A method for automatic addressing and configuration-free replacement of remote IO modules based on mutual insurance of adjacent nodes

Abstract

The application discloses a kind of remote IO module automatic addressing and configuration-free replacement method based on adjacent node mutual insurance, belongs to the technical field of industrial automation control.The method is applied to the control system formed by one total controller and N remote IO module chain series connection.When a certain module fault is replaced, new module does not need any manual configuration: left and right adjacent module respectively calls the cross verification of Right_ID and Left_ID solidified in itself, after verification, the original ID is issued to new module, and new module automatically completes Self_ID writing and neighbor relationship reconstruction.The application cancels the physical dial switch on remote IO module, realizes the complete standardization of hardware and "plug and play" configuration-free replacement, greatly reduces hardware cost and maintenance labor cost, and shortens system downtime.The application is suitable for various remote IO control systems connected in chain topology.

Description

Technical Field

[0001] This invention belongs to the field of industrial automation control technology, specifically relating to a method for automatic addressing and configuration-free replacement of remote I / O modules based on mutual protection between adjacent nodes. Background Technology

[0002] In large-scale industrial applications, such as logistics sorting centers, long-distance conveyor lines, and large production workshops, the control system typically consists of a central controller (such as a PLC) and dozens of remote I / O modules connected in a daisy-chain topology via fieldbus or industrial Ethernet. To achieve precise industrial control, the central controller must be able to accurately identify the physical location and arrangement of each remote I / O module in the link.

[0003] Currently, the mainstream method for assigning remote I / O module addresses in the industrial sector is the hardware DIP switch scheme. Specifically, a DIP switch is soldered onto the hardware circuitry of each remote I / O module. During installation, field engineers manually adjust the switches to create different hardware ID values ​​based on the module's order and position in the chain topology. The central controller distinguishes modules by reading these hardware IDs. When a module in the chain fails, maintenance personnel need to take a new module, manually adjust its DIP switches to the exact same state as the old module, and then replace it.

[0004] The aforementioned existing technical solutions have the following main drawbacks: (1) High hardware costs. Each remote I / O module must be configured with an additional physical DIP switch and its peripheral circuitry. In large systems with a large number of I / O modules, this cost accumulates to a considerable amount, significantly increasing the overall hardware manufacturing cost.

[0005] (2) High labor costs and long maintenance time. Both the installation and replacement phases require manual physical DIP switch operations. In systems with dozens or even hundreds of modules, the workload of manual DIP switches is enormous, and human errors such as incorrect switches or misreading are very easy to occur, leading to difficulties in debugging and the inability of the system to communicate normally.

[0006] (3) Difficult maintenance under harsh working conditions. In harsh industrial environments (such as high temperature, dust, and confined space) or when the equipment is installed in a location that is inconvenient to access, manual maintenance is extremely time-consuming and labor-intensive, which seriously affects the maintainability of the equipment and the downtime of the system.

[0007] (4) Low degree of module standardization. Because different modules in different locations need to be set with different DIP switch values, each module cannot be completely standardized at the factory, which increases the complexity of inventory management and spare parts management.

[0008] To address the aforementioned issues, some existing technologies have attempted to achieve automatic address allocation through software. For example, Chinese Patent Publication No. CN120315365A discloses a "PLC system control method, device, and storage medium based on dynamic address allocation." This method generates a unique logical address for each physical ID and reassigns a dynamic address after a new IO module comes online. However, this method requires global address reassignment after a module is replaced due to damage, failing to achieve "plug-and-play" configuration-free replacement, and necessitates manual intervention when the topology changes. Furthermore, US Patent US20060268854A1 discloses an automatic addressing system and method for a modular distributed IO system, allowing the omission of one or more modules without reconfiguration or reprogramming the controller. However, its addressing process relies on the global management of the master controller and lacks an autonomous collaboration mechanism between modules.

[0009] Therefore, developing an automatic addressing and configuration-free replacement method for remote I / O modules based on mutual protection between adjacent nodes is of great significance for reducing hardware costs, shortening system downtime for maintenance, and achieving true manual maintenance-free operation. Summary of the Invention

[0010] The purpose of this invention is to provide a method for automatic addressing and configuration-free replacement of remote I / O modules based on mutual protection between adjacent nodes, so as to solve the problems mentioned in the background art.

