KR102126671B1 - Restoring apparatus for communication error using history queue and method thereof - Google Patents

Abstract

Disclosed is an apparatus for a communication error recovery apparatus and method using a history queue. The communication error recovery apparatus using the history queue of the present invention includes a reception buffer for receiving and buffering an error message transmitted from a receiving side, a transmitting buffer for buffering a message for transmission to the receiving side, and periodically transmitting a message to the transmitting buffer. Controls the transmission of messages from the transmission message queue to the transmission buffer according to whether or not an error message has been received, and the transmission message queue, the history queue storing messages transmitted from the transmission message queue to the transmission buffer, and stored in the history queue according to the error message. It characterized in that it comprises a communication control unit for transmitting the message to the transmission buffer.

Description

Communication error recovery device and method using history queue {RESTORING APPARATUS FOR COMMUNICATION ERROR USING HISTORY QUEUE AND METHOD THEREOF}

The present invention relates to a communication error recovery apparatus and method using a history queue, and more specifically, a message in an asynchronous serial communication (UART) method in two or more processes constituting an In-Vehicle Infortainment (IVI) system. When an error occurs while transmitting/receiving, the present invention relates to a communication error recovery apparatus and method using a history queue to improve system performance by retransmitting an error message using the history queue.

In general, most recently released vehicles include a vehicle infotainment (IVI) system.

The vehicle infotainment system provides various information inside and outside the vehicle in an optimal condition for drivers and passengers, and includes two or more processors each performing a unique function. For example, infotainment (Information + Entertainment = Infortainment: a concept that combines information and entertainment) A CPU that performs a main function, an MCU that interfaces with a vehicle, and an additional processor may be further included as needed.

These two or more processors (e.g., CPU, MCU, etc.) exchange data on both sides through communication, and mainly use asynchronous serial communication (UART: Universal Asynchronous Receiver Transmitter) for technical efficiency reasons.

In this configuration, ensuring reliability of data exchange between the two processors is a very important part. However, since asynchronous serial communication is vulnerable to electrical noise due to its characteristics, data transmission error detection and recovery is performed using various methods such as parity bit check.

In order to perform such data transmission error detection and recovery, in recent years, a checksum comparison method of a data message frame unit in a higher layer is generally used due to hardware performance and technical improvement.

For example, when the MCU is the sender and the CPU is the receiver, if the checksum of the message sent from the MCU to the CPU does not match, the CPU notifies the MCU of the error and the MCU sends the error message back to the CPU. Allow data to be recovered.

However, according to the characteristics of the asynchronous communication method, the following method is used to solve this problem because the receiving side does not immediately recognize the error occurrence after sending the message.

In the first method, there is a method that waits for a certain period of time after sending the message, then transmits the next message frame and retransmits only when an error message is received while waiting. Therefore, the performance of the communication bus depends on the performance of the receiving side, and there is a problem in that the communication speed is lower than the set baud rate.

In the second method, there is a method to check whether all the transmitted messages have been received and to transmit the next message. In the case of asynchronous communication, this method is applicable only in systems that communicate at low speed or where messages are not transmitted frequently. Accordingly, there is a problem that is not suitable when a large amount of data needs to be transferred to another processor, such as a vehicle infotainment system, by being connected to a vehicle internal network.

Therefore, in order to improve this point, messages are continuously transmitted at the minimum transmission interval allowed by the system performance, and when a communication error occurs, an error message is received by receiving an error message including the frame number of the error message from the receiving side. The method of recovering the error was used by resending all messages stored after the message.

However, in this method, after the message is transmitted from the generally configured transmission message queue, the checksum error of the message is confirmed at the receiving side, and the next message is continuously transmitted while receiving the error message. A problem arises that cannot guarantee the existence of a message.

Background of the invention is disclosed in Republic of Korea Patent Publication No. 10-2009-0056465 (2009. 06. 03. published, the name of the invention: serial data communication device and method according to priority).

