A high-speed communication backplane with redundant controller and communication method thereof

Abstract

The present invention relates to a high-speed communication backplane with redundant controllers and a communication method thereof. The backplane communication includes a main controller card 1, a main controller card 2, a plurality of IO boards, and a communication backplane with a plurality of high-speed connectors. A high-speed LVDS communication interface is used between two main controller cards for data hot standby to realize the redundancy of the main controller card. The main controller card and the IO board are interconnected through two high-speed MLVDS communication interfaces to realize the redundancy of the backplane communication bus. During periodic communication, the bus communication protocol of the present invention supports an optimized sequence combination working mode, and the high-speed device and the slow device reasonably configure the scheduling time of each IO board, reduce the communication idle time, and improve the bus data exchange speed. The bus communication protocol message includes the destination address, source address, type, timestamp, status bit, data length, data, CRC check and the like. The message content can be used for identity verification, time synchronization, status monitoring, data verification, and ensure the security and reliability of the backplane communication data.

Description

Technical Field

[0001] The present invention relates to the field of high-speed backplane bus communication in industrial control systems, and specifically provides a high-speed communication backplane with a redundant controller. The backplane ensures the reliability, security and high-speed data exchange of system communication through a hardware redundancy mechanism and a bus communication protocol. Background Art

[0002] In industrial control systems, the communication backplane is responsible for connecting multiple IO boards, as well as at least one main controller card and power card. The physical layer generally uses differential serial communication or parallel communication. Serial communication mostly uses CAN and RS485 bus communication solutions. A single bus does not exceed 10Mbps, and the data exchange speed is low. The data exchange speed of parallel communication is proportional to the line width. For example, PCI or CPCI buses need to occupy many control lines and use dedicated communication chips, which are costly and have poor electromagnetic compatibility. At present, most of the backplane solutions in domestic industrial control systems lack hardware and bus communication protocol redundant control mechanisms. Because the backplane bus often uses a single controller card, a single power supply, and a single backplane bus technical solution, when any of the above parts fails, the entire communication backplane control system will shut down, the reliability is not high, and the communication data exchange speed is also very low. With the continuous improvement of the speed, reliability and security requirements of IO applications in industrial control systems, the backplane bus communication speed, reliability and security are all issues that modern high-speed backplane technical solutions must face and consider. Summary of the invention

[0003] The purpose of the present invention is to provide a high-speed communication protocol backplane with redundant controllers to address the deficiencies in the application of the above-mentioned industrial control backplane bus communication system, which ensures the communication reliability, security and high-speed data exchange of the system through hardware redundancy mechanism and bus communication protocol.

[0004] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: a high-speed communication backplane with redundant controllers, including a backplane connector and at least one main controller card and at least one IO card inserted in the backplane connector;

[0005] The main controller card is used to exchange data with the IO board card, complete the IO board card identity verification and IO signal input and output control; monitor the status of the main controller card activated on the backplane communication and the online IO board card, and immediately activate the hot standby main controller card when the main controller card in the hot standby state detects that the heartbeat signal of the activated main controller card stops or the LVDS communication times out;

[0006] The IO board is used to receive the request data message of the main controller card and send the response data message to the main controller card in the activated state to complete the identity verification and IO signal input and output control.

[0007] The main controller card is provided with a backplane redundant controller, including a backplane power supply function block, a backplane status function block and a controller status function block;

[0008] The backplane power supply function block is used to generate a low-level signal when a short circuit occurs on the IO board, and control the relay to cut off the backplane power supply of the IO board, thereby isolating the failed IO board.

[0009] The backplane status function block is used to detect the status of all level signals given on the IO board;

[0010] The controller status function block is used to control the redundant power supply output of the hot standby main controller card and monitor the heartbeat pulse signal and LVDS communication status of the activated main controller card; when it is detected that the heartbeat signal of the activated main controller card stops or the LVDS communication times out, the backplane redundant controller in the hot standby main controller card immediately activates the hot standby main controller card.

[0011] Multiple main controller cards perform data hot standby through an LVDS communication interface to achieve controller card redundancy.

[0012] The main controller card and the IO board card each have two redundant MLVDS communication interfaces for data exchange between the main controller card and the IO board card.

[0013] The backplane redundancy controller in the main controller is used to monitor the status of the main controller card and IO board card online in the backplane communication, including the working status of the main controller card, IO board card plug-in monitoring, IO board card address, IO board card type, IO board card power status, and IO board card interrupt authority allocation and scheduling.