[0011] To achieve the above objectives, the present invention provides the following technical solution: an automatic addressing and configuration-free replacement method for remote I / O modules based on mutual protection between adjacent nodes, applied to a chain-like topology control system consisting of a main controller and N remote I / O modules connected in series via a communication bus, comprising the following steps: Step 1: Initialize automatic addressing upon first power-on of the system. The main controller sends an addressing instruction containing the current address count value along the communication link. Each remote IO module receives the addressing instruction in sequence, sets its own Self_ID to the current address count value, increments the address count value by 1, and forwards it to the next module until all modules have completed sequential addressing. After addressing is completed, each module exchanges data with its left neighbor module and right neighbor module respectively, and stores the ID of the left neighbor module in the Left_ID storage area and the ID of the right neighbor module in the Right_ID storage area. Step 2: Configuration-free hot-swappable replacement of faulty modules When module X in the chain topology fails and is replaced by a new module, the left neighbor module retrieves its own fixed Right_ID (with a value of X), and the right neighbor module retrieves its own fixed Left_ID (with a value of X). They then send verification queries to the new module for cross-validation. After successful verification, either the left or right neighbor module sends the ID value X to the new module. Upon receiving the ID value X, the new module writes it into its own Self_ID storage area and re-discovers neighbors with the left and right neighbor modules to restore the Left_ID and Right_ID mapping.

[0012] Preferably, the remote I / O module includes a microprocessor, non-volatile memory, an uplink communication interface, and a downlink communication interface; the non-volatile memory has a Self_ID storage area, a Left_ID storage area, and a Right_ID storage area.

[0013] Preferably, in step one, the Left_ID storage area of ​​the first module of the chain topology is defined as empty, and the Right_ID storage area of ​​the tail module is defined as empty.

[0014] Preferably, in step two, the cross-validation passes when the Right_ID retrieved by the left neighbor module is the same as the Left_ID retrieved by the right neighbor module.

[0015] Preferably, in step two, the Self_ID, Left_ID, and Right_ID storage areas of the new module are empty or have preset default values ​​at the factory.

[0016] Preferably, when the first module in the chain topology fails, the right neighboring module retrieves its own fixed Left_ID and sends it to the newly replaced first module; when the tail module in the chain topology fails, the left neighboring module retrieves its own fixed Right_ID and sends it to the newly replaced tail module.

[0017] Preferably, when two or more consecutive modules in the chain topology fail simultaneously, the system reports a multi-point continuous fault error to the main controller, triggering a global readdressing process.

[0018] Preferably, the communication bus adopts a fieldbus or an industrial Ethernet, wherein the fieldbus includes an RS-485 bus or a CAN bus, and the industrial Ethernet includes Profinet, EtherCAT, or Modbus TCP.

[0019] Preferably, a remote I / O module automatic addressing and configuration-free replacement system based on mutual protection between adjacent nodes includes: The main controller is used to send addressing instructions and receive system status information; N remote I / O modules are connected in series via a communication bus to form a chain topology. Each remote I / O module includes a microprocessor, non-volatile memory, an uplink communication interface, and a downlink communication interface. The non-volatile memory stores Self_ID, Left_ID, and Right_ID. The system performs the method as described in any one of claims 1-8.

[0020] Preferably, a remote I / O module is applied to the system as described in claim 9. The remote I / O module includes a microprocessor, a non-volatile memory, an uplink communication interface, and a downlink communication interface. The non-volatile memory has a Self_ID storage area, a Left_ID storage area, and a Right_ID storage area. When the remote I / O module is manufactured, the Self_ID, Left_ID, and Right_ID storage areas are empty or have preset default values.

[0021] Compared with the prior art, the beneficial effects of the present invention are: 1. Significantly reduces hardware costs. This invention eliminates the physical DIP switches and their peripheral adapter circuits on all remote I / O modules, achieving complete hardware standardization (single SKU), which is beneficial for large-scale mass production and inventory management.

