Multi-connected air conditioner node communication method and system, electronic device and storage medium

Abstract

The application provides a multi-connected air conditioner node communication method, system, electronic equipment and storage medium. The method comprises a system initialization step and a system management step. The system initialization step comprises: the host node allocating an IP address to each slave node and storing the IP address of each slave node to a node registration table. The system management step comprises: the host node initiating a communication request to each slave node at a fixed time, and requiring each slave node to feed back respective node information for the communication request, the node information comprising IP address information allocated by the host node and attribute information of the slave node; and the host node performing a corresponding management operation according to the feedback of each slave node, the management operation comprising adding a slave node, deleting a slave node and modifying a slave node. The application can meet the application scene with a large number of nodes, and meet the needs of intelligent management of air conditioner big data.

Description

Technical Field

[0001] This invention relates to the field of multi-split air conditioning technology, and in particular to a communication method, system, electronic device and storage medium for multi-split air conditioning nodes. Background Technology

[0002] Multi-split air conditioning systems allow multiple outdoor units to control multiple indoor units in parallel. Since there are multiple indoor units, the demand for operating each unit varies. The outdoor units adjust the compressor frequency based on the demand from the indoor units to achieve the desired indoor cooling effect.

[0003] The communication mechanisms of multi-split air conditioning units on the market vary greatly. Poor communication mechanisms and control methods can affect the working efficiency of the air conditioning system and cannot meet the needs of application scenarios with a large number of nodes. For example, when the number of slave nodes in the air conditioning room reaches a certain number (e.g., 80 or more), nodes may go offline in the bus system. Furthermore, when multiple nodes send data concurrently, data delays or even data loss may occur. Summary of the Invention

[0004] This invention provides a communication method, system, electronic device, and storage medium for multi-split air conditioning nodes, in order to solve the problem that the existing technology cannot meet the needs of application scenarios with a large number of nodes.

[0005] In a first aspect, the present invention provides a communication method for multi-split air conditioning nodes, applicable to a multi-split air conditioning system with multiple air conditioning nodes, wherein each air conditioning node includes a master node and multiple slave nodes, and the method includes system initialization steps and system management steps, wherein...

[0006] The system initialization steps include:

[0007] The host node assigns an IP address to each slave node and stores the IP address of each slave node in the node registration table;

[0008] The system management steps include:

[0009] The host node periodically initiates communication requests to each slave node and requires each slave node to respond to the communication request with its own node information, which includes IP address information assigned by the host node and attribute information of the slave node.

[0010] The master node performs corresponding management operations based on the feedback from each slave node. These management operations include adding a slave node, deleting a slave node, and modifying a slave node.

[0011] In one embodiment of the present invention, before the host node assigns an IP address to each slave node, the system initialization step further includes:

[0012] When the multi-split air conditioning system is powered on for the first time, CAN configuration is performed on the master node and each slave node. The CAN configuration includes baud rate configuration, data transmission and reception configuration, and data transmission configuration.

[0013] In one embodiment of the present invention, the step of the host node assigning an IP address to each slave node includes:

[0014] The master node periodically sends a communication start frame to each slave node on the CAN bus.

[0015] Determine whether each slave node has received the communication start frame in this round of communication;

[0016] If each slave node receives the communication start frame, then each slave node sends a request frame to the master node to request its own IP address;

[0017] If a slave node fails to receive the communication start frame, the slave node that has not received the communication start frame will switch its CAN polarity every preset time period and continue to listen for whether it has received the communication start frame.

[0018] In one embodiment of the present invention, the step of the host node assigning an IP address to each slave node further includes:

[0019] Determine whether the host node has received an IP address request frame from each slave node;

[0020] If the host node receives the request frame from each slave node, it sends a response frame to each slave node to allocate the corresponding IP address;

[0021] If the host node does not receive an application frame from a slave node, the slave node will continue to send application frames to the host node every preset time interval to apply for its own IP address.

[0022] In one embodiment of the present invention, the step of storing the IP address of each slave device to the node registration table includes:

[0023] After receiving the IP address assigned to it by the master node, the slave node broadcasts its own IP address to the CAN bus via a broadcast frame.

[0024] After receiving the IP address broadcast by each slave node, the host node registers and stores the IP address of each slave node in the node registration table to complete the allocation of IP address to each slave node during the system initialization phase.

[0025] In one embodiment of the present invention, the step of the master node performing corresponding management operations based on feedback from each slave node includes:

[0026] If the host node does not receive node information from a slave node in the node registration table within a preset time period, the slave node is marked as offline to complete the operation of modifying the slave node.

[0027] If the host node receives node information from each slave node in the node registration table, it indicates that the host node and each slave node can communicate normally, and the host node continues to listen for whether the host node initiates a communication request to each slave node.

[0028] In one embodiment of the present invention, the step of the master node performing corresponding management operations based on feedback from each slave node further includes:

[0029] When a new slave node is connected to the multi-split air conditioning system, the new slave node is configured to listen to the master node on the CAN bus.

[0030] Determine whether the newly added slave node has received the communication start frame initiated by the master node to each slave node in this round of communication;

[0031] If the newly added slave node does not receive the communication start frame, it switches its own CAN polarity to continue listening to see if the communication start frame has been received.

[0032] If the newly added slave node receives the communication start frame, it sends a request frame to the host node to request its own IP address;

[0033] The host node sends a response frame to the newly added slave node to allocate the corresponding IP address;

[0034] After receiving the IP address, the newly added slave node broadcasts its own IP address to the CAN bus, and the master node stores it in the node registration table to complete the operation of adding a slave node.

[0035] In one embodiment of the present invention, the step of the master node performing corresponding management operations based on feedback from each slave node further includes:

[0036] When the host node receives a node deletion command from the central controller or cloud server, the host node sends a node deletion command to the specified slave node.

[0037] When the slave node receives the node deletion command frame sent by the master node, it clears its own IP address and replies to the master node by sending a deletion frame, indicating that its IP address is 0 and the attribute information of the slave node.

[0038] After receiving the deletion frame, the host node marks the slave node as deleted to complete the deletion operation.

[0039] In one embodiment of the present invention, the step of the master node performing corresponding management operations based on feedback from each slave node further includes:

[0040] When a slave node marked as offline or deleted by the host node needs to re-enter the multi-split air conditioning system, it needs to be powered on and reset.

[0041] Execute the process of adding a new slave node, or connect to a multi-split air conditioning system that has not undergone system initialization.

[0042] In one embodiment of the present invention, the step of performing CAN configuration on the master node and each slave node when the multi-split air conditioning system is powered on for the first time includes:

[0043] Based on the preset values ​​of prescaler, CAN clock frequency and baud rate set in the register, the value ranges of the first target phase buffer segment, the second target phase buffer segment and the target resynchronization compensation width are obtained.

[0044] The register is controlled to send data based on the value range, and the sending status information of the register is read to obtain the success rate;

[0045] The values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width are adjusted according to the success rate to obtain the optimal baud rate setting.

[0046] In one embodiment of the present invention, the step of obtaining the value ranges of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width based on the prescaler, CAN clock frequency, and baud rate preset values ​​set in the register includes:

[0047] The time quantum is obtained based on the prescaler set in the register and the CAN clock frequency;

[0048] Based on the preset values ​​of time quantum and baud rate, and according to the baud rate calculation formula, the first range of values ​​for the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width is obtained;

[0049] The formula for calculating this time quantum is:

[0050] TQ = (PRESC + 1) / f can_clk TQ represents time quantum, PRESC represents the prescaler set by the register, and f can_clk Indicates the CAN clock frequency;

[0051] The baud rate calculation formula is as follows:

[0052] BT=T SEG1 +T SEG2 =((SEG_1+2)+(SEG_2+1))×TQ, BT means

[0053] Baud rate, SEG1 represents the first target phase buffer segment, SEG2 represents the second target phase buffer segment, SEG_1 represents the first reference phase buffer segment, SEG_2 represents the second reference phase buffer segment, and T represents time.