[0014] When the two main controllers in the communication backplane are working normally, one is in hot standby redundant state and the other is in active state; when the active main controller card loses power, the heartbeat signal stops or the LVDS communication times out, the backplane redundant controller will activate the controller in hot standby redundant state and immediately take over the communication backplane bus control authority after activation.

[0015] There is an independent power control function block on the IO board slot in the communication backplane. When the IO board has a communication anomaly or the power fails, the backplane redundancy controller cuts off the power supply of the IO board through the power control function block on the backplane to achieve physical isolation.

[0016] The IO board in the communication backplane has an independent hardware address and type, so as to obtain the address and type of the IO board in real time for device identity verification and plug-in status hardware monitoring.

[0017] A high-speed communication backplane communication method with a redundant controller comprises the following steps:

[0018] After the communication backplane is powered on, in the first communication cycle, the active main controller card sends a request data message to each online IO board, and each IO board sends a response data message. The first cycle completes identity verification and timestamp configuration;

[0019] The next communication cycle enters the multiplexed time slot message cycle, and each IO board sends messages in sequence according to the scheduling sequence configured in the main controller card; when the communication backplane enters the multiplexed time slot message cycle, the backplane redundant controller in the activated main controller card detects the hot plug action of the IO board. After the multiplexed time slot message cycle ends, the communication backplane enters asynchronous interrupt communication, the main controller card sends asynchronous request data, the IO board sends asynchronous response data, performs identity verification and timestamp configuration on the inserted IO board, and removes the removed IO board from the multiplexed time slot message cycle sequence.

[0020] The response data message or request data message format includes: destination address, source address, type, timestamp, status bit, data length, data, CRC check; it is used for identity verification, time synchronization, status monitoring, and data verification.

[0021] The present invention has the following beneficial effects and advantages:

[0022] 1. The backplane bus structure is simple. The designed backplane bus uses two MLVDS differential serial buses. The high-speed connector pins of each IO board are exactly the same. IO boards can be mixed. The main controller hardware and backplane bus communication protocol both support hot-swap of IO modules, which improves the convenience of use.

[0023] 2. High reliability of backplane bus communication. The designed backplane bus uses two main controllers. A high-speed LVDS communication interface is used between the two main controller cards for data hot standby to achieve controller card redundancy. The main controller card and IO board card are interconnected through two high-speed MLVDS communication interfaces to achieve backplane bus communication redundancy. The redundant power supply function blocks in the two main controllers supply power to the backplane at the same time to achieve backplane power redundancy.

[0024] 3. Failed board isolation. There is an independent power control function block on the IO board slot in the communication backplane. When the IO board has a communication anomaly or the power fails, the backplane redundancy controller cuts off the power supply of the IO board through the power control function block on the backplane to achieve physical isolation.

[0025] 4. High security of backplane bus communication. The backplane redundant controller in the main controller monitors the IO board address and IO board type in real time, and completes identity verification together with the information in the backplane bus communication protocol message to ensure data security and reliability.

[0026] 5. The backplane bus communication data exchange efficiency is high. When the main controller card and the IO board communicate bus data, the "request response" method is used for non-periodic communication, and the "multiplexed time slot" and "asynchronous communication" combination method is used for periodic communication. During periodic communication, the bus communication protocol supports the optimized sequence combination working mode. The high-speed device and the slow device are reasonably configured by the scheduling time of each IO board, which reduces the communication idle time and improves the bus data exchange speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of the application, and do not constitute a limitation of the embodiments of the present invention;

[0028] Figure 1 This is a schematic diagram of the connection of the backplane bus hardware with redundant controllers;

[0029] Figure 2 It is a schematic diagram of the structure of the backplane redundant controller;

[0030] Figure 3 It is the main controller "request data" message and the IO module "response data" message;

[0031] Figure 4 It is the "request response" data exchange between the main controller and the IO module during non-periodic communication;

[0032] Figure 5 It is the "multiplexed time slot" and "asynchronous communication" data exchange between the main controller and the IO module during periodic communication; DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0034] The backplane communication has main controller card 1, main controller card 2, multiple IO boards, and a communication backplane with multiple high-speed connectors. A high-speed LVDS communication interface is used between the two main controller cards for data hot backup to achieve controller card redundancy. The main controller card and the IO board are interconnected through two high-speed MLVDS communication interfaces to achieve backplane communication bus redundancy.

