CAN communication auxiliary channel data transmission method

Abstract

The present invention provides a CAN communication auxiliary channel data transmission method, which comprises the following steps: establishing an auxiliary channel DBC file; auxiliary channel mapping; process step flow editing; starting a test; during the test; until the process step flow is executed, the test ends; the beneficial effects of the present invention are: reducing the resource occupation of the intermediate computer, and being able to carry more auxiliary channels; reducing the development cost of the docking protocol between the auxiliary channel lower computer and the intermediate computer; the CAN communication has strong real-time performance and fast transmission speed, and can improve the sampling frequency; the auxiliary channel DBC file is easy to edit, the protocol structure is simple, and the scalability is strong; only a small amount of voltage, temperature, and pressure messages need to be defined to meet the auxiliary channel type and data upload; when an auxiliary channel fails, only the auxiliary channel mapping needs to be modified, the failed auxiliary channel is deleted, and other auxiliary channels are mapped, and there is no need to replace the auxiliary channel lower computer, thereby improving the equipment utilization rate.

Description

Technical Field

[0001] The present invention relates to the technical field of battery testing, and in particular to a CAN communication auxiliary channel data transmission method. Background Art

[0002] The auxiliary channel is mainly used to collect the voltage, temperature and pressure data of the single cell to monitor the status of the single cell. The data collected by the auxiliary channel can also be used as protection conditions and the cut-off conditions of the process. Although it cannot charge and discharge the battery, it can play a great auxiliary role in the battery testing process, so the auxiliary channel is also widely used in battery testing. The data sampling and feedback of the auxiliary channel are performed by the auxiliary channel lower computer. The traditional hardware design is that each auxiliary channel lower computer is composed of multiple auxiliary channels, and each auxiliary channel is independent of each other and does not interfere with each other. When the auxiliary channel lower computer is working, the sampled data of each auxiliary channel is sent to the middle computer through the serial port, and then sent to the server by the middle computer, and then sent to the client by the server, and finally presented to the user by the client. However, the serial port communication speed is slow and the data capacity is low. The middle computer must handle the charge / discharge logic of the main channel, the data sampling of the main channel and the auxiliary channel, and the communication with the server, resulting in insufficient performance of the middle computer and unable to carry more channels. At the same time, there is no unified industry standard for the communication protocol between the auxiliary channel lower computer and the middle computer. There are differences between different models. When the auxiliary channel updates and iterates the product, it is necessary to repeatedly develop the communication protocol between the auxiliary channel lower computer and the middle computer, which greatly increases the development cost. Summary of the invention

[0003] The purpose of the present invention is to solve the shortcomings of the above-mentioned technical problems and provide a novel CAN communication auxiliary channel data transmission method. CAN communication has strong real-time performance and fast transmission speed, and can improve the sampling frequency; the auxiliary channel DBC file is easy to edit, the protocol structure is simple, and the scalability is strong; only a small number of voltage, temperature, and pressure messages need to be defined to meet the auxiliary channel type and data upload; when an auxiliary channel fails, only the auxiliary channel mapping needs to be modified, the failed auxiliary channel needs to be deleted, and other auxiliary channels need to be mapped, without replacing the auxiliary channel lower computer, thereby improving equipment utilization.

[0004] The present invention is achieved through the following technical solutions:

[0005] A CAN communication auxiliary channel data transmission method, comprising the following steps:

[0006] S1: Click the client software of the battery testing device, and then click the DBC editor on the client software to open the DBC editor, edit the auxiliary channel DBC protocol parameters, and generate the auxiliary channel DBC protocol configuration file;

[0007] S2: Perform environment deployment on the auxiliary channel lower computer of the battery testing equipment, burn or import the auxiliary channel DBC protocol configuration file, and the auxiliary channel lower computer traverses the auxiliary channel to form an auxiliary channel sampling CAN data frame, and sends the auxiliary channel sampling CAN data frame to the network link through the CAN interface of the auxiliary channel lower computer;

[0008] S3: Mapping the auxiliary channel on the client software of the battery detection device, that is, mapping the auxiliary channel according to the actual physical wiring, forming a binding relationship between the auxiliary channel and the main channel of the battery detection device, and saving the binding information to the database;

[0009] S4: The client software of the battery testing equipment is provided with a process step editor. Then open the process step editor, import the auxiliary channel DBC protocol configuration file, and edit the process step parameters. The process step includes DBC protocol configuration parameters, custom variable modules, and several process step parameter modules. Custom variable modules can be set according to the application scenario. The custom variable module includes several custom variables. Each custom variable includes a variable name, calculation method, unit, and signal set. The signal set is a number of target signals selected from the auxiliary channel DBC protocol configuration file.