[0054] In one embodiment of the present invention, the step of obtaining a first range of values ​​for the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width based on the preset values ​​of the time quantum and baud rate, and according to the baud rate calculation formula, includes:

[0055] The first reference phase buffer segment and the second reference phase buffer segment are set through the first reference phase buffer segment bit and the second reference phase buffer segment bit in the register, and the corresponding reference value range is:

[0056] 0≤SEG_1≤63, 0≤SEG_2≤7, 0≤SJW_1≤7, and

[0057] SEG_2+1≤SEG_1,SJW_1≤SEG_2,SJW_1 represents the reference resynchronization compensation width;

[0058] Based on the baud rate calculation formula, and according to the time quantum, the preset baud rate value, and the reference value range, the first target phase buffer segment, the second target phase buffer segment, and the first value range of the target resynchronization compensation width are obtained.

[0059] In one embodiment of the present invention, the step of controlling the register to send data based on the value range includes:

[0060] Based on the first value range, the set values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width are written into the register, which includes a transmit register and a receive register.

[0061] Set the transmit register to CAN transmit data mode and the corresponding receive register to CAN receive data mode;

[0062] Monitor the CAN bus for CAN communication data at preset time intervals;

[0063] If no CAN communication data is available, the polarity of the CAN bus is switched and listening continues; if CAN communication data is available, the received CAN communication data is written into the transmit register and the transmit register is controlled to transmit the data.

[0064] In one embodiment of the present invention, the step of reading the transmission status information of the register to obtain the success rate includes:

[0065] Read the transmission status information of the transmission register, calculate the success rate based on the number of data transmitted and the number of data successfully transmitted within the time window, and calculate the error value based on the success rate;

[0066] The formulas for calculating the success rate and error value are as follows:

[0067] Fm = Tount1 / Tcount0 * 100%;

[0068] △Fm=100%-Fm;

[0069] Where Fm represents the success rate, Tount1 represents the number of data successfully sent, Tcount0 represents the number of data sent, and △Fm represents the error value.

[0070] In one embodiment of the present invention, the step of adjusting the values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width according to the success rate to obtain the optimal baud rate setting includes:

[0071] Based on the error value and the preset baud rate value, and according to the baud rate calculation formula, the first target phase buffer segment and the second target phase buffer segment are increased, and the time quantum is decreased to perform fuzzy adjustment;

[0072] Based on the result of the fuzzy adjustment, it is determined whether the error value has decreased;

[0073] If the error value increases, the first target phase buffer segment and the second target phase buffer segment are lowered and the time quantum is increased according to the baud rate calculation formula to perform fuzzy adjustment.

[0074] Based on the fuzzy adjustment method that can reduce the error value, proportional-integral-derivative adjustment is performed while keeping the time quantum constant, so as to obtain the adjusted values ​​of the second target phase buffer segment and the target resynchronization compensation width;

[0075] Based on the adjustment value, a second range of values ​​for the second target phase buffer segment and the target resynchronization compensation width is determined.

[0076] In one embodiment of the present invention, the step of adjusting the values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width according to the success rate to obtain the optimal baud rate setting value further includes:

[0077] Based on the second value range, assign values ​​to the second target phase buffer segment and the target resynchronization compensation width;

[0078] Based on the assigned value, determine whether the error value has decreased and whether it is within the adjustment period of the optimal baud rate setting;

[0079] If the error value decreases and is within the adjustment period of the optimal baud rate setting, then when the error value is lower than or equal to the first preset threshold, the first target phase buffer segment, the second target phase buffer segment, the target resynchronization compensation width, and the time quantum are determined to be the target assignment.

[0080] The optimal baud rate setting value is obtained according to the target value and the baud rate calculation formula.

[0081] In one embodiment of the present invention, after the step of determining the optimal baud rate setting value according to the baud rate calculation formula based on the target assignment, the control method further includes:

[0082] Determine whether the adjustment period for determining the optimal baud rate setting exceeds the second preset threshold;

[0083] If it is determined that the adjustment period of the most baud rate setting exceeds the second preset threshold, then return to the step of assigning values ​​to the second target phase buffer segment and the target resynchronization compensation width based on the second value range.

[0084] Secondly, the present invention also provides a multi-split air conditioning node communication system, which has multiple air conditioning nodes, each air conditioning node including a master node and multiple slave nodes. The device includes a system initialization module and a system management module, wherein...

[0085] The system initialization module is used for:

[0086] The host node assigns an IP address to each slave node and stores the IP address of each slave node in the node registration table;

[0087] The system management module is used for:

[0088] The host node periodically initiates communication requests to each slave node and requires each slave node to respond to the communication request with its own node information, which includes the IP address information assigned by the host node and the attribute information of the slave node.

[0089] The master node performs corresponding management operations based on the feedback from each slave node. These management operations include adding a slave node, deleting a slave node, and modifying a slave node.

[0090] Thirdly, the present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the multi-split air conditioning node communication method as described in any of the first aspects.

[0091] Fourthly, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the multi-split air conditioning node communication method as described in any of the first aspects.

[0092] The present invention provides a multi-split air conditioner node communication method, system, electronic device, and storage medium. By dividing the multiple air conditioner nodes into one master node and multiple slave nodes, and by configuring the master node and slave nodes with CAN, the system is initialized and managed. In the system management step, the master node performs corresponding operations such as adding, deleting, and modifying slave nodes based on feedback from each slave node. This can meet the needs of application scenarios with a large number of nodes and the needs of intelligent management of air conditioning big data. Attached Figure Description

[0093] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0094] Figure 1 This is a flowchart illustrating the multi-split air conditioner node communication method provided by the present invention;

[0095] Figure 2 This is a schematic diagram of the process for initializing a node provided in an embodiment of the present invention;

[0096] Figure 3 This is a flowchart illustrating the modification of a node provided in an embodiment of the present invention;

[0097] Figure 4This is a flowchart illustrating the process of adding a new node according to an embodiment of the present invention;

[0098] Figure 5 This is a schematic diagram of the process for deleting a node provided in an embodiment of the present invention;

[0099] Figure 6 The CAN bit timing diagram for CAN baud rate setting provided in this embodiment of the invention;

[0100] Figure 7 This is a schematic diagram of the baud rate configuration process provided in an embodiment of the present invention;

[0101] Figure 8 This is a schematic diagram of the structure of the multi-split air conditioner node communication system provided by the present invention;

[0102] Figure 9 This is a schematic diagram of the structure of the electronic device provided by the present invention. Detailed Implementation

[0103] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0104] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein.

[0105] The technical terms involved in this invention are described below:

[0106] CAN bus is short for Controller Area Network, a serial communication bus standard that enables distributed real-time control.

[0107] To address the issue that existing technologies cannot meet the needs of applications with a large number of nodes, this invention provides a multi-split air conditioner node communication method, system, electronic device, and storage medium. By dividing the multiple air conditioner nodes into one master node and multiple slave nodes, and by configuring the master node and slave nodes with CAN, the system is initialized and managed. In the system management step, the master node performs corresponding operations such as adding, deleting, and modifying slave nodes based on feedback from each slave node. This can meet the needs of applications with a large number of nodes and the requirements of intelligent management of air conditioning big data.

[0108] The following is combined Figures 1-9 The present invention describes a multi-split air conditioner node communication method, system, electronic device, and storage medium.