[0022] 2. Achieve true maintenance-free operation. When on-site maintenance personnel replace modules, they do not need to consult drawings, know the location number, or manually dial switches, truly achieving "plug and play". This eliminates the risk of secondary failures caused by manual dial switch errors and significantly shortens system downtime for maintenance.

[0023] 3. High efficiency and reliability of automatic addressing. The system automatically completes the address allocation and neighbor binding of all modules when it is first powered on, without the need for manual configuration of each module. The addressing process is fast, accurate and conflict-free.

[0024] 4. Fault recovery does not require global reconfiguration. When a single module fails, local self-healing is achieved through the mutual protection mechanism of adjacent nodes, without the need for the central controller to participate in global readdressing. This results in fast recovery speed and minimal impact on system operation.

[0025] 5. Effective backup for multiple consecutive failures. In extreme cases of multiple consecutive failures, the system can automatically identify them and report them to the central controller, triggering a global readdressing process to ensure that the system is recoverable under any circumstances.

[0026] 6. Wide range of applications. This invention is applicable to various remote I / O control systems that use a chain-like topology connection, including industrial automation control systems based on multiple communication protocols such as RS-485, CAN bus, Profinet, EtherCAT, and Modbus TCP. Attached Figure Description

[0027] Figure 1 This is the overall program flowchart of the present invention; Figure 2 : This is a flowchart of the ID addressing procedure of the present invention; Figure 3 : Flowchart of the automatic ID identification program for the replacement module of this invention; Figure 4 : This is a flowchart illustrating the field application scenario of the present invention; Figure 5 This is a flowchart illustrating the scenario of replacing a module when there is an abnormality in the field of the present invention. Detailed Implementation

[0028] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1: System Architecture and Module Hardware Configuration This embodiment provides a remote I / O control system based on the method of the present invention, which is applied to the conveyor line control system of a large logistics sorting center.

[0030] System Configuration: When each remote I / O module leaves the factory, the Self_ID, Left_ID, and Right_ID storage areas in its EEPROM are all empty (0xFFFF).

[0031] Example 2: Automatic Addressing Process for First Power-On of the System This embodiment describes in detail the automatic addressing process after the system is first installed and powered on.

[0032] Execution steps: Step 1: The main controller issues an addressing instruction. After the main controller powers on, it sends an "auto-addressing" instruction to the first remote I / O module (physical location 1) along the Profinet communication link. The instruction contains the current address count value, which is initially set to 1.

[0033] Step 2-32: Sequentially incrementing addressing. Each module performs the following operations in sequence: When the first module receives the addressing instruction (address count = 1), it writes its own Self_ID to the EEPROM with a value of 1; it then increments the address count by 1 (becoming 2) and forwards it to the second module.

[0034] The second module receives the addressing instruction (address count = 2), writes its own Self_ID to the EEPROM with a value of 2, increments the address count by 1 (becoming 3), and then forwards it to the third module.

[0035] ... The 32nd module receives the addressing instruction (address count = 32), writes its own Self_ID to the EEPROM with a value of 32; since it detects that it is the last module in the chain topology (no downlink interface connection), it no longer forwards the addressing instruction.

[0036] Step 3: Neighbor Discovery and ID Binding. After addressing is completed, each module performs neighbor discovery in sequence: The first module (first module): sends a neighbor discovery request to the left neighbor (controller side), receives no response, and sets Left_ID to Null (0x0000); sends a request to the right neighbor module (second module), confirming Right_ID=2.

[0037] The second module confirms Left_ID=1 with the left neighbor module (the first module) and Right_ID=3 with the right neighbor module (the third module).

[0038] ... Module 16: Confirm Left_ID=15 with the left neighbor module (Module 15); confirm Right_ID=17 with the right neighbor module (Module 17).

[0039] ... Module 32 (Tail Module): Confirms Left_ID=31 with the left neighbor module (Module 31); sends a request to the right neighbor direction, receives no response, and sets Right_ID to Null (0x0000).

[0040] Example 3: Configuration-free replacement process for single module failure This embodiment takes the failure of the 16th module in a chain topology as an example to describe in detail the self-healing process of configuration-free replacement.

[0041] Initial state: The system is running normally, and the storage states of each module are as follows: Fault occurred: Module 16 stopped working due to a hardware failure, and communication was interrupted.