[0010] S5: After the editing of the process step in step S4 is completed, click Start, the client software of the battery detection system obtains the auxiliary channel mapping information of the start channel from the database, performs signal filtering on the DBC protocol configuration parameters and the custom variable module in the process step parameters, and packages the filtered process step parameters and sends them to the server, which sends them to the intermediate computer, and the intermediate computer starts the channel test;

[0011] S6: During the test, the intermediate computer parses the auxiliary channel sampling CAN data frame in the network link to obtain the signal sampling value in the process parameters of the channel execution step. If the process parameters contain custom variables, the signal sampling value of the signal set of the custom variable is calculated according to the calculation method to obtain the custom variable calculation value, and the auxiliary channel signal sampling value and the custom variable calculation value are sent to the server. The server forwards them to the client of the battery detection device, and the client channel interface displays the auxiliary channel signal sampling value and the custom variable calculation value in real time.

[0012] S7: The test ends when the process steps on the client software of the battery testing device are completed.

[0013] As a further step, the auxiliary channel DBC protocol configuration file includes a message set module; the message set module includes at least one message, and the message parameters include message name, message ID, frame type, comment, and signal set; the signal parameters include signal name, start bit, bit width, byte order, data type, change ratio, offset, unit, symbol, signal type, and multiplexing parameters; the signal types include ordinary signals, control signals, and multiplexed signals; the multiplexing parameters include control signals and multiplexing values, and the multiplexing parameters are valid when the signal type is a multiplexed signal, otherwise they are invalid; when editing the auxiliary channel DBC protocol configuration file, edit several messages, and use the message ID to represent the corresponding auxiliary channel type. When editing the signal set for each message, edit a control signal and at least one multiplexed signal, and the auxiliary channel types include voltage, pressure, temperature, and voltage + temperature.

[0014] As a further feature, the control signal, that is, the other signals used to control the current message, can flexibly use the same message ID to transmit different data contents, and different values ​​of the control signal represent different signals.

[0015] As a further feature, the multiplexed signal, that is, the message storage location where the current signal is located, can be multiplexed into multiple signals, and the specific data indicating which signal is determined by the control signal and the multiplexing value, and the multiplexing value corresponds to the auxiliary channel number.

[0016] As a further feature, the auxiliary channel sampling CAN data frame includes an information part and a data part, the information part includes a message ID, and the data part includes an auxiliary channel number and sampling data.

[0017] As a further example, the calculation method includes maximum value, minimum value, average value, range value, and cumulative value.

[0018] As a further step, the signal filtering is to traverse the message set in the DBC protocol configuration parameters, and then to traverse the signal set of the message, only retaining the multiplexed signal whose multiplexing value is the auxiliary channel number and the control signal corresponding to the multiplexed signal, to obtain the auxiliary channel signal set, and to traverse the signal set of the custom variables in the work step process parameters to eliminate the signals that cannot be found in the auxiliary channel signal set.

[0019] As a further feature, the battery detection device includes a client, a server, a database, a middle computer, a main channel lower computer, and an auxiliary channel lower computer. Each server is connected to several middle computers, each middle computer is connected to several main channel lower computers and auxiliary channel lower computers, each main channel lower computer has several main channels, and each auxiliary channel lower computer has several auxiliary channels.

[0020] The beneficial effects of the present invention are: reducing the resource occupation of the middle computer and being able to carry more auxiliary channels; reducing the development cost of the docking protocol between the auxiliary channel lower computer and the middle computer; CAN communication has strong real-time performance and fast transmission speed, and can increase the sampling frequency; the auxiliary channel DBC file is easy to edit, the protocol structure is simple, and the scalability is strong; only a small amount of voltage, temperature, and pressure messages need to be defined to meet the auxiliary channel type and data upload; when an auxiliary channel fails, only the auxiliary channel mapping needs to be modified, the failed auxiliary channel needs to be deleted, and other auxiliary channels can be mapped, without replacing the auxiliary channel lower computer, thereby improving equipment utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of the data transmission method of the CAN communication auxiliary channel of the present invention. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods, and the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention; in addition, the embodiments in this application and the features in the embodiments can be combined with each other without conflict.