[0109] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating the multi-split air conditioner node communication method provided by the present invention. A multi-split air conditioner node communication method is applied to a multi-split air conditioner system with multiple air conditioner nodes. Each air conditioner node includes a master node and multiple slave nodes, with the slave nodes including multiple outdoor slave nodes and multiple indoor slave nodes. The method includes system initialization steps and system management steps, wherein...

[0110] Step 110, the system initialization step includes:

[0111] Step 111: The host node assigns an IP address to each slave node and stores the IP address of each slave node in the node registration table.

[0112] Step 120, the system management steps include:

[0113] Step 121: The host node periodically sends communication requests to each slave node and requests each slave node to provide its own node information in response to the communication request. The node information includes the IP address information assigned by the host node and the attribute information of the slave node.

[0114] Step 122: The master node performs corresponding management operations based on the feedback from each slave node. The management operations include adding a slave node, deleting a slave node, and modifying a slave node.

[0115] The following specific embodiments will be used to describe steps 110 to 120 in detail.

[0116] Please refer to Figure 2 , Figure 2 This is a schematic diagram of the node initialization process provided in an embodiment of the present invention. Before step 111, step 110 further includes:

[0117] Step 201: Power on the multi-split air conditioning system for the first time.

[0118] Step 202: Configure the host node for CAN. The CAN configuration includes baud rate configuration, data transmission and reception configuration, and data transmission configuration.

[0119] Since both communicating parties should use the same transmission rate, i.e., both should use the same transmission baud rate, this is one of the important conditions for ensuring successful communication. Therefore, the baud rate configuration in CAN configuration is particularly important, as it can solve problems such as low data transmission rate and data congestion on the CAN bus, device disconnection, and data loss.

[0120] Step 203: The host node initiates a new round of communication.

[0121] It should be noted that the master node needs to send a communication round periodically (e.g., every 200ms) to prevent the CAN bus from being continuously occupied by erroneous devices without any idle time. The communication start frame definition sent by the master node is as follows:

[0122] Table 1: Communication Start Frame

[0123]

[0124] Step 204: The slave node initializes its own CAN configuration and listens to the master node on the CAN bus.

[0125] Step 205: Determine whether the slave node has received the communication start frame sent by the master node in this round of communication. If not received, proceed to step 206; if received, proceed to step 207.

[0126] Step 206: The slave node switches its own CAN polarity every preset time period (e.g., 5 seconds) and returns to step 204 to continue listening for whether a communication start frame has been received.

[0127] Step 207: The slave node sends a request frame to the master node on the CAN bus to request an IP address. The request frames sent are shown in the table below:

[0128] Table 2: Request Frames

[0129]

[0130] Step 208: Determine whether the host node has received the request frame for requesting an IP address sent by the slave node. If not received, proceed to step 209; if received, proceed to step 210.

[0131] Step 209: The slave node requests an IP address from the master node every preset time period (e.g., 3 seconds), that is, it returns to step 207 to continue sending a request frame for requesting an IP address to the master node on the CAN bus.

[0132] Step 210: The host node assigns an IP address to the slave node that requested the IP address and returns a response frame, as shown in the table below:

[0133] Table 3: Response Frames

[0134]

[0135]

[0136] Step 211: After receiving the IP address assigned by the master node, the slave node broadcasts its own IP address on the CAN bus via a broadcast frame, as shown in the table below:

[0137] Table 4: Broadcast Frames

[0138]

[0139] Step 212: After receiving the IP address broadcast by the slave node, the host node stores the slave node's node information in the node registration table. This node information includes IP address information and attribute information. The IP address information includes the IP address and MAC address, while the attribute information includes the slave node's software version number and project number.

[0140] Step 213: The system initialization node IP address allocation is completed.

[0141] This completes the system initialization and the assignment of IP addresses to each slave node.

[0142] Please refer to Figure 3 , Figure 3 This is a flowchart illustrating the modification of a node according to an embodiment of the present invention. In step 122 above, the step of the host node performing corresponding management operations based on feedback from each slave node includes:

[0143] Step 301: After the system initializes and assigns node IP addresses, the host node begins to manage the slave nodes.

[0144] Step 302: The master node initiates communication periodically (e.g., every 200ms), and in each round of communication, it requests each slave node to reply with its own node information.

[0145] Step 303: Determine whether the host node has received node information from the slave node in the node registration table. If no node information from the slave node is received, proceed to step 304 (node ​​deletion). If node information from the slave node is received and the node information is already registered in the node registration table, indicating that the host node and the slave node can communicate normally, return to step 302.

[0146] Step 304: If the node information of the slave node in the node registration table is not received within a preset time period (e.g., 30 seconds), the master node marks the device as offline to complete the status modification of the slave node and removes it from the communication node.

[0147] Step 305: The host node performs offline management of the slave node.

[0148] If the slave node needs to join the network, it needs to receive the communication start frame initiated by the master node again and send a broadcast frame to broadcast its own IP address and attribute information.

[0149] Please refer to Figure 4 , Figure 4 This is a flowchart illustrating the process of adding a new node according to an embodiment of the present invention. In step 122 above, the step of the master node performing corresponding management operations based on the feedback from each slave node includes:

[0150] Step 401: When a new slave node is connected to the multi-split air conditioning system, initialize the CAN configuration of the slave node and listen to the master node on the CAN bus.

[0151] Step 402: Determine whether the newly added node has obtained the communication start frame sent by the host node in this round of communication.

[0152] If not obtained, proceed to step 403;

[0153] If obtained, proceed to step 404.

[0154] Step 403: The slave node switches the CAN polarity every preset time period (e.g., 5 seconds) and returns to step 401 to continue listening to the master node on the CAN bus.

[0155] In step 404, the newly added node receives the communication start frame sent by the host node and initiates a request frame to request an IP address.

[0156] Step 405: The host node assigns an IP address to the slave node that requested the IP address.

[0157] Step 406: After receiving the IP address assigned by the master node, the slave node broadcasts its own IP address to the CAN bus.

[0158] Step 407: After receiving the IP address broadcast by the slave node, the host node stores the slave node's node information in the node registration table. This node information also includes IP address information and attribute information.

[0159] Step 408: Complete the addition of a new slave node.

[0160] Please refer to Figure 5 , Figure 5 This is a schematic diagram of the node deletion process provided in an embodiment of the present invention. In step 122 above, the step of the host node performing corresponding management operations based on feedback from each slave node includes:

[0161] Step 501: The host node receives a node deletion command from the central controller or cloud server.

[0162] Step 502: The master node initiates a new round of communication and sends a node deletion command frame to the specified slave node, as shown in the table below:

[0163] Table 5: Command Frames

[0164]

[0165] Step 503: Upon receiving the node deletion command frame from the master node, the slave node clears its own IP address and sends a deletion frame to the master node in response, replying with the master node's IP = 0 (indicating no IP address has been assigned) and the slave node's attribute information, as shown in the table below:

[0166] Table 6: Deleted Frames

[0167]

[0168]

[0169] It should be noted that the command frames in Table 5 and the deletion frames in Table 6 have the same format, but their contents are different.

[0170] Step 504: The master node marks the slave node as deleted to complete the deletion of the slave node and removes it from the communication node list.

[0171] Step 505: The master node performs deletion management on the slave node.

[0172] If the slave node is offline, it needs to be powered on and reset to rejoin the network, and the new node procedure needs to be executed again. Alternatively, it can be connected to an uninitialized CAN system network, which would require re-execution of the above procedure. Figure 2 Step 201 is shown.

