KR20140048534A - Method for supporting real time communication with test equipments - Google Patents

Abstract

An inspection apparatus capable of real-time communication and a method for supporting the real-time communication of the same are disclosed. The method for supporting the real-time communication of the inspection apparatus according to the present invention comprises the steps of: communicating data with an external device using MIL-STD-1553B communication for checking a performance of an embedded system; providing a real-time in the communication step by using a real-time transplantation kernel which generates a periodic timer interrupt; and periodically invoking the data communication by the communication step. [Reference numerals] (110) Communications unit; (120) Real-time providing unit; (130) Calling unit

Description

[0001] The present invention relates to a method for real-

The present invention relates to a check device capable of real-time communication and a real-time communication support method thereof, and more particularly, to a check device capable of real-time communication capable of providing real-time communication equipment operating in a Windows environment, And a communication support method.

Embedded systems developed in military and aerospace must perform functional tests, or acceptance tests, to verify the performance of the equipment before it is actually used. In order to verify the performance of the embedded system, it is necessary to inspect the embedded system. In particular, inspection equipment used in guided weapon systems should be capable of acquiring and evaluating data in real time, which requires accurate data collection and real-time data communication.

In general, the inspection equipment is based on the x86 architecture provided by Intel and uses the Windows operating system to provide development convenience. However, since the Windows operating system is not a real-time operating system and communicates using a multimedia timer provided by Windows, it does not guarantee real-time communication when communication is performed at intervals of 10 ms or less. Even if it provides real- There is a problem that communication synchronization can not be achieved because the kernel can not be modified for synchronization.

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the above-mentioned problems, and provides a real-time communication device capable of real-time communication that can reduce the development cost of a product, and a real- .

According to another aspect of the present invention, there is provided a checking apparatus for checking the performance of an embedded system, the checking apparatus comprising: a communication unit for transmitting and receiving data with an external device; A real-time sex creator that provides real-time performance to a communication unit using a real-time porting kernel that generates a periodic timer interrupt; And a calling unit for periodically calling the communication unit to connect to the real-time sex-free service.

The real-time agent and call unit can operate in real-time implant kernel (RTiK) operating mode.

Here, the real-time property provider can provide real-time performance by controlling the Local APIC of the x86-based hardware platform through the hardware abstraction layer (HAL).

In addition, the caller can perform a defined operation on threads operating at the Windows user level to ensure periodic operation.

In addition, the communication unit may perform real-time communication using at least one of a polling method and a double buffer.

At this time, it is preferable that the communication unit performs communication using MIL-STD-1553B communication.

A real-time communication support method for realizing the above-mentioned object includes the steps of: communicating data with an external device, in a real-time communication supporting method of a check device for checking the performance of an embedded system; Providing a real-time property to a communication step using a real-time porting kernel that generates a periodic timer interrupt; And a step of periodically calling the data communication by the communication step.

Here, the real-time property providing step and the calling step may operate according to RTiK (Real-Time Implant Kernel) operation method.

The real-time provisioning step can provide real-time performance by controlling the Local APIC of the x86-based hardware platform through the Hardware Abstraction Layer (HAL).

In addition, the calling step can guarantee the periodic operation by performing the operation defined in the threads operating at the Windows user level.

In addition, the communication step may perform real-time communication using at least one of a polling method and a double buffer.

At this time, it is preferable that the communication step performs communication using MIL-STD-1553B communication.

According to the present invention, it is possible to provide a real-time property to a communication device operating in a Windows environment, and to reduce a development cost of a product.

Also, according to the present invention, by using the MTL-STD-1553B communication, the error occurrence rate in the checking apparatus can be minimized, thereby solving the synchronization problem between these types of computers.