[0023] Implementation example Figure 1 As shown, a CAN communication auxiliary channel data transmission method comprises the following steps:

[0024] S1: Click the client software of the battery testing device, and then click the DBC editor on the client software to open the DBC editor, edit the auxiliary channel DBC protocol parameters, and generate the auxiliary channel DBC protocol configuration file;

[0025] S2: Perform environment deployment on the auxiliary channel lower computer of the battery testing equipment, burn or import the auxiliary channel DBC protocol configuration file, and the auxiliary channel lower computer traverses the auxiliary channel to form an auxiliary channel sampling CAN data frame, and sends the auxiliary channel sampling CAN data frame to the network link through the CAN interface of the auxiliary channel lower computer;

[0026] S3: Mapping the auxiliary channel on the client software of the battery detection device, that is, mapping the auxiliary channel according to the actual physical wiring, forming a binding relationship between the auxiliary channel and the main channel of the battery detection device, and saving the binding information to the database;

[0027] S4: The client software of the battery testing equipment is provided with a process step editor. Then open the process step editor, import the auxiliary channel DBC protocol configuration file, and edit the process step parameters. The process step includes DBC protocol configuration parameters, custom variable modules, and several process step parameter modules. Custom variable modules can be set according to the application scenario. The custom variable module includes several custom variables. Each custom variable includes a variable name, calculation method, unit, and signal set. The signal set is a number of target signals selected from the auxiliary channel DBC protocol configuration file.

[0028] S5: After the editing of the process step in step S4 is completed, click Start, the client software of the battery detection system obtains the auxiliary channel mapping information of the start channel from the database, performs signal filtering on the DBC protocol configuration parameters and the custom variable module in the process step parameters, and packages the filtered process step parameters and sends them to the server, which sends them to the intermediate computer, and the intermediate computer starts the channel test;

[0029] S6: During the test, the intermediate computer parses the auxiliary channel sampling CAN data frame in the network link to obtain the signal sampling value in the process parameters of the channel execution step. If the process parameters contain custom variables, the signal sampling value of the signal set of the custom variable is calculated according to the calculation method to obtain the custom variable calculation value, and the auxiliary channel signal sampling value and the custom variable calculation value are sent to the server. The server forwards them to the client of the battery detection device, and the client channel interface displays the auxiliary channel signal sampling value and the custom variable calculation value in real time.

[0030] S7: The test ends when the process steps on the client software of the battery testing device are completed.

[0031] Preferably, the auxiliary channel DBC protocol configuration file includes a message set module; the message set module includes at least one message, and the message parameters include message name, message ID, frame type, comment, and signal set; the signal parameters include signal name, start bit, bit width, byte order, data type, change ratio, offset, unit, symbol, signal type, and multiplexing parameters; the signal types include ordinary signals, control signals, and multiplexed signals; the multiplexing parameters include control signals and multiplexing values, and the multiplexing parameters are valid when the signal type is a multiplexed signal, otherwise they are invalid; when editing the auxiliary channel DBC protocol configuration file, edit several messages, and use the message ID to represent the corresponding auxiliary channel type. When editing the signal set for each message, edit a control signal and at least one multiplexed signal, and the auxiliary channel types include voltage, pressure, temperature, and voltage + temperature.

[0032] Preferably, the control signal, that is, other signals used to control the current message, can flexibly use the same message ID to transmit different data contents, and different values ​​of the control signal represent different signals.

[0033] Preferably, the multiplexed signal, that is, the message storage location where the current signal is located, can be multiplexed into multiple signals, and the specific data indicating which signal is determined by the control signal and the multiplexing value, and the multiplexing value corresponds to the auxiliary channel number.

[0034] Preferably, the auxiliary channel sampling CAN data frame includes an information part and a data part, the information part includes a message ID, and the data part includes an auxiliary channel number and sampling data.