The present invention was created to improve the above problems, and an object of the present invention is to use a history queue when an error occurs while transmitting/receiving a message in an asynchronous serial communication method in two or more processes constituting a vehicle infotainment system. The present invention relates to a communication error recovery apparatus and method using a history queue for retransmitting an error message and a message transmitted thereafter.

Another object of the present invention, when an error message is received from the receiving side and the message is retransmitted through the history queue, the transmission message queue is controlled so that the message is not transmitted until all the messages in the history queue are transmitted, and the message in the history queue It relates to a communication error recovery apparatus and method using a history queue to delete the message existing in the hysteresis queue when all are transmitted.

A communication error recovery apparatus using a history queue according to the present invention includes: a reception buffer for receiving and buffering an error message transmitted from a receiving side; A transmission buffer buffering a message for transmission to the receiving side; A transmission message queue periodically transmitting a message to the transmission buffer; A history queue storing messages transmitted from the transmission message queue to the transmission buffer; And a communication control unit controlling message transmission from the transmission message queue to the transmission buffer according to whether the error message has been received, and transmitting the message stored in the history queue to the transmission buffer according to the error message. It characterized in that it comprises.

In the present invention, the history queue is characterized in that when the stored message is saturated, it is deleted in the order of the first stored message in a FIFO (First In First Out) method.

In the present invention, when the error message is received through the reception buffer, the communication control unit stops transmission of the message in the transmission message queue, and transmits the corresponding message according to the error message stored in the history queue to the transmission buffer. If so, it characterized in that to resume the transmission of the message in the transmission message queue.

In the present invention, when the error message is received through the reception buffer, the communication control unit transmits a message after the message corresponding to the frame number included in the error message to the transmission buffer.

In the present invention, when all messages stored in the history queue are transmitted to the transmission buffer, the communication control unit deletes all messages stored in the history queue.

A communication error recovery method using a history queue according to the present invention includes: a communication control unit storing a message transmitted from a transmission message queue to a transmission buffer in a history queue; When the communication control unit receives the error message through the reception buffer, stopping the transmission of the message from the transmission message queue; Transmitting, by the communication control unit, the corresponding message stored in the history queue to the transmission buffer according to the received error message; Determining whether all the messages stored in the history queue are transmitted to the transmission buffer by the communication control unit; And if all the messages have been transmitted to the transmission buffer, resuming the transmission of messages in the transmission message queue. It characterized in that it comprises.

In the present invention, the step of storing the message transmitted from the transmission message queue to the transmission buffer in a history queue is when the messages stored in the history queue are saturated, in the order of the first message stored in the FIFO (First In First Out) method. It characterized in that it comprises a step of deleting.

In the present invention, transmitting the corresponding message stored in the history queue to the transmission buffer according to the error message includes transmitting a message after the message corresponding to the frame number included in the error message to the transmission buffer. It is characterized by.

In the present invention, the step of determining whether all messages stored in the history queue are transmitted to the transmission buffer is characterized in that when all messages stored in the history queue are transmitted to the transmission buffer, all messages stored in the history queue are deleted. do.

A communication error recovery apparatus and method using a history queue according to the present invention, when an error occurs while transmitting/receiving a message in an asynchronous serial communication method in two or more processes constituting a vehicle infotainment system, an error occurs using the history queue By retransmitting the message and the message transmitted thereafter, loss of the message can be prevented and communication error recovery performance can be improved.

In addition, when the error message is received from the receiving side and the message is retransmitted through the history queue, the present invention controls the transmission message queue so that the message is not transmitted until all the messages in the history queue are transmitted, and all the messages in the history queue When transmitted, system performance can be secured by deleting the message existing in the hysterical queue.