1 is a schematic view of a checking apparatus according to an embodiment of the present invention.
2 is a flowchart illustrating an operation of the RTiK in a multicore environment.
3 is a diagram illustrating an operation of the event-based RTiK.
4 is a diagram showing a communication structure of the checking apparatus.
5 is a diagram showing a real-time communication structure using the polling method.
6 is a diagram illustrating a real-time communication structure using a polling method and a double buffer.
7 is a diagram showing the overall structure of MIL-STD-1553B communication.
FIG. 8 is a diagram showing a BC program structure of MIL-STD-1553B in which a TX command and an RX command are created in a cycle thread of RTiK.
9 is a diagram showing an RT program structure of MIL-STD-1553B using a double buffer.
10 is a diagram illustrating an experimental environment configured to verify a real-time operation.
11 is a view showing an example of equipment for the experimental environment of FIG.
12 is a diagram showing an example of a 2 ms measurement of a communication cycle using RTiK.
13 is a diagram showing an example of confirmation of communication data of RTiK.
14 is a diagram showing another example of the measurement of the communication period 2 ms using RTiK.
15 is a diagram showing another example of confirmation of communication data of RTiK.
FIG. 16 is a diagram illustrating 10 communication cycles with 2 ms measurement using RTiK and work.
17 is a diagram showing an example of communication data confirmation when a workload is applied.
18 is a diagram showing the results of 2 ms, 5 ms, and 10 ms test results when a workload is applied.
19 is a flowchart illustrating a method for supporting real-time communication according to an embodiment of the present invention.

Hereinafter, a checking apparatus capable of real-time communication according to an embodiment of the present invention and a real-time communication supporting method thereof will be described in detail with reference to the accompanying drawings.

Inspection equipment to check the performance of the embedded system provides real-time property to Windows using real-time extension (RTX), INtime and RTiK (Real-Time implant Kernel) can do.

IntervalZero's RTX is an extension of the real-time operating system that allows real-time control of Windows XP and Windows 7, allowing most developers to take advantage of existing Windows with RTX in a familiar and convenient Windows environment . In other words, RTX is not a pure real-time operating system, but software that compensates for limitations such as real-time performance by making full use of advantages of Windows popular and rich GUI library. These RTXs are currently used in many industries, including defense, aerospace, instrumentation, simulation, and medical devices.

INtime is Intel's x86 / CPU-specific real-time system software using the iRMX kernel developed by Intel Corporation. INtime adds INtime to the control and measurement system using Windows XP / Windows 2000 as a platform, allowing INtime to handle processing that requires real-time performance on the system. It provides higher reliability and precise real-time performance while maintaining Windows flexibility. Can be supplemented. INtime is a real-time operating system that cooperates with industrial computers, x86 board computers, and general-purpose Windows operating systems. It is a real-time operating system that runs simultaneously with Windows on the same hardware. Therefore, Windows installed with INtime becomes a multi-kernel system with two kernels, which operates using two virtual CPUs.

However, the commercial third parties, INtime and RTX, are capable of real-time communication only when the designated communication equipment is used, and commercial solutions such as RTX and INtime have expensive commercial usage fees, There is a problem that a lot of development costs are incurred.

In order to solve this problem, a checking apparatus 100 according to an embodiment of the present invention checks the performance of an embedded system. As shown in FIG. 1, the checking apparatus 100 includes a communication unit 110 for transmitting / receiving data with an external device, A real-time sex creator 120 for providing a real-time property to the communication unit 110 using a real-time porting kernel that generates a timer interrupt, and a call for periodically calling the communication unit 110 to connect to the real- (130).

Here, the real-time sex creator 120 and the calling unit 130 may operate in the RTiK operation mode.

RTiK, implemented as a Windows device driver, runs at the kernel level and has access to hardware resources and Windows kernel. In order to support real - time performance, real - time performance is provided through control of Local APIC of x86 based hardware platform through Hardware Abstraction Layer (HAL). This ensures periodic operation by generating timer interrupts independent of Windows through the control of registers associated with the Local APIC timer on x86 hardware.

2 is a diagram illustrating an overall operation of the RTiK operating in a multicore environment.

As shown in FIG. 2, in the case of a system having two CPUs, each processor has its own local APIC, and in case of RTiK-MP, it provides real-time performance using AP (Application Processor)'s Local APIC.

When a local APIC timer of the AP occurs, a timer handler is executed using the IDT (Interrupt Descriptor Table) of the AP. The handler executed registers the DPC in the DPC (Deferred Procedure Call) queue of each processor. When the execution of the interrupt is completed and the IRQL value reaches the DPC Dispatch level, the registered DPCs are processed in the DPC routine.

RTiK provides a way to support real-time behavior for threads running at the Windows user level. As shown in FIG. 3, when a user creates a real-time thread through an API provided by RTiK and writes an execution code, the generated real-time thread waits for a signal transmitted from the kernel level. When Siganl is received from the kernel level, it performs periodic operations by performing the tasks defined in the real-time thread.