[0035] Preferably, the calculation method includes maximum value, minimum value, average value, range value and cumulative value.

[0036] Preferably, the signal filtering is to traverse the message set in the DBC protocol configuration parameters, and then to traverse the signal set of the message, and only retain the multiplexed signal whose multiplexing value is the auxiliary channel number and the control signal corresponding to the multiplexed signal to obtain the auxiliary channel signal set, and to traverse the signal set of the custom variables in the work step process parameters to eliminate the signals that cannot be found in the auxiliary channel signal set.

[0037] Preferably, the battery detection device includes a client, a server, a database, a middle computer, a main channel lower computer, and an auxiliary channel lower computer. Each server is connected to several middle computers, each middle computer is connected to several main channel lower computers and auxiliary channel lower computers, each main channel lower computer has several main channels, and each auxiliary channel lower computer has several auxiliary channels.

[0038] Example 1: Taking the auxiliary channel type "16 voltage + 16 temperature" as an example, it means that there are 32 auxiliary channels, of which 1-16 are auxiliary channel voltages and 17-32 are auxiliary channel temperatures. Open the DBC editing interface of the battery detection system client, edit the auxiliary channel DBC protocol configuration file, and first add two messages, message 1 and message 2. The ID of message 1 is 1, indicating voltage, and the ID of message 2 is 2, indicating temperature.

[0039] Add a control signal "VoltIndex" to message 1, and use the first byte of message 1 to store the value of the control signal. Then start adding a multiplexing signal "V1", and use the second to fifth bytes of message 1 to store the data of "V1". The data format is float, the control signal is "VoltIndex", and the multiplexing value is "1", indicating auxiliary channel 1; then add a multiplexing signal "V2", and use the second to fifth bytes of message 1 to store the data of "V2". The data format is float, the control signal is "VoltIndex", and the multiplexing value is "2", indicating auxiliary channel 2; and so on, add multiplexing signals "V3"-"V16", indicating auxiliary channels 3-16 respectively.

[0040] Then add a control signal "TempIndex" to message 2, use the first byte of message 2 to store the value of the control signal, and then start adding a multiplexing signal "T1", use the second to fifth bytes of message 2 to store the data of "T1", the data format is float, the control signal is "TempIndex", and the multiplexing value is "17", indicating auxiliary channel 17; then add a multiplexing signal "T2", use the second to fifth bytes of message 2 to store the data of "T2", the data format is float, the control signal is "TempIndex", and the multiplexing value is "18", indicating auxiliary channel 18, and so on, add multiplexing signals "T3"-"T16", indicating auxiliary channels 17-32 respectively. After the parameter editing is completed, click the Save button to save it as the auxiliary channel DBC protocol configuration file.

[0041] Taking the auxiliary channel type "16 voltages + 16 temperatures" as an example, the auxiliary channel lower computer traverses the 32 auxiliary channels to form auxiliary channel sampling CAN data frames. The sampled CAN data frame information part of auxiliary channel 1 has a message ID of 1, and the data part is the auxiliary channel number 1 and the voltage sampling value of auxiliary channel 1. The sampled CAN data frame information part of auxiliary channel 2 has a message ID of 1, and the data part is the auxiliary channel number 2 and the voltage sampling value of the auxiliary channel, and so on, until the sampled CAN data frames of 32 auxiliary channels are packaged and sent to the network link through the CAN interface of the auxiliary channel lower computer.

[0042] Taking the auxiliary channel type "16 voltages + 16 temperatures" and the middle machine 11 as an example, there are 32 auxiliary channels, of which 1-16 are auxiliary channel voltages, 17-32 are auxiliary channel temperatures, and the middle machine 11 has 4 main channels; main channel 1 is physically connected to auxiliary channels 1, 2, 17, and 18, that is, main channel 1 carries 2 auxiliary channel voltages and auxiliary channel temperatures respectively, and the auxiliary channel mapping is 1, 2, 17, and 18; main channel 2 is physically connected to auxiliary channels 3, 4, 19, and 20, that is, main channel 2 also carries 2 auxiliary channel voltages and auxiliary channel temperatures respectively, and the auxiliary channel mapping is 3, 4, 19, and 20. Click Save to save the mapping relationship to the database.