1 is a block diagram showing a communication error recovery apparatus using a history queue according to an embodiment of the present invention.
2 is an exemplary view showing a structure of an MCU for an asynchronous serial communication interface between a CPU and an MCU in a vehicle infotainment system according to an embodiment of the present invention.
3 illustrates a process of transmitting and receiving a message between a receiving side and a transmitting side in a communication error recovery apparatus using a history queue according to an embodiment of the present invention.
4 is an example showing a frame format of a message transmitted to a receiving side in a communication error recovery apparatus using a history queue according to an embodiment of the present invention.
5 is an example of a frame format of an error message transmitted from a receiving side in a communication error recovery apparatus using a history queue according to an embodiment of the present invention.
6 is a flowchart illustrating an operation flow of a communication error recovery method using a history queue according to an embodiment of the present invention.

Hereinafter, a communication error recovery apparatus and method using a history queue according to an embodiment of the present invention will be described with reference to the accompanying drawings. In this process, the thickness of the lines or the size of components shown in the drawings may be exaggerated for clarity and convenience.

In addition, terms to be described later are terms defined in consideration of functions in the present invention, which may vary according to a user's or operator's intention or practice. Therefore, the definition of these terms should be made based on the contents throughout the specification.

1 is a block diagram showing a communication error recovery apparatus using a history queue according to an embodiment of the present invention, and FIG. 2 is an asynchronous serial communication interface between a CPU and an MCU in a vehicle infotainment system according to an embodiment of the present invention. It is an exemplary view showing the structure of an MCU, and FIG. 3 shows a process of transmitting and receiving a message between a receiving side and a transmitting side in a communication error recovery apparatus using a history queue according to an embodiment of the present invention.

1 to 3, a communication error recovery apparatus using a history queue according to an embodiment of the present invention includes: a reception register 10, a reception buffer 20, a reception memory unit 21, and a reception message queue 30 ), transmission register 40, transmission buffer 50, transmission memory unit 51, transmission message queue 60, history queue 70 and communication control unit 80.

When using asynchronous serial communication (UART: Universal Asynchronous Receiver Transmitter) to exchange data between two or more processors (e.g., CPU, MCU, etc.) in a vehicle infotainment (IVI: In-Vehicle Infortainment) system, As can be seen with reference to FIG. 2, the reception register 10 temporarily stores a message received from another processor, the reception buffer 20 buffering a message received through the reception register 10, and the reception buffer 20 It includes a receiving message queue 30 for periodically receiving a message, and a receiving memory unit 21 for storing the received message.

In particular, the reception buffer 20 receives and buffers an error message when a communication error occurs.

In addition, as can be seen with reference to FIG. 2, the configuration of the transmission side of the MCU buffers a message for transmission to the reception side through the transmission register 40 and the transmission register 40 that temporarily store a message to be transmitted to another processor. The transmission buffer 50, the transmission message queue 60 for periodically transmitting a message to the transmission buffer 50, the transmission memory unit 51 for storing the transmission completed message, and for storing the message transmitted to the transmission buffer 50 It includes a history queue (70).

In addition, when the stored message is saturated, the history queue 70 can maintain optimal performance at all times by deleting in the order of the first stored message in a FIFO (First In First Out) method.

At this time, the size of the history queue 70 is determined in principle to determine the optimal size through a performance verification experiment using a test code in a system load condition, but in the present invention, to the apparatus for recovering communication errors using the history queue 70 Since it is related, the method for determining the size of the history queue 70 is excluded.

In addition, the communication control unit 80 controls the transmission of a message from the transmission message queue 60 to the transmission buffer 50 according to whether an error message has been received, and transmits the corresponding message stored in the history queue 70 according to the error message. (50).

In detail, when an error message is received through the reception buffer 20, the transmission of the message from the transmission message queue 60 is stopped, and the corresponding message according to the error message stored in the history queue 70 is transmitted to the transmission buffer 50. When all are transmitted, message transmission from the transmission message queue 60 is resumed.