Windows-based inspection equipment should be able to acquire and evaluate data in real-time for acceptance testing of the developed new weapon. Acceptance tests should periodically acquire and deliver data and evaluate the acquired data through a specific algorithm. In particular, real-time capability is required to acquire and deliver data periodically. However, since the inspection equipment is connected to another computer with a communication device to transmit and receive data, and there is no way to notify that data transmission or reception has been performed when data is transmitted between the inspection equipment and another type of computer, Communication can not be done. If synchronous communication is not possible, periodic communication for acceptance test can not be performed because the receiving computer does not receive data in real time even if data is transmitted in real time from the inspection equipment. In order to solve such a problem, the checking apparatus 100 according to the embodiment of the present invention provides a method for providing real-time property in the communication structure as shown in FIG.

The communication unit 110 can perform real-time communication using a polling method.

Communication between the Windows-based inspection equipment and other computers connected to the communication device can not perform synchronous communication between these types of computers. Therefore, it is necessary to provide real-time properties to the transmitting side and the receiving side respectively.

RTiK is used for real-time data communication by providing real-time property to Windows-based inspection equipment. RTiK should be ported to target PC as well as inspection equipment. Transmit and receive operate as periodic threads of RTiK, respectively, and transmission and reception are performed at set intervals. 5 is a real-time communication structure of the inspection equipment using the polling method.

In real-time communication using RTiK, when data is sent by asynchronous communication, it is not sending data and receiving data, but it sets period of RTiK on transmission side and periodically transmits it. On the receiving side, The data is read from the buffer by using the polling method, so that periodic communication is performed. However, when polling method is used, data loss occurs when errors occur in transmission and reception period, and period should be set considering transmission time and reception time.

In the method using the polling method, since a data loss occurs when a transmission error occurs in a transmission side and a reception side, a communication error occurs due to an error that activates the RTiK during high-speed communication. In case that all data is not received at the time of receiving, new data may be written to the buffer and erroneous data may be received. This problem can be solved by using two data buffers. 6 is a diagram illustrating a real-time communication structure using a polling method and a double buffer.

The method of FIG. 6 is a structure using two data buffers in a communication structure using a polling method after transplanting RTiK to a portable inspection device and a target PC, respectively. By setting the cycle of RTiK in the inspection device, 1, and then transmits the data to the buffer 2. When receiving data from the target PC, buffer 1 receives data first, and buffer 2 receives data in the next cycle. In such a structure, after the data transmission is performed in the inspection equipment, it is possible to solve the problem of receiving the wrong data by transmitting the data to the same buffer without receiving the data due to the error of the cycle. Also, it is possible to solve the data loss problem due to the activation error of RTiK in high-speed communication.

Inspection equipment used for performance verification in guided weapon systems needs to acquire and evaluate data in real time, and since reliability is required, communication using MIL-STD-1553B is widely used.

The inspection apparatus 100 according to an embodiment of the present invention supports a real-time communication method using MIL-STD-1553B to test a real-time communication method for military inspection equipment.

The bus of MIL-STD-1553B is operated for the purpose of system integration of aviation electronic equipment (weapons systems) in an aircraft. When buses of different kinds are installed, communication protocol To communicate using the message transmission method. The data bus of MIL-STD-1553B is a standard for industrial, military, and space data buses and is used in fields requiring high reliability.

7 is a diagram showing the overall structure of MIL-STD-1553B communication.

BC (Bus Controller) controls all data flow of information transmission through data bus, and RT (Remote Terminal) is controlled by BC. Monitoring (MT) monitors all messages communicated on the data bus. In the communication method of MIL-STD-1553B, Command Word and Data Word are transmitted to transmit data from BC to RT. After validating Command Word, RT receives the Status Word and Data Word . This ensures reliable communication.

BC of MIL-STD-1553B controls the flow of all data when transmitting information through the data bus, and communication is performed by transmitting TX and RX commands to RT in BC. The TX command is used to transmit data from the RT to the BC, and the RX command is used to receive data sent from the RT on the RT. Therefore, TX command and RX command must be created and operated in the RTiK cycle thread for real-time communication.