[0173] As mentioned above, both the master and slave nodes in the access system need to be configured using CAN, and baud rate configuration is one aspect of CAN configuration. In practical applications, due to the inconsistent quality of CAN chips on the market, or when the number of devices on the CAN bus is very large (e.g., more than 80 nodes) and the CAN data transmission distance is very long (e.g., more than 2 km), the interference signal on the CAN bus is very large, and the arbitration competition on the CAN bus is very intense. This can cause low data transmission rate and data congestion on the CAN bus, slave device disconnection, and data loss. Therefore, it is necessary to configure the baud rate to solve the problems of low data transmission rate, data congestion, slave device disconnection, and data loss on the CAN bus.

[0174] The baud rate configuration described above is illustrated below through examples.

[0175] Please refer to Figure 6 , Figure 6 This invention provides a CAN bit timing diagram for CAN baud rate settings. The CAN protocol specifies that each bit can be divided into several non-overlapping time segments: SYNC_SEG (synchronization segment), PROP_SEG (propagation time segment), PHASE_SEG1 (first reference phase buffer segment), and PHASE_SEG2 (second reference phase buffer segment). SYNC_SEG is located at the beginning of a bit. CAN-bus specifies that the transition edge is the synchronization signal. However, there is a network propagation delay between the transmitting node sending a bit and the receiving node receiving it. PROP_SEG is used to compensate for this propagation delay. Since the sampling point is located between PHASE_SEG1 and PHASE_SEG2, the sampling point position can be adjusted by setting the values ​​of PHASE_SEG1 and PHASE_SEG2 to ensure consistent sampling for each bit. The length adjustment range of the buffer segments (PHASE_SEG1, PHASE_SEG2) is determined by the resynchronization transition width SJW.

[0176] These segments consist of the smallest unit of time called a Time Quantum (TQ). The length of each segment can be represented by an integer time quantum, which is obtained by dividing the system's clock oscillator.

[0177] Therefore, one bit is divided into four segments, and each segment consists of several TQs, which is called bit timing. The number of TQs in one bit, and the number of TQs in each segment, can be arbitrarily set in the bit timing. By setting the bit timing, multiple nodes can sample simultaneously, and the sampling points can be arbitrarily set. That is, each node can obtain different bit rates and sampling accuracies through different configurations. For example, a frequency of 100MHz divided by 4 results in 25MHz, with PRESC=4.

[0178] Due to baud rate synchronization errors, the baud rate needs to be set, which requires defining the CAN control register. This involves dividing the scalar value of one bit period into a first target phase buffer segment (SEGMENGT1) and a second target phase buffer segment (SEGMENT2). See below:

[0179] NBT=SYNC_SEG+PROP_SEG+PHASE_SEG1+PHASE_SEG2;

[0180] =SEGMENGT1+SEGMENT2.

[0181] In this context, PHASE_SEG1 will be abbreviated as SEG_1, PHASE_SEG2 as SEG_2, SEGMENGT1 as SEG1, and SEGMENT2 as SEG2.

[0182] The CAN bit timing register (CAN_BTR) is used to set parameters such as SEG1, SEG2, BRP (Baud Rate Prescaler), and SJW (reSynchronization Jump Width), which directly determine the CAN baud rate.

[0183] Please refer to Figure 7 , Figure 7 This is a schematic diagram of the baud rate configuration process provided in an embodiment of the present invention. The steps described above for configuring the baud rate for both the host node and each slave node include:

[0184] Step 710: Based on the preset values ​​of prescaler, CAN clock frequency and baud rate set in the register, obtain the value range of the first target phase buffer segment, the second target phase buffer segment and the target resynchronization compensation width.

[0185] Step 720: Control the register to send data based on the value range, and read the transmission status information of the register to obtain the success rate.

[0186] Step 730: Adjust the values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width according to the success rate to obtain the optimal baud rate setting value.

[0187] For example, in step 710 above, the step of obtaining the value range of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width based on the preset values ​​of prescaler, CAN clock frequency, and baud rate set in the MCU register includes:

[0188] Step 711: Obtain the time quantum based on the prescaler and CAN clock frequency set in the MCU register.

[0189] The formula for calculating this time quantum is:

[0190] TQ = (PRESC + 1) / f can_clk TQ represents time quantum, PRESC represents the prescaler set in the MCU register, which can be set via the PRESC bit in the BT register. can_clk Indicates the CAN clock frequency.

[0191] For example, the clock frequency used in CAN communication is can_clk (e.g., Figure 5 The clock source is an external oscillator (e.g., its frequency is 8MHz), so for example, the CAN clock frequency Fre = 50 prescaler and can_clk = 160KHz can be set.

[0192] It should be noted that TQ equals one CAN clock cycle. Generally, TQ is calculated first when determining the baud rate. The frequency is equal to the reciprocal of the cycle. CAN clock frequency = 1 / TQ = 1 / CAN clock cycle. Bit time equals the sum of the times of the above segments, and baud rate equals the reciprocal of bit time. Therefore, in the CAN bus, communication at different baud rates is achieved by controlling the bit timing register in the CAN air conditioning node.

[0193] Step 712: Based on the preset values ​​of time quantum and baud rate, and according to the baud rate calculation formula, obtain the first value range of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width.

[0194] It should be noted that the value range of step 710 above includes a first value range (see step 712) and a second value range (see step 734). The first value range is obtained based on the preset baud rate value and the chip's reference value, while the second value range is obtained based on the actual measured error value and adjustment.

[0195] When starting the system, you need to set a preset value for the CAN baud rate of the indoor air conditioner unit (e.g., set the preset value to 20Kbps).

[0196] The baud rate calculation formula is as follows:

[0197] BT=T SEG1 +T SEG2= ((SEG_1+2)+(SEG_2+1))×TQ, where BT represents bit time (bit time is the reciprocal of baud rate), SEG1 represents the first target phase buffer segment, SEG2 represents the second target phase buffer segment, SEG_1 represents the first reference phase buffer segment, SEG_2 represents the second reference phase buffer segment, and T represents time.

[0198] It should be noted that the SYNC_SEG segment in the above formula is a hardware identification transition bit and is not included in the baud rate calculation formula, so the PROP_SEG segment is (2+1)×TQ=3TQ.

[0199] The reference value ranges for SEG_1, SEG_2, and SJW_1 in the above baud rate calculation formula are as follows:

[0200] 0 ≤ SEG_1 ≤ 63, 0 ≤ SEG_2 ≤ 7, 0 ≤ SJW_1 ≤ 7, and SEG_2 + 1 ≤ SEG_1, SJW_1 ≤ SEG_2. Here, SJW_1 represents the reference resynchronization compensation width, which is the design range given by the chip, as shown in the table below:

[0201]

[0202] Therefore, based on the above baud rate calculation formula, and according to the time quantum TQ, the baud rate preset value 1 / BT, and the reference value range (SEG_1, SEG_2, SJW_1), the first target phase buffer segment SEG1, the second target phase buffer segment SEG2, and the first value range of the target resynchronization compensation width SJW are obtained.

[0203] For example, in step 720 above, the step of controlling the register to send data based on the value range includes:

[0204] Step 721: Based on the first value range, take the set values ​​of the first target phase buffer segment SEG1, the second target phase buffer segment SEG2, and the target resynchronization compensation width SJW and write them into the register (also known as the baud rate register BT).

[0205] The registers include a transmit register and a receive register, and the transmit register may also include a main transmit register and a secondary transmit register.

[0206] Step 722: Set the transmit register to CAN transmit data mode and set the corresponding receive register to CAN receive data mode.

[0207] Step 723: Monitor the CAN bus for CAN communication data at preset time intervals. If no communication data is found, proceed to step 724; otherwise, proceed to step 725.