More specifically, the message corresponding to the frame number included in the error message received through the reception buffer 20 is searched in the history queue 70 to delete the searched message and the message transmitted before the message, and delete the message. The message after the message is transmitted to the transmission buffer 50 to be transmitted to the receiving side through the transmission buffer 50 and the transmission register 40.

At this time, when all the messages stored in the history queue 70 are transmitted to the transmission buffer 50, the communication control unit 80 resumes message transmission from the transmission message queue 60 to the transmission buffer 50, and the history queue ( 70).

That is, since all messages transmitted from the time the error occurred are retransmitted to the transmission buffer 50 through the history queue 70, the deletion of the message to ensure the performance of the history queue 70 is secured.

Referring to FIG. 3, when a checksum error of message 2 (frame 2) is confirmed while a message is being transmitted from a sending side (microcomputer) to a receiving side (CPU), an error message is received from the receiving side (CPU). , Receiving the message including the frame number (@frame 1) of the last normally received message, and allowing the history queue 70 to transmit a message corresponding to the frame number included in the error message while receiving the error message The transmitted message is also regarded as an error, and all messages after the last normally received message (frame 1) among the messages stored in the history queue 70 are retransmitted to the transmission buffer 50.

Therefore, the size of the history queue 70 is preferably such that at least the error control time (a) as shown in FIG. 3 is secured.

In addition, the history queue 70 ensures that the waiting time b is secured so that the message is retransmitted after all error messages are received.

FIG. 4 illustrates a frame format of a message transmitted from a communication error recovery apparatus using a history queue to a receiving side according to an embodiment of the present invention, and displays whether a frame number is compared with a checksum, FIG. 5 illustrates a frame format of an error message transmitted from a receiver in a communication error recovery apparatus using a history queue according to an embodiment of the present invention. Frame number, error (ERROR), and checksum (Checksum) Whether or not to compare is displayed.

As described above, the frame number in the error message is defined as the last normally received number by the receiving side.

Accordingly, the communication error recovery apparatus using a history queue according to an embodiment of the present invention uses an history queue when an error occurs while transmitting/receiving a message in an asynchronous serial communication method in two or more processes constituting a vehicle infotainment system. By retransmitting the message in which the error occurred and the message transmitted thereafter, loss of the message can be prevented and communication error recovery performance can be improved.

In addition, when an error message is received from the receiving side and the message is retransmitted through the history queue, the transmission message queue is controlled so that the message is not transmitted until all the messages in the history queue are transmitted, and when all the messages in the history queue are transmitted, the history System performance can be secured by deleting the messages in the queue.

6 is a flowchart illustrating an operation flow of a communication error recovery method using a history queue according to an embodiment of the present invention, and the specific operation of the present invention will be described with reference to this.

When the communication control unit 80 transmits a message to the transmission buffer 50 through the transmission message queue 60 periodically transmitting a message (S10), the transmitted message is stored in the history queue 70 (S20). .

At this time, when the message stored in the history queue 70 is saturated, the message is first deleted in the order of the first stored in FIFO (First In First Out) method.

Then, when the communication control unit 80 receives an error message through the reception buffer 20 (S30), the transmission of the message from the transmission message queue 60 is stopped (S40).

That is, the communication control unit 80 controls not to transmit a message from the transmission message queue 60 to the transmission buffer 50.

Then, the communication control unit 80 searches for a message corresponding to the frame number included in the error message received from the reception buffer 20 in the history queue 70 (S50).

At this time, the message retrieved in step S50 and the message transmitted before the message are deleted (S60), and the message after the deleted message is transmitted to the transmission buffer 50 (S70).

In addition, the communication control unit 80 determines whether all messages stored in the history queue 70 have been transmitted to the transmission buffer 50 (S80), and when all messages have been transmitted to the transmission buffer, all the messages in the history queue 70 Delete (S90), and resume the transmission of the message from the transmission message queue 60, so that the message is normally transmitted to the receiving side (S100).