[0042] Maintenance procedure: On-site maintenance personnel take a new module with the factory default settings (Self_ID, Left_ID, and Right_ID are all empty values), physically replace the position of the 16th module, and then power it on again.

[0043] Self-healing process: (1) New node access detection. After the new module is powered on, the downlink Profinet interface of its left neighbor module (the 15th module) detects the new device access; the uplink Profinet interface of its right neighbor module (the 17th module) also detects the new device access.

[0044] (2) Topology cross-verification. The left neighbor module (the 15th module) retrieves the Right_ID (value 16) stored in its own EEPROM and sends a verification query to the new module through the communication link: "Is the ID you should set to 16?" The right neighbor module (the 17th module) retrieves the Left_ID (value 16) stored in its own EEPROM and sends a verification query to the new module: "Is the ID you should set to 16?" After receiving the two queries, the new module compares the contents of the two queries. Both are 16, so the verification is consistent.

[0045] (3) Automatic ID distribution. After successful verification, the left neighbor module (the 15th module) sends the ID value 16 to the new module through the communication interface. At the same time, the right neighbor module (the 17th module) also sends the ID value 16 for double confirmation.

[0046] (4) Self-healing activation. After receiving the ID value 16, the new module writes it into the EEPROM as Self_ID=16. Subsequently, the new module initiates neighbor discovery: it requests the ID from the left neighbor module (confirming Left_ID=15) and the ID from the right neighbor module (confirming Right_ID=17). The system topology is completely repaired, and the 16th module resumes normal communication at its original address.

[0047] The entire replacement process takes about 5-10 seconds and requires no manual configuration.

[0048] Example 4: First Module Fault Handling Flow This embodiment uses the failure of the first module (first module) in a chain topology as an example to illustrate the special processing logic of the first and last modules.

[0049] Initial state: The first module (first module) has Self_ID=1, Right_ID=2, and Left_ID=Null. The second module has Self_ID=2, Left_ID=1, and Right_ID=3.

[0050] Fault and Replacement: The first module was damaged, and the maintenance personnel replaced it with a new module.

[0051] Self-healing process: 1. The right neighbor module (the second module) detected a new node accessing its uplink interface.

[0052] 2. The second module retrieves its own fixed Left_ID (value 1). Since the left side is the first module, a two-sided verification cannot be formed. The system determines that this is a first module failure scenario and directly sends the ID value 1 from the second module to the new module.

[0053] 3. The new module receives the ID value 1 and writes Self_ID=1.

[0054] 4. New module initiates neighbor discovery: confirm Left_ID=Null to the left neighbor (controller side); confirm Right_ID=2 to the right neighbor module (the second module).

[0055] 5. Topology recovery.

[0056] The handling logic for tail module failure is symmetrical to that of head module, with ID value N being sent from the left adjacent module.

[0057] Example 5: Multi-point continuous fault handling process This embodiment uses the simultaneous failure of the 16th and 17th modules in a chain topology as an example to illustrate the fallback mechanism for handling multiple consecutive failures.

[0058] Fault status: Modules 16 and 17 are simultaneously damaged, resulting in communication interruption. At this time: The 15th module has Right_ID=16 (pointing to the corrupted 16th module). The 18th module has Left_ID=17 (pointing to the corrupted 17th module). Modules 16 and 17 were unresponsive. System response: Module 15 detected that its downlink interface could not establish communication with Module 16; Module 18 detected that its uplink interface could not establish communication with Module 17. Due to the gap between the faulty nodes (two consecutive nodes cannot communicate), the left and right sides cannot simultaneously establish a valid connection with the faulty area, and cross-validation cannot be formed.

[0059] Backup solution: The system reports a "multi-point continuous fault" error to the central controller, which records the fault information and prompts "trigger global readdressing". After maintenance personnel complete the physical replacement of the two modules, the central controller re-initiates the global automatic addressing process of step one, and all 32 modules regain their sequence IDs.

[0060] Example 6: Comparative Experiment with Other Automatic Addressing Methods To verify the technical effectiveness of the method of the present invention, a comparative experiment was conducted between the method of the present invention and the existing technical solution under the same hardware conditions (32 remote IO modules, Profinet communication).