[0043] Take the auxiliary channel DBC protocol configuration file of the auxiliary channel type "16 voltage + 16 temperature" as an example. Import the auxiliary channel DBC protocol configuration file during step editing to edit the step process parameters. The step process includes DBC protocol configuration parameters, custom variable modules, and several step parameter modules. Set the custom variable module, add the custom variable "maximum value of auxiliary channel voltage", select "maximum value" for calculation method, and select "V1"-"V16" for signal.

[0044] Taking the auxiliary channel type "16 voltage + 16 temperature" and the start of channel 1 of the intermediate machine 11 as an example, the auxiliary channels are mapped to 1, 2, 17, and 18. The DBC protocol configuration parameters and the custom variable module in the process parameters are filtered. First, the message set in the DBC protocol configuration parameters is traversed, and then the signal set of the message is traversed. Among them, the signal "V1" is a multiplexed signal and the multiplexed value is "1", the signal "V2" is a multiplexed signal and the multiplexed value is "2", the signal "T1" is a multiplexed signal and the multiplexed value is "17", the signal "T2" is a multiplexed signal and the multiplexed value is "18", and the control signal of the multiplexed signals "V1" and "V2" is "Vo ltIndex", the control signal of the multiplexed signals "T1" and "T2" is "TempIndex", and the auxiliary channel signal set is obtained. The signals in the auxiliary channel signal set are "V1", "V2", "VoltIndex", "T1", "T2", and "TempIndex". Then, the signal set of the custom variable "maximum value of auxiliary channel voltage" in the process step parameters is traversed, and the signals that cannot be found in the auxiliary channel signal set are eliminated. The signal set of the custom variable "maximum value of auxiliary channel voltage" is obtained as signals "V1, V2", and the filtered process step parameters are sent to the server, and the server sends them to the intermediate computer, which starts the channel test.

[0045] During the test, the middle computer parses the auxiliary channel sampling CAN data frame in the network link. Assuming that 32 frames of auxiliary channel sampling CAN data frames are currently received from the auxiliary channel lower computer, the CAN data frames are traversed. The message ID of the first CAN data frame is 1, and the message ID of the signal "V1" in the step process parameter is 1, indicating that it needs to be parsed. Then the data part of the CAN data frame is parsed. The value of the first byte is 1, indicating that the auxiliary channel number is 1. Then the data of the 2nd to 5th bytes are parsed to obtain the sampling value of V1. And so on, the signals "V2" and "T1" are obtained. , and the sampling value of "T2". Assuming that the sampling value of signal "V1" is "3.11V", the sampling value of signal "V2" is "3.12V", the signal set of the custom variable "maximum voltage of auxiliary channel" is signals "V1" and "V2", and the calculated maximum value is "3.12V". The sampling values ​​of auxiliary channel signals and the calculated values ​​of custom variables are sent to the server, and the server forwards them to the client of the battery detection device. The channel interface of the client displays the sampling values ​​of auxiliary channel signals "V1", "V2", "T1", and "T2" and the calculated value of the custom variable "maximum voltage of auxiliary channel" in real time.

[0046] According to the disclosure and teaching of the above description, those skilled in the art to which the present invention belongs may also make appropriate changes and modifications to the above embodiments. Therefore, the present invention is not limited to the specific embodiments disclosed and described above, and some modifications and changes to the present invention should also fall within the scope of protection of the claims of the present invention. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation to the present invention.