[0208] Step 724: If no CAN communication data is found, switch the polarity of the CAN bus and return to step 723 to continue listening.

[0209] Step 725: If CAN communication data exists, the transceiver controller writes the received CAN communication data into the transmit register and controls the transmit register to transmit the data.

[0210] For example, in step 720 above, the step of reading the transmission status information of the register to obtain the success rate includes:

[0211] Step 726: Read the transmission status information of the transmission register, calculate the success rate based on the number of data transmitted and the number of data successfully transmitted within the time window, and calculate the error value based on the success rate.

[0212] Specifically, the criteria for determining whether data was sent successfully are as follows:

[0213]

[0214] The formulas for calculating the success rate and error value are as follows:

[0215] Fm = Tount1 / Tcount0 * 100%;

[0216] △Fm=100%-Fm;

[0217] Where Fm represents the success rate, Tount1 represents the number of data successfully sent, Tcount0 represents the number of data sent, and △Fm represents the error value.

[0218] For example, in step 730 above, the step of adjusting the values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width according to the success rate to obtain the optimal baud rate setting includes:

[0219] Step 731: Based on the error value and the preset baud rate value, and according to the baud rate calculation formula, increase the first target phase buffer segment and the second target phase buffer segment, and then decrease the time quantum to perform fuzzy adjustment.

[0220] For example, assuming BT is a baud rate of 20K, the analog-to-digital conversion is adjusted based on the error value ΔFm, for example, by positively increasing the first target phase buffer segment and the second target phase buffer segment, thereby decreasing the time quantum, i.e., SEG1+, SEG2+, TQ-.

[0221] Step 732: Based on the result of the fuzzy adjustment, determine whether the error value has decreased. If the error value has increased, proceed to step 733; if the error value has decreased, proceed to step 734.

[0222] Step 733: If the error value increases, then adjust the first target phase buffer segment and the second target phase buffer segment according to the baud rate calculation formula, and then increase the time quantum for fuzzy adjustment.

[0223] For example, if the error value increases, it indicates that the direction of the fuzz adjustment in step 731 is incorrect, and a positive downward fuzz adjustment should be performed, which lowers the first target phase buffer segment and the second target phase buffer segment and then increases the time quantum, namely SEG1-, SEG2-, TQ+.

[0224] Step 734: Perform proportional-integral-derivative (PID) adjustment that keeps the time quantum constant according to the fuzzy adjustment method that can reduce the error value, so as to obtain the adjusted values ​​of the second target phase buffer segment and the target resynchronization compensation width.

[0225] It should be noted that by obtaining the adjustment values ​​of the adjusted second target phase buffer segment and the target resynchronization compensation width, the adjustment value of the adjusted first target phase buffer segment can also be obtained.

[0226] Step 735: Based on the adjustment value, determine the second value range for the second target phase buffer segment and the target resynchronization compensation width. Specifically:

[0227] First, assume the deviation of the clock frequency from the expected frequency value is the reference clock error (Δf). FCLK,max / min represents the maximum or minimum reference clock frequency, and FCLK,rat represents the rated reference clock frequency. The clock cycle will also have an error. TSCL,min represents the minimum system clock cycle, TSCL,max represents the maximum system clock cycle, and TSCL,rat represents the rated system clock cycle. Since Δf << 1, an approximate value can be used.

[0228] TSCL,min=(TSCL,rat) / (1+Δf)≈TSCL,rat×(1-Δf);

[0229] TSCL,max=(TSCL,rat) / (1-Δf)≈TSCL,rat×(1+Δf).

[0230] Secondly, calculate the transmission delay error. The transmission delay time is determined by the physical bus delay (tBUS), the bus driver delay (Ttran), and the transmission delay of other devices (Toth). Other devices include communication controllers, isolation mechanisms, etc.

[0231] tprop=2×(tBUS+ttran+toth);

[0232] The scalar value of transmission delay PROP = tprop / fcan_clk.

[0233] Then, calculate the scalar value of the bit period (NBT) =

[0234] Tbit / TSCL=SYNC_SEG+TSEG1+TSEG2;

[0235]

[0236] SJW max =4;

[0237] TSEG2 min =MAX{2,SJW};

[0238]

[0239] Δf is obtained through chip frequency oscillator calibration calculation, that is, through chip clock calibration calculation.

[0240] For example, in step 730 above, the step of adjusting the values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width according to the success rate to obtain the optimal baud rate setting value further includes:

[0241] Step 736: Based on the second value range, assign values ​​to the second target phase buffer segment and the target resynchronization compensation width.

[0242] For example, the second range of values ​​for determining the second target phase buffer segment and the target resynchronization compensation width is: SEG2 = 1, 2, 3, SJW = 1, 2, 3; then

[0243] When SEG2 = 1, iterate through SJW;

[0244] When SEG2 = 2, iterate through SJW;

[0245] When SEG2=3, traverse SJW.

[0246] The purpose of traversal is to select the set of values ​​with the smallest error (e.g., an error of 0%) from the traversal results and assign it to the register.

[0247] Step 737: Based on the assigned value, determine whether the error value has decreased and whether it is within the adjustment period of the optimal baud rate setting.

[0248] If the error value decreases and is within the adjustment period of the optimal baud rate setting, proceed to step 738; otherwise, return to step 737.

[0249] Step 738: If the error value decreases and is within the adjustment period of the optimal baud rate setting, then when the error value is lower than or equal to the first preset threshold (for example, the first preset threshold is 0%), the first target phase buffer segment, the second target phase buffer segment, the target resynchronization compensation width, and the time quantum are determined to be the target assignment.

[0250] If a set of values ​​with an error of 0% is found in the traversal results, then this set of values ​​is used as the target value and assigned to the register.

[0251] Step 739: Based on the target value, obtain the optimal baud rate setting value according to the baud rate calculation formula.

[0252] For example, after performing step 739, the control method for the multi-split air conditioning system further includes:

[0253] Step 740: Determine whether the adjustment period for determining the optimal baud rate setting exceeds the second preset threshold (e.g., the second preset threshold is 30 seconds).

[0254] If the adjustment period for the optimal baud rate setting exceeds the second preset threshold, then return to step 736 above, that is, assign values ​​to the second target phase buffer segment and the target resynchronization compensation width based on the second value range. In other words, this invention adjusts the baud rate setting every second preset threshold to ensure reliable data transmission.

[0255] Understandably, in the CAN communication protocol, the communication baud rate, the sampling position and number of samples per bit cycle can all be set by the user. The design philosophy of CAN is to provide users with flexibility in optimizing network communication performance during practical applications. To optimize performance by setting the baud rate, it's necessary to understand the relationship between bit timing parameters, reference clock errors, and signal delays within the system. If the sampling position within a bit cycle is further back, a larger signal transmission delay can be tolerated, and correspondingly, the bus transmission distance can be extended; conversely, if the sampling position within a cycle is closer to the middle, reference clock errors between system nodes can be tolerated. However, this is clearly contradictory. To reconcile this contradiction, the bit timing parameters need to be adaptively and dynamically optimized.

[0256] Therefore, by optimizing the baud rate setting in the control method of the multi-split air conditioning system described in this invention, even when the number of indoor slave nodes reaches a preset value (e.g., 80) or more, the probability of indoor slave nodes going offline can be reduced in the bus system, and when multiple nodes are transmitting data concurrently, the probability of data delay or even loss of indoor slave nodes can also be reduced.

[0257] The following describes the multi-split air conditioner node communication system provided by the present invention. The multi-split air conditioner node communication system described below can be referred to in correspondence with the multi-split air conditioner node communication method described above.