[0061] Analysis of experimental results: The method of this invention significantly outperforms traditional hardware DIP switch solutions in both initial addressing time and single-module replacement time, and completely eliminates the risk of human error. Compared with dynamic address allocation schemes, this invention does not require global address reallocation in single-module failure scenarios, resulting in shorter replacement time and less impact on system operation. In the event of multiple consecutive failures, this invention can automatically identify and trigger global readdressing, achieving a complete closed loop from local self-healing to global recovery.

[0062] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for automatic addressing and configuration-free replacement of remote I / O modules based on mutual protection between adjacent nodes, characterized in that, For a chain-like topology control system consisting of a central controller and N remote I / O modules connected in series via a communication bus, the following steps are included: Step 1: Initialize automatic addressing upon first power-on of the system. The main controller sends an addressing instruction containing the current address count value along the communication link. Each remote IO module receives the addressing instruction in sequence, sets its own Self_ID to the current address count value, increments the address count value by 1, and forwards it to the next module until all modules have completed sequential addressing. After addressing is completed, each module exchanges data with its left neighbor module and right neighbor module respectively, and stores the ID of the left neighbor module in the Left_ID storage area and the ID of the right neighbor module in the Right_ID storage area. Step 2: Configuration-free hot-swappable replacement of faulty modules When module X in the chain topology fails and is replaced by a new module, the left neighbor module retrieves its own fixed Right_ID (with a value of X), and the right neighbor module retrieves its own fixed Left_ID (with a value of X). They then send verification queries to the new module for cross-validation. After successful verification, either the left or right neighbor module sends the ID value X to the new module. Upon receiving the ID value X, the new module writes it into its own Self_ID storage area and re-discovers neighbors with the left and right neighbor modules to restore the Left_ID and Right_ID mapping.

2. The method according to claim 1, characterized in that, The remote I / O module includes a microprocessor, non-volatile memory, an uplink communication interface, and a downlink communication interface; the non-volatile memory has a Self_ID storage area, a Left_ID storage area, and a Right_ID storage area.

3. The method according to claim 1, characterized in that, In step one, the Left_ID storage area of ​​the first module of the chain topology is defined as empty, and the Right_ID storage area of ​​the tail module is defined as empty.

4. The method according to claim 1, characterized in that, In step two, the cross-validation passes when the Right_ID retrieved by the left neighbor module matches the Left_ID retrieved by the right neighbor module.

5. The method according to claim 1, characterized in that, In step two, the Self_ID, Left_ID, and Right_ID storage areas of the new module are empty or have preset default values ​​when it leaves the factory.

6. The method according to claim 1, characterized in that, When the first module in the chain topology fails, the right neighbor module retrieves its own fixed Left_ID and sends it to the newly replaced first module; when the tail module in the chain topology fails, the left neighbor module retrieves its own fixed Right_ID and sends it to the newly replaced tail module.

7. The method according to claim 1, characterized in that, When two or more consecutive modules in a chain topology fail simultaneously, the system reports a multi-point consecutive fault error to the central controller, triggering a global readdressing process.

8. The method according to claim 1, characterized in that, The communication bus adopts fieldbus or industrial Ethernet. The fieldbus includes RS-485 bus or CAN bus, and the industrial Ethernet includes Profinet, EtherCAT or Modbus TCP.

9. A remote I / O module automatic addressing and configuration-free replacement system based on mutual protection between adjacent nodes, characterized in that, include: The main controller is used to send addressing instructions and receive system status information; N remote I / O modules are connected in series via a communication bus to form a chain topology. Each remote I / O module includes a microprocessor, non-volatile memory, an uplink communication interface, and a downlink communication interface. The non-volatile memory stores Self_ID, Left_ID, and Right_ID. The system performs the method as described in any one of claims 1-8.

10. A remote I / O module, characterized in that, Applied to the system as described in claim 9, the remote I / O module includes a microprocessor, non-volatile memory, an uplink communication interface, and a downlink communication interface. The non-volatile memory has a Self_ID storage area, a Left_ID storage area, and a Right_ID storage area. When the remote I / O module is manufactured, the Self_ID, Left_ID, and Right_ID storage areas are empty or have preset default values.

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