That is, since all messages transmitted from the time the error occurred are retransmitted to the transmission buffer 50 through the history queue 70, the deletion of the message to ensure the performance of the history queue 70 is secured.

As described above, a communication error recovery method using a history queue according to an embodiment of the present invention is a history queue when an error occurs while transmitting/receiving a message in an asynchronous serial communication method in two or more processes constituting a vehicle infotainment system. By retransmitting the message in which the error occurred and the message transmitted thereafter, loss of the message can be prevented and communication error recovery performance can be improved.

In addition, when an error message is received from the receiving side and the message is retransmitted through the history queue, the transmission message queue is controlled so that the message is not transmitted until all the messages in the history queue are transmitted, and when all the messages in the history queue are transmitted, the history System performance can be secured by deleting the messages in the queue.

The present invention has been described with reference to the embodiment shown in the drawings, but this is only exemplary, and those skilled in the art to which the art belongs understand that various modifications and other equivalent embodiments are possible therefrom. will be. Therefore, the true technical protection scope of the present invention should be defined by the claims below.

10: receive register 20: receive buffer
21: receiving memory unit 30: receiving message queue
40: transmit register 50: transmit buffer
51: transmission memory unit 60: transmission message queue
70: history queue 80: communication control unit

Claims (9)

A reception buffer for receiving and buffering the error message transmitted from the reception side;
A transmission buffer buffering a message for transmission to the receiving side;
A transmission message queue periodically transmitting a message to the transmission buffer;
A history queue storing messages transmitted from the transmission message queue to the transmission buffer; And
A communication control unit controlling message transmission from the transmission message queue to the transmission buffer according to whether the error message has been received, and transmitting the message stored in the history queue to the transmission buffer according to the error message; It includes,
The communication control unit,
When the error message is received through the reception buffer, the transmission of the message from the transmission message queue is stopped, and when the corresponding message according to the error message stored in the history queue is transmitted to the transmission buffer, the transmission message queue Communication error recovery device using a history queue, characterized in that to resume the message transmission.
The method of claim 1, wherein the history queue
If the stored message is saturated, communication error recovery apparatus using a history queue, characterized in that in the order of the first message stored in FIFO (First In First Out) method.
delete According to claim 1, The communication control unit
When the error message is received through the reception buffer, a communication error recovery apparatus using a history queue, characterized in that the message corresponding to the frame number included in the error message is transmitted to the transmission buffer.
According to claim 1, The communication control unit
A communication error recovery apparatus using a history queue, characterized in that when all messages stored in the history queue are transmitted to the transmission buffer, all messages stored in the history queue are deleted.
The communication control unit storing the message transmitted from the transmission message queue to the transmission buffer in the history queue;
When the communication control unit receives the error message through the reception buffer, stopping the transmission of the message from the transmission message queue;
Transmitting, by the communication control unit, the corresponding message stored in the history queue to the transmission buffer according to the received error message;
Determining whether all the messages stored in the history queue are transmitted to the transmission buffer by the communication control unit; And
If all the messages have been transmitted to the transmission buffer, resuming the transmission of messages in the transmission message queue; Communication error recovery method using a history queue including a.
The method of claim 6, wherein the step of storing the message transmitted from the transmission message queue to the transmission buffer in a history queue is
And when the message stored in the history queue is saturated, deleting the message in the order of the first message stored in a FIFO (First In First Out) method.
The method of claim 6, wherein the step of transmitting the corresponding message stored in the history queue to the transmission buffer according to the error message is
And transmitting a message subsequent to the message corresponding to the frame number included in the error message to the transmission buffer.
The method of claim 6, wherein determining whether all messages stored in the history queue are transmitted to the transmission buffer
A communication error recovery method using a history queue, characterized in that when all messages stored in the history queue are transmitted to the transmission buffer, all messages stored in the history queue are deleted.

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