Claims

1. A CAN communication auxiliary channel data transmission method, characterized in that: Follow these steps: S1: Click the client software of the battery testing device. The client software is provided with a DBC editor. Open the DBC editor, edit the auxiliary channel DBC protocol configuration parameters, and generate an auxiliary channel DBC protocol configuration file. The auxiliary channel DBC protocol configuration file includes a message set module; the message set module includes at least one message, the message includes a message name, a message ID, a frame type, a comment and a message signal set; the message signal set includes at least one signal, the signal includes a signal name, a start bit, a bit width, a byte order, a data type, a change ratio, an offset, a unit, a symbol, a signal type and a multiplexing parameter; the signal type includes a common signal type, a control signal type and a multiplexing signal type; the multiplexing parameter includes a control signal and a multiplexing value, and the multiplexing parameter is valid when the signal type is a multiplexed signal type, otherwise it is invalid; when editing the auxiliary channel DBC protocol configuration file, edit several messages under the message set module, and use the message ID to represent the corresponding auxiliary channel type. When editing the message signal set of each message, edit a control signal and at least one multiplexing signal, and the auxiliary channel types include voltage, pressure, temperature and voltage + temperature; S2: Perform environment deployment on the auxiliary channel lower computer of the battery testing equipment, burn or import the auxiliary channel DBC protocol configuration file, and the auxiliary channel lower computer traverses the auxiliary channel to form an auxiliary channel sampling CAN data frame, and sends the auxiliary channel sampling CAN data frame to the network link through the CAN interface of the auxiliary channel lower computer; S3: Mapping the auxiliary channel on the client software of the battery detection device, that is, mapping the auxiliary channel according to the actual physical wiring, forming a binding relationship between the auxiliary channel and the main channel of the battery detection device, and saving the auxiliary channel mapping information to the database; S4: A process step editor is provided on the client software of the battery detection equipment. Then, the process step editor is opened, and the auxiliary channel DBC protocol configuration file is imported to edit the process step parameters. The process step parameters include auxiliary channel DBC protocol configuration parameters, custom variable modules, and several process step parameter modules. Custom variable modules are set according to application scenarios. Custom variable modules include several custom variables. Each custom variable includes a variable name, calculation method, unit, and custom variable signal set. The custom variable signal set is a number of target signals selected from all message signal sets under the message set module of the auxiliary channel DBC protocol configuration file. S5: After the editing of the process parameters in step S4 is completed, click Start, and the client software of the battery detection system obtains the auxiliary channel mapping information of the start channel from the database, performs signal filtering on the auxiliary channel DBC protocol configuration parameters and the custom variable module in the process parameters, and packages the filtered process parameters and sends them to the server, which sends them to the intermediate computer, and the intermediate computer starts the channel test; S6: During the test, the intermediate computer parses the auxiliary channel sampling CAN data frame in the network link to obtain the signal sampling value in the process parameter of the channel execution step. If the process parameter of the channel contains a custom variable, the signal sampling value of the custom variable signal set is calculated according to the calculation method to obtain the custom variable calculation value, and the auxiliary channel signal sampling value and the custom variable calculation value are sent to the server, and the server forwards them to the client software of the battery detection device. The channel interface of the client software displays the auxiliary channel signal sampling value and the custom variable calculation value in real time; the calculation method includes maximum value, minimum value, average value, range value and cumulative value; S7: The test ends when the process steps on the client software of the battery testing device are completed.

2. The CAN communication auxiliary channel data transmission method according to claim 1, characterized in that: The control signal is used to control other signals under the current message. Different data contents are transmitted using the same message ID. Different values ​​of the control signal represent different signals.

3. The CAN communication auxiliary channel data transmission method according to claim 1, characterized in that: The multiplexed signal indicates that the message storage location where the current signal is located can be multiplexed into multiple signals. The specific data indicating which signal is determined by the control signal and the multiplexing value. The multiplexing value corresponds to the auxiliary channel number.

4. The CAN communication auxiliary channel data transmission method according to claim 1, characterized in that: The auxiliary channel sampling CAN data frame includes an information part and a data part, the information part includes a message ID, and the data part includes an auxiliary channel number and sampling data.

5. The CAN communication auxiliary channel data transmission method according to claim 1 is characterized in that: The signal filtering means traversing the message set module in the DBC protocol configuration file, then traversing the message, and then traversing the message signal set of the message, only retaining the multiplexing signal whose multiplexing value is the auxiliary channel number and the control signal corresponding to the multiplexing signal, obtaining the auxiliary channel signal set, and traversing the custom variable signal set in the work step process parameters to eliminate the signals that cannot be found in the auxiliary channel signal set.

6. The CAN communication auxiliary channel data transmission method according to claim 1, characterized in that: The battery detection device includes client software, a server, a database, a middle computer, a main channel lower computer and an auxiliary channel lower computer. Each server is connected to several middle computers, each middle computer is connected to several main channel lower computers and auxiliary channel lower computers, each main channel lower computer has several main channels, and each auxiliary channel lower computer has several auxiliary channels.

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