[0258] Please refer to Figure 8 , Figure 8 This is a schematic diagram of the structure of the multi-split air conditioner node communication system provided by the present invention. A multi-split air conditioner node communication system has multiple air conditioner nodes, each including a master node and multiple slave nodes. The multiple slave nodes include multiple outdoor slave nodes and multiple indoor slave nodes. The multi-split air conditioner node communication system 800 includes a system initialization module 810 and a system management module 820, wherein...

[0259] The system initialization module 810 is used for:

[0260] The host node assigns an IP address to each slave node and stores the IP address of each slave node in the node registration table;

[0261] The system management module 820 is used for:

[0262] The host node periodically initiates communication requests to each slave node and requires each slave node to respond to the communication request with its own node information, which includes IP address information assigned by the host node and attribute information of the slave node.

[0263] The master node performs corresponding management operations based on the feedback from each slave node. These management operations include adding a slave node, deleting a slave node, and modifying a slave node.

[0264] For example, the system initialization module 810 is further configured to:

[0265] When the multi-split air conditioning system is powered on for the first time, CAN configuration is performed on the master node and each slave node. The CAN configuration includes baud rate configuration, data transmission and reception configuration, and data transmission configuration.

[0266] For example, the system initialization module 810 is further configured to:

[0267] The master node periodically sends a communication start frame to each slave node on the CAN bus.

[0268] Determine whether each slave node has received the communication start frame in this round of communication;

[0269] If each slave node receives the communication start frame, then each slave node sends a request frame to the master node to request its own IP address;

[0270] If a slave node fails to receive the communication start frame, the slave node that has not received the communication start frame will switch its CAN polarity every preset time period and continue to listen for whether it has received the communication start frame.

[0271] For example, the system initialization module 810 is further configured to:

[0272] Determine whether the host node has received an IP address request frame from each slave node;

[0273] If the host node receives the request frame from each slave node, it sends a response frame to each slave node to allocate the corresponding IP address;

[0274] If the host node does not receive an application frame from a slave node, the slave node will continue to send application frames to the host node every preset time interval to apply for its own IP address.

[0275] For example, the system initialization module 810 is further configured to:

[0276] After receiving the IP address assigned to it by the master node, the slave node broadcasts its own IP address to the CAN bus via a broadcast frame.

[0277] After receiving the IP address broadcast by each slave node, the host node registers and stores the IP address of each slave node in the node registration table to complete the allocation of IP address to each slave node during the system initialization phase.

[0278] For example, the system management module 820 is further configured to:

[0279] If the host node does not receive node information from a slave node in the node registration table within a preset time period, the slave node is marked as offline to complete the operation of modifying the slave node.

[0280] If the host node receives node information from each slave node in the node registration table, it indicates that the host node and each slave node can communicate normally, and the host node continues to listen for whether the host node initiates a communication request to each slave node.

[0281] For example, the system management module 820 is further configured to:

[0282] When a new slave node is connected to the multi-split air conditioning system, the new slave node is configured to listen to the master node on the CAN bus.

[0283] Determine whether the newly added slave node has received the communication start frame initiated by the master node to each slave node in this round of communication;

[0284] If the newly added slave node does not receive the communication start frame, it switches its own CAN polarity to continue listening to see if the communication start frame has been received.

[0285] If the newly added slave node receives the communication start frame, it sends a request frame to the host node to request its own IP address;

[0286] The host node sends a response frame to the newly added slave node to allocate the corresponding IP address;

[0287] After receiving the IP address, the newly added slave node broadcasts its own IP address to the CAN bus, and the master node stores it in the node registration table to complete the operation of adding a slave node.

[0288] For example, the system management module 820 is further configured to:

[0289] When the host node receives a node deletion command from the central controller or cloud server, the host node sends a node deletion command to the specified slave node.

[0290] When the slave node receives the node deletion command frame sent by the master node, it clears its own IP address and replies to the master node by sending a deletion frame, indicating that its IP address is 0 and the attribute information of the slave node.

[0291] After receiving the deletion frame, the host node marks the slave node as deleted to complete the deletion operation.

[0292] For example, the system management module 820 is further configured to:

[0293] When a slave node marked as offline or deleted by the host node needs to re-enter the multi-split air conditioning system, it needs to be powered on and reset.

[0294] Execute the process of adding a new slave node, or connect to a multi-split air conditioning system that has not undergone system initialization.

[0295] For example, the system initialization module 810 is further configured to:

[0296] Based on the preset values ​​of prescaler, CAN clock frequency and baud rate set in the register, the value ranges of the first target phase buffer segment, the second target phase buffer segment and the target resynchronization compensation width are obtained.

[0297] The register is controlled to send data based on the value range, and the sending status information of the register is read to obtain the success rate;

[0298] The values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width are adjusted according to the success rate to obtain the optimal baud rate setting.

[0299] For example, the system initialization module 810 is further configured to:

[0300] The time quantum is obtained based on the prescaler set in the register and the CAN clock frequency;

[0301] Based on the preset values ​​of time quantum and baud rate, and according to the baud rate calculation formula, the first value range of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width is obtained;

[0302] The formula for calculating this time quantum is:

[0303] TQ = (PRESC + 1) / f can_clk TQ represents time quantum, PRESC represents the prescaler set by the register, and f can_clk Indicates the CAN clock frequency;

[0304] The baud rate calculation formula is as follows:

[0305] BT=T SEG1 +T SEG2 =((SEG_1+2)+(SEG_2+1))×TQ, BT means

[0306] Baud rate, SEG1 represents the first target phase buffer segment, SEG2 represents the second target phase buffer segment, SEG_1 represents the first reference phase buffer segment, SEG_2 represents the second reference phase buffer segment, and T represents time.

[0307] For example, the system initialization module 810 is further configured to:

[0308] The first reference phase buffer segment and the second reference phase buffer segment are set through the first reference phase buffer segment bit and the second reference phase buffer segment bit in the register, and the corresponding reference value range is:

[0309] 0≤SEG_1≤63, 0≤SEG_2≤7, 0≤SJW_1≤7, and

[0310] SEG_2+1≤SEG_1,SJW_1≤SEG_2,SJW_1 represents the reference resynchronization compensation width;

[0311] Based on the baud rate calculation formula, and according to the time quantum, the preset baud rate value, and the reference value range, the first target phase buffer segment, the second target phase buffer segment, and the first value range of the target resynchronization compensation width are obtained.

[0312] For example, the system initialization module 810 is further configured to:

[0313] Based on the first value range, the set values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width are written into the register, which includes a transmit register and a receive register.

[0314] Set the transmit register to CAN transmit data mode and the corresponding receive register to CAN receive data mode;

[0315] Monitor the CAN bus for CAN communication data at preset time intervals;

[0316] If no CAN communication data is available, the polarity of the CAN bus is switched and listening continues; if CAN communication data is available, the received CAN communication data is written into the transmit register and the transmit register is controlled to transmit the data.

[0317] For example, the system initialization module 810 is further configured to:

[0318] Read the transmission status information of the transmission register, calculate the success rate based on the number of data transmitted and the number of data successfully transmitted within the time window, and calculate the error value based on the success rate;

[0319] The formulas for calculating the success rate and error value are as follows:

[0320] Fm = Tount1 / Tcount0 * 100%;

[0321] △Fm=100%-Fm;

[0322] Where Fm represents the success rate, Tount1 represents the number of data successfully sent, Tcount0 represents the number of data sent, and △Fm represents the error value.