FIG. 8 is a diagram showing a BC program structure of MIL-STD-1553B in which a TX command and an RX command are created in a cycle thread of RTiK. In the program structure of FIG. 8, after removing the RX link, it is confirmed that the TX link is connected to receive the data sent from the RT, the TX link is removed, and then the RX link is connected to transmit the data to the RT. This is because, if TX and RX Link are connected together, data loss is caused by transmitting RX command immediately after the TX command is completed within the set period. For example, when TX link and RX link are connected together to operate at 2ms, if 1.2ms is required for TX command, RX command for next command takes 0.8ms. This means that transmission of data by RX command does not work periodically because TX sends RX command immediately at the end of command, and it is possible to set the cycle of TX and RX command when operating at set cycle Since there is no RT, there is an error in setting cycle of RT and data loss occurs.

To solve this problem, after releasing the RX Link, connect the TX Link to receive the data, release the TX Link, connect the RX Link to transmit data, and transmit and receive data periodically Respectively.

RT of MIL-STD-1553B transmits the data in the buffer when receiving the TX command from the BC. To send the data incremented by one from the previous data, the data must be written in the buffer at the same cycle as the cycle set in BC. However, data may be lost due to RTiK activation errors implanted in BC and RT. To solve this problem, a double buffer is used in the present invention.

9 is a diagram showing an RT program structure of MIL-STD-1553B using a double buffer. The structure of the RT program is to find the data buffer to be transmitted and to fill the buffer 1 when the data of the buffer 0 is being transmitted and to fill the buffer 0 when the data of the buffer 1 is being transmitted. At this time, the active buffer pointer is used to find the buffer being transmitted. If the active buffer pointer is the same as the previous active buffer pointer, no data is filled in the buffer. In this way, it is possible to perform periodic communication without loss of data even during data communication of at least 2 ms.

The experimental environment configured to verify the real-time operation of the device used for communication of the inspection equipment is shown in FIGS. 10 and 11. FIG.

As shown in FIGS. 10 and 11, RTiK was implanted to provide real-time communication to the inspection equipment and used to provide real-time performance to the MIL-STD-1553B communication. In order to check the communication cycle of MIL-STD-1553B, I / O module was used to output the data to the oscilloscope. In order to verify the accuracy of data, it was confirmed that all 32 Word data transmitted using MT PC were transmitted without abnormality .

In the experimental method, TX and RX commands are transmitted using the BC API in the user area of RTiK which provides real - time property, and the data buffer is updated periodically using RTiK in the RT to transmit the data when TX command is received. In addition, the data received by the TX command in the BC is read and transmitted to the RT in the RX command. However, because there is an error in activating RTiK in BC and RT, the RT receives the TX command in the buffer while updating the data in the buffer, and the data is sent, failing to guarantee the reliability of the data. Therefore, in order to guarantee the reliability, when two buffers are placed in the RT to transmit data to one buffer, the data in the other buffer is updated. Thus, periodic communication without loss of data in MIL-STD-1553B communication . In the case of the communication cycle measurement, the period was measured by setting the periods of BC and RT to 2 ms, 5 ms, and 15 ms, respectively. Likewise, we compared the performance of RTiK and RTX by analyzing performance using RTX in the same environment.

FIG. 12 is a result of measuring the cycle using the oscilloscope by setting the MIL-STD-1553B communication cycle to 2 ms, which is the minimum cycle, after RTiK is implanted in the inspection equipment. To measure the period with an oscilloscope, a signal of 1 and 0 was sent in 2 ms. In the oscilloscope, the period of receiving two signals is measured. If you divide this by 2, you can see the period when the signal is sent as 1 and the period when the signal is sent as 0. As shown in FIG. 12, it can be confirmed that the data is transmitted with an error of about 1.5% when the data is transmitted.

To verify the accuracy of the transmitted data, the data was verified using MT which can check the data passing on the MIL-STD-1553B bus. FIG. 13 is a diagram showing communication data set by setting a minimum period of 2 ms in which communication can be performed. As shown in the figure, when the TX command is sent from the BC to the RT, the data is sent from the RT to the BC. At this time, RT checks the buffer that is not transmitted periodically and increases the data of 32 words in size by one. After transmitting the data from RT to BC with TX command, the data received from RT through RX command is transmitted again from BC to RT. As shown in the figure, it can be seen that data increased by 1 without loss of data.