[0035] The main controller card is equipped with a backplane redundancy controller, which is responsible for monitoring the status of the main controller card and IO board cards online in the backplane communication. It mainly includes the working status of the main controller card, IO board card plug-in monitoring, IO board card address, IO board card type, IO board card power status, and IO board card interrupt permission allocation and scheduling. When an IO board card has a communication anomaly or a power failure, the backplane redundancy controller cuts off the power supply of the IO board card through the power control function block on the communication backplane, and improves the stability and reliability of the communication backplane through physical isolation.

[0036] When the main controller card and the IO board communicate bus data, the "request response" method is used for non-periodic communication, and the "multiplexed time slot" and "asynchronous communication" combination method is used for periodic communication. The bus communication protocol supports the optimized sequence combination working mode during periodic communication. The high-speed device and the slow device can achieve the system optimization through reasonable configuration and improve the bus data exchange speed. The bus communication protocol message includes the destination address, source address, type, timestamp, status bit, data length, data, CRC check and other contents. The message content can be used for identity verification, time synchronization, status monitoring, data verification, to ensure data security and reliability.

[0037] like Figure 1 As shown, a high-speed communication backplane with redundant controllers of the present invention mainly includes: two high-speed backplane connectors for main controller card slots, multiple high-speed backplane connectors for IO card slots, two MLVDS interface communication buses, one LVDS interface communication bus for communication between main controllers, and a backplane redundant controller. The communication speed of the two MLVDS interfaces is not less than 200Mbps, and the communication speed of the LVDS interface is not less than 100Mbps.

[0038] The two MLVDS interface communication buses in the backplane are interconnected with the two MLVDS interfaces on the main controller card and the IO board. During normal operation, the same data will be transmitted simultaneously on the two communication buses. The main controller and the IO board will judge the data from the two buses and will only receive the data when the data content is completely consistent. When the data is inconsistent, the main controller will count and accumulate, and report fault information when the accumulation reaches a certain level.

[0039] The active master controller sends the data and configuration information obtained from the high-speed communication backplane to the hot standby redundant controller in real time through an LVDS interface communication bus. When the hot standby redundant controller is activated, the data can be used to quickly restore the high-speed backplane to normal working state.

[0040] like Figure 2 As shown, the backplane redundant controller in the main controller is mainly composed of three functional blocks: backplane power supply, backplane status and controller status.

[0041] Backplane power supply: External DC power supply, through the redundant power supply function block in the main controller card, provides multiple independent secondary DC power supplies to the bus backplane. The backplane power supply function block is responsible for distributing the secondary DC power supply to the high-speed connector power pins of each IO board slot on the high-speed backplane, and monitors the level status given by the power monitoring chip on the IO board. When a short circuit occurs in the IO module, when the power monitoring chip gives a low level, the backplane power supply function block controls the relay to cut off the backplane power supply of the IO module and isolate the failed IO board.

[0042] Backplane status: Each IO board has an IO board status function block, including the IO board slot address, IO type, reset signal, synchronization signal, interrupt signal, etc. The backplane status function block is responsible for sending the high and low level signal combination status in the IO board status function block to the backplane redundancy controller.

[0043] Controller status: responsible for enabling the output of the redundant power supply of the main controller, monitoring the controller heartbeat pulse level, and communication status. When the heartbeat stops or the communication disappears, the controller status function block sends a low-level signal to the backplane redundant controller, and the backplane redundant controller activates the hot standby main controller.

[0044] like Figure 3 As shown in the figure, they are the "response data" message of the IO board and the "request data" message of the main controller card. The bus communication protocol message includes the destination address, source address, type, timestamp, status bit, data length, data, CRC check, etc. The message content can be used for identity verification, time synchronization, status monitoring, data verification, and ensure data security and reliability.

[0045] like Figure 4 , Figure 5 As shown, after the communication backplane is powered on, the main controller in the first communication cycle that is in the active state will send a "request data" message to each online IO board, and each IO board will send a "response data" message. The first cycle needs to complete identity verification and timestamp configuration. The next communication cycle enters the "multiplexed time slot" message cycle, and each IO board sends messages in sequence according to the main controller scheduling sequence. When the communication backplane enters the "multiplexed time slot" message cycle, when the backplane redundant controller detects the hot plug action of the IO board, the communication backplane will enter asynchronous interrupt communication after the "multiplexed time slot" message cycle ends, the main controller sends "asynchronous request" data, and the IO module sends "asynchronous response" data. The identity verification and timestamp configuration of the inserted IO board are performed, and the IO board is removed and removed from the "multiplexed time slot" message cycle sequence.