[0323] For example, the system initialization module 810 is further configured to:

[0324] Based on the error value and the preset baud rate value, and according to the baud rate calculation formula, the first target phase buffer segment and the second target phase buffer segment are increased, and the time quantum is decreased to perform fuzzy adjustment;

[0325] Based on the result of the fuzzy adjustment, it is determined whether the error value has decreased;

[0326] If the error value increases, the first target phase buffer segment and the second target phase buffer segment are lowered and the time quantum is increased according to the baud rate calculation formula to perform fuzzy adjustment.

[0327] Based on the fuzzy adjustment method that can reduce the error value, proportional-integral-derivative adjustment is performed while keeping the time quantum constant, so as to obtain the adjusted values ​​of the second target phase buffer segment and the target resynchronization compensation width;

[0328] Based on the adjustment value, a second range of values ​​for the second target phase buffer segment and the target resynchronization compensation width is determined.

[0329] For example, the system initialization module 810 is further configured to:

[0330] Based on the second value range, assign values ​​to the second target phase buffer segment and the target resynchronization compensation width;

[0331] Based on the assigned value, determine whether the error value has decreased and whether it is within the adjustment period of the optimal baud rate setting;

[0332] If the error value decreases and is within the adjustment period of the optimal baud rate setting, then when the error value is lower than or equal to the first preset threshold, the first target phase buffer segment, the second target phase buffer segment, the target resynchronization compensation width, and the time quantum are determined to be the target assignment.

[0333] The optimal baud rate setting value is obtained according to the target value and the baud rate calculation formula.

[0334] For example, the system initialization module 810 is further configured to:

[0335] Determine whether the adjustment period for determining the optimal baud rate setting exceeds the second preset threshold;

[0336] If it is determined that the adjustment period of the most baud rate setting exceeds the second preset threshold, then return to the step of assigning values ​​to the second target phase buffer segment and the target resynchronization compensation width based on the second value range.

[0337] It should be noted that the multi-split air conditioning node communication system provided in this embodiment of the invention can implement all the method steps implemented in the above method embodiment and achieve the same technical effect. Therefore, the parts and beneficial effects that are the same as those in the method embodiment will not be described in detail here.

[0338] Figure 9 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 9 As shown, the electronic device may include: a processor 910, a communication interface 920, a memory 930, and a communication bus 940, wherein the processor 910, the communication interface 920, and the memory 930 communicate with each other through the communication bus 940. The processor 910 can call logical instructions in the memory 930 to execute a multi-split air conditioning node communication method, which includes a system initialization step and a management entry step, wherein...

[0339] The system initialization steps include:

[0340] The host node assigns an IP address to each slave node and stores the IP address of each slave node in the node registration table;

[0341] The system management steps include:

[0342] The host node periodically initiates communication requests to each slave node and requires each slave node to respond to the communication request with its own node information, which includes IP address information assigned by the host node and attribute information of the slave node.

[0343] The master node performs corresponding management operations based on the feedback from each slave node. These management operations include adding a slave node, deleting a slave node, and modifying a slave node.

[0344] Furthermore, the logical instructions in the aforementioned memory 930 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0345] On the other hand, the present invention also provides a computer program product, the computer program product including a computer program stored on a non-transitory computer-readable storage medium, the computer program including program instructions, and when the program instructions are executed by a computer, the computer is able to execute the multi-split air conditioning node communication method provided by the above methods.

[0346] In another aspect, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to perform the multi-split air conditioning node communication methods provided above.

[0347] The present invention provides an electronic device, a computer program product, and a processor-readable storage medium, wherein the computer program stored thereon enables the processor to implement all the method steps implemented in the above method embodiments and achieve the same technical effect. Here, the parts that are the same as those in the method embodiments and the beneficial effects will not be described in detail.

[0348] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0349] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0350] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A communication method for multi-split air conditioning nodes, applied to a multi-split air conditioning system with multiple air conditioning nodes, wherein each air conditioning node includes a master node and multiple slave nodes, the multiple slave nodes including multiple outdoor slave nodes and multiple indoor slave nodes, characterized in that, The method includes system initialization steps and system management steps, wherein, The system initialization steps include: The host node assigns an IP address to each slave node and stores the IP address of each slave node in the node registration table; The system management steps include: The host node periodically initiates communication requests to each slave node and requires each slave node to respond to the communication request with its own node information, which includes IP address information assigned by the host node and attribute information of the slave node. The master node performs corresponding management operations based on the feedback from each slave node. These management operations include adding a slave node, deleting a slave node, and modifying a slave node. Before the host node assigns an IP address to each slave node, the system initialization steps further include: When the multi-split air conditioning system is powered on for the first time, CAN configuration is performed on the master node and each slave node. The CAN configuration includes baud rate configuration, data transmission and reception configuration, and data transmission configuration. The steps for configuring the master node and each slave node via CAN when the multi-split air conditioning system is powered on for the first time include: Based on the preset values ​​of prescaler, CAN clock frequency and baud rate set in the register, the value ranges of the first target phase buffer segment, the second target phase buffer segment and the target resynchronization compensation width are obtained. The register is controlled to send data based on the value range, and the sending status information of the register is read to obtain the success rate; The values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width are adjusted according to the success rate to obtain the optimal baud rate setting. The steps for the host node to assign an IP address to each slave node include: The master node periodically sends a communication start frame to each slave node on the CAN bus. Determine whether each slave node has received the communication start frame in this round of communication; If each slave node receives the communication start frame, then each slave node sends a request frame to the master node to request its own IP address; If a slave node fails to receive the communication start frame, the slave node that has not received the communication start frame will switch its CAN polarity every preset time period and continue to listen for whether it has received the communication start frame.

2. The multi-split air conditioning node communication method according to claim 1, characterized in that, The step of assigning an IP address to each slave node by the host node also includes: Determine whether the host node has received an IP address request frame from each slave node; If the host node receives the request frame from each slave node, it sends a response frame to each slave node to allocate the corresponding IP address; If the host node does not receive an application frame from a slave node, the slave node will continue to send application frames to the host node every preset time interval to apply for its own IP address.

3. The multi-split air conditioning node communication method according to claim 2, characterized in that, The step of storing the IP address of each slave device in the node registration table includes: After receiving the IP address assigned to it by the master node, the slave node broadcasts its own IP address to the CAN bus via a broadcast frame. After receiving the IP address broadcast by each slave node, the host node registers and stores the IP address of each slave node in the node registration table to complete the allocation of IP address to each slave node during the system initialization phase.

4. The multi-split air conditioning node communication method according to claim 1, characterized in that, The steps by which the master node performs corresponding management operations based on feedback from each slave node include: If the host node does not receive node information from a slave node in the node registration table within a preset time period, the slave node is marked as offline to complete the operation of modifying the slave node. If the host node receives node information from each slave node in the node registration table, it indicates that the host node and each slave node can communicate normally, and the host node continues to listen for whether the host node initiates a communication request to each slave node.

5. The multi-split air conditioning node communication method according to claim 1, characterized in that, The steps for the master node to perform corresponding management operations based on feedback from each slave node also include: When a new slave node is connected to the multi-split air conditioning system, the new slave node is configured to listen to the master node on the CAN bus. Determine whether the newly added slave node has received the communication start frame initiated by the master node to each slave node in this round of communication; If the newly added slave node does not receive the communication start frame, it switches its own CAN polarity to continue listening to see if the communication start frame has been received. If the newly added slave node receives the communication start frame, it sends a request frame to the host node to request its own IP address; The host node sends a response frame to the newly added slave node to allocate the corresponding IP address; After receiving the IP address, the newly added slave node broadcasts its own IP address to the CAN bus, and the master node stores it in the node registration table to complete the operation of adding a slave node.

