) recognizes the first sequence, the sequence detection interval counter immediately starts counting. Until the MIPI A-PHY receiver (RX) detects the first sequence again in the data link, the first sequence repetition counter increments by 1, and simultaneously checks whether the value of the sequence detection interval counter is within the preset T. LMT-MIN and T LMT-MAX between: 1. If the sequence detection interval counter is located at T LMT-MIN and T LMT-MAX Between these intervals, the sequence detection interval counter is cleared and the next round of counting begins. 2. If the sequence detection interval counter is less than T LMT-MIN Or greater than T LMT-MAX If the sequence detection interval counter and the first sequence repetition counter are both cleared to zero, the first sequence identified by the receiver will be considered an invalid sequence.

[0023] Since the signal quality on the data link may be poor when powered on, the first sequence detected may also be an error and should not be regarded as the correct first sequence. Therefore, when the second sequence detected is identified as an invalid sequence, the second sequence is regarded as the first sequence detected, and so on, until the sequence detected when the signal quality is stable is definitely the correct sequence.

[0024] When the sequence detection interval counter is at T LMT-MIN and T LMT-MAXBetween these steps, and after resetting the sequence detection interval counter to zero and recounting, it is determined whether the first sequence repetition counter is greater than the preset threshold_A: 1. If the first sequence repetition counter is greater than the preset threshold, the sequence detection work ends and the data path connection is declared complete; 2. Otherwise, continue to check if the subsequent sequence detection interval meets the preset T. LMT-MIN and T LMT-MAX The first sequence between them is processed until the repetition counter of the first sequence is greater than a preset threshold, at which point the data path link is declared complete.

[0025] The present invention aims to improve the reliability of the data path linking process between the local and remote ends, and reduce the probability that the receiving end will erroneously detect the first sequence due to data signal quality problems during the linking process, resulting in premature data path linking.

[0026] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A method for improving the robustness of MIPI A-PHY cable decoding, characterized in that, Includes the following steps: During the process of establishing a signal link between the local end and the peer end, the transmitting end periodically sends a 01 sequence of fixed length and fixed format, which is denoted as the first sequence; During the establishment of the dual-end signal link, the receiver continuously detects the received bitstream. When the number of times the receiver continuously detects the first sequence reaches the preset threshold_A, the dual-end signal link operation is completed.

2. The method for improving the robustness of MIPI A-PHY cable decoding as described in claim 1, characterized in that, The method further includes: during the identification of the first sequence, setting a minimum sequence detection interval T for two adjacent identifications. LMT-MIN and maximum sequence detection interval T LMT-MAX Simultaneously, a sequence detection interval counter and a first sequence repetition counter are established; among them, The sequence detection interval counter is responsible for recording the interval between two adjacent identifications of the first sequence, and the first sequence repetition counter is responsible for recording the number of times the receiver detects the first sequence. After detecting the first sequence, only in T LMT-MIN To T LMT-MAX If the first sequence is detected again within the time frame, it is considered valid, and the repeatability counter of the first sequence needs to be incremented by 1. If it is less than T LMT-MIN Or greater than T LMT-MAX If the first sequence is detected again within the specified time frame, it is determined that the first sequence detected this time is invalid, and the first sequence repetition counter and the sequence detection interval counter need to be reset. When an invalid first sequence is detected, it is determined that this is the first first sequence seen during the linking process, and the state machine is allowed to start the detection again.

3. The method for improving the robustness of MIPI A-PHY cable decoding as described in claim 2, characterized in that, If the first sequence detected is an error, it is not considered a correct first sequence. When the second sequence detected is identified as an invalid sequence, the second sequence is treated as the first sequence detected, until the sequence detected when the signal quality is stable is definitely a correct sequence.

4. The method for improving the robustness of MIPI A-PHY cable decoding as described in claim 2, characterized in that, The minimum sequence detection interval T LMT-MIN The maximum sequence detection interval T LMT-MAX The threshold_A is dynamically adjusted based on the actual MIPIA-PHY link signal interference, and both are configured by registers.

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