Claims

1. A high-speed communication backplane communication method with redundant controllers, characterized in that: The following steps are involved: After the communication backplane is powered on, in the first communication cycle, the active main controller card sends a request data message to each online IO board, and each IO board sends a response data message. The first cycle completes identity verification and timestamp configuration; The next communication cycle enters the multiplexed time slot message cycle, and each IO board sends messages in sequence according to the scheduling sequence configured in the main controller card; When the communication backplane enters the multiplexed time slot message cycle, the backplane redundant controller in the activated main controller card detects the hot plug action of the IO board. After the multiplexed time slot message cycle ends, the communication backplane enters asynchronous interrupt communication, the main controller card sends asynchronous request data, the IO board sends asynchronous response data, performs identity verification and timestamp configuration on the inserted IO board, and removes the removed IO board from the multiplexed time slot message cycle sequence.

2. A high-speed communication backplane communication method with redundant controller according to claim 1, characterized in that: The response data message or request data message format includes: destination address, source address, type, timestamp, status bit, data length, data, CRC check; it is used for identity verification, time synchronization, status monitoring, and data verification.

3. A high-speed communication backplane with redundant controllers, used to implement the high-speed communication backplane communication method with redundant controllers as claimed in claim 1, characterized in that: It includes a backplane connector and at least one main controller card and at least one IO card plugged into the backplane connector; The main controller card is used to exchange data with the IO board card, complete the IO board card identity verification and IO signal input and output control; monitor the status of the main controller card activated on the backplane communication and the online IO board card, and immediately activate the hot standby main controller card when the main controller card in the hot standby state detects that the heartbeat signal of the activated main controller card stops or the LVDS communication times out; The IO board is used to receive the request data message of the main controller card and send the response data message to the main controller card in the activated state to complete the identity verification and IO signal input and output control.

4. A high-speed communication backplane with redundant controller according to claim 3, characterized in that: The main controller card is provided with a backplane redundant controller, including a backplane power supply function block, a backplane status function block and a controller status function block; The backplane power supply function block is used to generate a low-level signal when a short circuit occurs on the IO board, and control the relay to cut off the backplane power supply of the IO board, thereby isolating the failed IO board. The backplane status function block is used to detect the status of all level signals given on the IO board; The controller status function block is used to control the redundant power supply output of the hot standby main controller card and monitor the heartbeat pulse signal and LVDS communication status of the activated main controller card; when it is detected that the heartbeat signal of the activated main controller card stops or the LVDS communication times out, the backplane redundant controller in the hot standby main controller card immediately activates the hot standby main controller card.

5. A high-speed communication backplane with redundant controller according to claim 3, characterized in that: Multiple main controller cards perform data hot standby through an LVDS communication interface to achieve controller card redundancy.

6. A high-speed communication backplane with redundant controller according to claim 3, characterized in that: The main controller card and the IO board card each have two redundant MLVDS communication interfaces for data exchange between the main controller card and the IO board card.

7. A high-speed communication backplane with redundant controllers according to claim 4, characterized in that: The backplane redundancy controller in the main controller card is used to monitor the status of the main controller card and IO board card online in the backplane communication, including the working status of the main controller card, IO board card plug-in monitoring, IO board card address, IO board card type, IO board card power status, and IO board card interruption authority allocation and scheduling.

8. The high-speed communication backplane with redundant controller according to claim 3, characterized in that: When the two main controllers in the communication backplane are working normally, one is in hot standby redundant state and the other is in active state; when the active main controller card loses power, the heartbeat signal stops or the LVDS communication times out, the backplane redundant controller will activate the controller in hot standby redundant state and immediately take over the communication backplane bus control authority after activation.

9. A high-speed communication backplane with redundant controllers according to claim 3, characterized in that: There is an independent power control function block on the IO board slot in the communication backplane. When the IO board has a communication anomaly or the power fails, the backplane redundancy controller cuts off the power supply of the IO board through the power control function block on the backplane to achieve physical isolation.

10. The high-speed communication backplane with redundant controller according to claim 3, characterized in that: The IO board in the communication backplane has an independent hardware address and type, so as to obtain the address and type of the IO board in real time for device identity verification and plug-in status hardware monitoring.

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