6. The multi-split air conditioning node communication method according to claim 1, characterized in that, The steps for the master node to perform corresponding management operations based on feedback from each slave node also include: When the host node receives a node deletion command from the central controller or cloud server, the host node sends a node deletion command to the specified slave node. When the slave node receives the node deletion command frame sent by the master node, it clears its own IP address and replies to the master node by sending a deletion frame, indicating that its IP address is 0 and the attribute information of the slave node. After receiving the deletion frame, the host node marks the slave node as deleted to complete the deletion operation.

7. The multi-split air conditioning node communication method according to claim 1, characterized in that, The steps for the master node to perform corresponding management operations based on feedback from each slave node also include: When a slave node marked as offline or deleted by the host node needs to re-enter the multi-split air conditioning system, it needs to be powered on and reset. Execute the process of adding a new slave node, or connect to a multi-split air conditioning system that has not undergone system initialization.

8. The multi-split air conditioning node communication method according to claim 1, characterized in that, The step of obtaining the value ranges of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width based on the prescaler, CAN clock frequency, and baud rate preset values ​​set in the register includes: The time quantum is obtained based on the prescaler set in the register and the CAN clock frequency; Based on the preset values ​​of time quantum and baud rate, and according to the baud rate calculation formula, the first value range of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width is obtained; The formula for calculating this time quantum is: TQ=(PRESC+1) / f can_clk TQ represents time quantum, PRESC represents the prescaler set by the register, and f can_clk Indicates the CAN clock frequency; The baud rate calculation formula is as follows: BT=T SEG1 +T SEG2 = ((SEG_1+2)+(SEG_2+1))×TQ, where BT represents the baud rate, SEG1 represents the first target phase buffer segment, SEG2 represents the second target phase buffer segment, SEG_1 represents the first reference phase buffer segment, SEG_2 represents the second reference phase buffer segment, and T represents time.

9. The multi-split air conditioning node communication method according to claim 8, characterized in that, The step of obtaining the first value range of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width based on the preset values ​​of the time quantum and baud rate, and according to the baud rate calculation formula, includes: The first reference phase buffer segment and the second reference phase buffer segment are set through the first reference phase buffer segment bit and the second reference phase buffer segment bit in the register, and the corresponding reference value range is: 0≤SEG_1≤63, 0≤SEG_2≤7, 0≤SJW_1≤7, and SEG_2+1≤SEG_1,SJW_1≤SEG_2,SJW_1 represents the reference resynchronization compensation width; Based on the baud rate calculation formula, and according to the time quantum, the preset baud rate value, and the reference value range, the first value range of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width is obtained.

10. The multi-split air conditioning node communication method according to claim 9, characterized in that, The step of controlling the register to send data based on the value range includes: Based on the first value range, the set values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width are written into the register, which includes a transmit register and a receive register. Set the transmit register to CAN transmit data mode and the corresponding receive register to CAN receive data mode; Monitor the CAN bus for CAN communication data at preset time intervals; If no CAN communication data is available, the polarity of the CAN bus is switched and listening continues; if CAN communication data is available, the received CAN communication data is written into the transmit register and the transmit register is controlled to transmit the data.

11. The multi-split air conditioning node communication method according to claim 10, characterized in that, The step of reading the transmission status information of the register to obtain the success rate includes: Read the transmission status information of the transmission register, calculate the success rate based on the number of data transmitted and the number of data successfully transmitted within the time window, and calculate the error value based on the success rate; The formulas for calculating the success rate and error value are as follows: Fm = Tount1 / Tcount0 * 100%; △Fm = 100% - Fm; Where Fm represents the success rate, Tount1 represents the number of data successfully sent, Tcount0 represents the number of data sent, and △Fm represents the error value.

12. The multi-split air conditioning node communication method according to claim 11, characterized in that, The step of adjusting the values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width according to the success rate to obtain the optimal baud rate setting includes: Based on the error value and the preset baud rate value, and according to the baud rate calculation formula, the first target phase buffer segment and the second target phase buffer segment are increased, and the time quantum is decreased to perform fuzzy adjustment; Based on the result of the fuzzy adjustment, it is determined whether the error value has decreased; If the error value increases, the first target phase buffer segment and the second target phase buffer segment are lowered and the time quantum is increased according to the baud rate calculation formula to perform fuzzy adjustment. Based on the fuzzy adjustment method that can reduce the error value, proportional-integral-derivative adjustment is performed while keeping the time quantum constant, so as to obtain the adjusted values ​​of the second target phase buffer segment and the target resynchronization compensation width; Based on the adjustment value, a second range of values ​​for the second target phase buffer segment and the target resynchronization compensation width is determined.

13. The multi-split air conditioning node communication method according to claim 12, characterized in that, The step of adjusting the values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width according to the success rate to obtain the optimal baud rate setting also includes: Based on the second value range, assign values ​​to the second target phase buffer segment and the target resynchronization compensation width; Based on the assigned value, determine whether the error value has decreased and whether it is within the adjustment period of the optimal baud rate setting; If the error value decreases and is within the adjustment period of the optimal baud rate setting, then when the error value is lower than or equal to the first preset threshold, the first target phase buffer segment, the second target phase buffer segment, the target resynchronization compensation width, and the time quantum are determined to be the target assignment. The optimal baud rate setting value is obtained according to the target value and the baud rate calculation formula.

14. The multi-split air conditioning node communication method according to claim 13, characterized in that, After the step of determining the optimal baud rate setting value according to the baud rate calculation formula based on the target assignment, the method further includes: Determine whether the adjustment period for determining the optimal baud rate setting exceeds the second preset threshold; If it is determined that the adjustment period of the most baud rate setting exceeds the second preset threshold, then return to the step of assigning values ​​to the second target phase buffer segment and the target resynchronization compensation width based on the second value range.

15. A multi-split air conditioning node communication system, comprising multiple air conditioning nodes, each air conditioning node including a master node and multiple slave nodes, the multiple slave nodes including multiple outdoor slave nodes and multiple indoor slave nodes, characterized in that, The system includes a system initialization module and a system management module, wherein, The system initialization module is used for: The host node assigns an IP address to each slave node and stores the IP address of each slave node in the node registration table; The system management module is used for: The host node periodically initiates communication requests to each slave node and requires each slave node to respond to the communication request with its own node information, which includes IP address information assigned by the host node and attribute information of the slave node. The master node performs corresponding management operations based on the feedback from each slave node. These management operations include adding a slave node, deleting a slave node, and modifying a slave node. The system initialization module is also used for: When the multi-split air conditioning node communication system is powered on for the first time, CAN configuration is performed on the master node and each slave node. The CAN configuration includes baud rate configuration, data transmission and reception configuration, and data transmission configuration. The system initialization module is also used for: Based on the preset values ​​of prescaler, CAN clock frequency and baud rate set in the register, the value ranges of the first target phase buffer segment, the second target phase buffer segment and the target resynchronization compensation width are obtained. The register is controlled to send data based on the value range, and the sending status information of the register is read to obtain the success rate; The values ​​of the first target phase buffer segment, the second target phase buffer segment, and the target resynchronization compensation width are adjusted according to the success rate to obtain the optimal baud rate setting. The system initialization module is also used for: The master node periodically sends a communication start frame to each slave node on the CAN bus. Determine whether each slave node has received the communication start frame in this round of communication; If each slave node receives the communication start frame, then each slave node sends a request frame to the master node to request its own IP address; If a slave node fails to receive the communication start frame, the slave node that has not received the communication start frame will switch its CAN polarity every preset time period and continue to listen for whether it has received the communication start frame.

16. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the multi-split air conditioning node communication method as described in any one of claims 1 to 14.

17. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the multi-split air conditioning node communication method as described in any one of claims 1 to 14.

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