14 is a result measurement screen using RTX in the same environment. As shown in the figure, RTX operates with an error of 1%. This shows that RTiK and RTX have the same performance. Also, as shown in FIG. 15, it can be seen that the RTX is also transmitted without data loss in the MIL-STD-1553B communication.

FIGS. 16 and 17 are views showing results of measurement of communication cycle and data when the number of workloads running in Windows increases. As can be seen from FIGS. 16 and 17, it can be seen that the system operates without deviating much from the set period in the minimum period of 2 ms operation. The workload is a Windows process that repeats the While statement infinitely. As Windows processes become larger, Windows does not affect the communication thread even if the interrupt latency is increased due to the interrupt for scheduling. This means that the communication thread provides real-time performance regardless of the workload.

FIG. 18 is a table showing the cycle variation according to the number of workloads simultaneously operating when the communication cycle is set to 2 ms, 5 ms, and 10 ms. As shown in the table, the MIL-STD-1553B communication using RTiK and RTX is not affected by the workload and can be confirmed to operate normally without any error in the set period.

The following experimental results show that RTiK polling method and double buffer communication enable real-time communication for military inspection equipment.

Recently, as the technology for communication network in military equipment and aviation has developed remarkably, accuracy of data collection and real-time data communication are required. In particular, researches are being actively carried out to provide real-time communication to the inspection equipment used in the performance verification of newly developed weapons. However, there is a problem that it is difficult to provide real-time communication because the inspection equipment is configured based on Windows, which is a general-purpose operating system that does not provide real-time property. In order to solve this problem, RTX and INtime are used to provide real-time performance. However, in the case of a third party, there is a problem of increasing the development cost due to high purchase cost and current usage fee. Therefore, it is necessary to study to provide real - time property to the communication device used in the inspection equipment using the RTiK developed in the past.

In the present invention, in order to provide real-time communication in the communication of the inspection apparatus, a method of providing real-time communication to the inspection equipment using a periodic polling method using RTiK, and a method of providing a real- We have designed a method that can prevent data loss due to errors and provide real - time performance. To test this, we used MIL-STD-1553B communication equipment which is widely used in the field which requires extreme reliability in Windows-based inspection equipment. We provide real-time inspection equipment and target PC to transmit data periodically and polling method And real-time communication by reading data from the data buffer. In addition, we verified that RTiK - based polling method and double buffer can provide real - time performance for communication of inspection equipment through performance verification.

FIG. 19 is a flowchart illustrating a method for supporting real-time communication of a checking apparatus according to an embodiment of the present invention. Referring to the drawings, a method for supporting real-time communication of a checking apparatus 100 includes a step (S110) of communicating data with an external apparatus, in a real-time communication supporting method of a checking apparatus for checking the performance of an embedded system. (S120) of providing a real-time property to a communication step using a real-time porting kernel that generates a periodic timer interrupt; And a step (S 130) of periodically calling data communication by the communication step.

Here, the real-time property providing step and the calling step may operate according to RTiK (Real-Time Implant Kernel) operation method.

The real-time provisioning step can provide real-time performance by controlling the Local APIC of the x86-based hardware platform through the Hardware Abstraction Layer (HAL).

In addition, the calling step can guarantee the periodic operation by performing the operation defined in the threads operating at the Windows user level.

In addition, the communication step may perform real-time communication using at least one of a polling method and a double buffer.

At this time, it is preferable that the communication step performs communication using MIL-STD-1553B communication.

Claims (5)

A method for supporting real-time communication of a checking apparatus for checking the performance of an embedded system,
Communicating data with an external device using MIL-STD-1553B communication;
Providing a real-time property to the communication step using a real-time porting kernel that generates a periodic timer interrupt; And
Periodically calling the data communication by the communication step
And a controller for controlling the real-time communication of the inspection device. The method of claim 1,
The real-time communication providing step and the calling step is a real-time communication support method of the inspection device, characterized in that operating in the RTiK (Real-Time implant Kernel) operating method. 3. The method of claim 2,
Wherein the real-time property providing step provides real-time property through control of a local APIC of an x86-based hardware platform through a hardware abstraction layer (HAL). 3. The method of claim 2,
Wherein the calling step ensures a periodic operation by performing a task defined in threads running at a Windows user level. The method according to claim 3 or 4,
Wherein the communication step performs real-time communication using at least one of a polling method and a double buffer.

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