CN112363479B - A digital communication transmission method and system between field devices - Google Patents

Abstract

The invention relates to a digital communication transmission method and system between field devices. The method includes: using a device instruction to generate a device data combination instruction; in a communication correction mode, using the communication correction instruction to configure the device data combination instruction to determine the configured combination instruction; Whether the special broadcast function bit allows the special broadcast function of the configured combined instruction, if so, perform bidirectional data transmission according to the special broadcast function; if not, use the configured bidirectional data transmission function of the combined instruction to perform bidirectional data transmission data transmission. The invention can greatly improve the working efficiency of the system and the utilization rate of the communication bandwidth.

Description

A digital communication transmission method and system between field devices

technical field

The invention relates to the field of digital communication, in particular to a method and system for digital communication transmission between field devices.

Background technique

Fieldbus (Fieldbus) is an industrial data bus that has developed rapidly in recent years. It mainly solves the digital communication between field devices such as intelligent instruments, controllers, and actuators in industrial fields, as well as these field control devices and advanced control systems. The problem of information transmission between them, usually the field bus is a half-duplex bus, and the communication bandwidth utilization rate of the existing communication protocol is very low.

1. For example, in a single-master structure, the master device sends commands and the slave device sends data. Assuming that there are ten data formats in the device, seven of them need to be used. According to the existing protocol, seven commands must be sent respectively, These seven pieces of data are obtained separately, and the operation is complicated and inefficient.

2. In fieldbus communication, if the master device needs to send data to the slave device, it needs to send an instruction to send data; if the master device needs to obtain data from the slave device, it needs to send an instruction to receive data. Sending and receiving commands cannot be sent at the same time, they need to be sent separately, and the operation process is cumbersome.

3. The existing normal broadcast packet is that the master device sends a command to all slave devices, each slave device receives the same command, and the slave device will not distinguish the command, and all slave devices will perform the same operation, so this This method makes it difficult to achieve personalized control of a single slave device.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a digital communication transmission method and system between field devices, so as to solve the problem of low utilization rate of communication bandwidth in the existing communication transmission process.

For achieving the above object, the present invention provides the following scheme:

A digital communication transmission method between field devices, comprising:

Use device instructions to generate device data combination instructions; the device instructions include device parameter setting instructions, slave device operation mode, last command execution status instructions, device address instructions, special mode instructions, storage format correction instructions and combined data exchange instructions ;

In the communication correction mode, the device data combination instruction is configured by the communication correction instruction, and the configured combination instruction is determined; the communication correction instruction includes a global parameter configuration instruction and a single parameter configuration instruction; the configured combination instruction Used to receive device data while sending device data;

Judging whether the special broadcast function bit in the configured combined instruction allows the special broadcast function of the configured combined instruction, and obtains a first judgment result;

If the first judgment result indicates that the special broadcast function bit in the configured combination command allows the special broadcast function of the configured combination command, bidirectional data transmission is performed according to the special broadcast function; the special broadcast function The function is used to receive the response packet in one of the configured combined instructions and continue to respond;

If the first judgment result indicates that the special broadcast function bit in the configured combination command does not allow the special broadcast function of the configured combination command, use the bidirectional data transmission function of the configured combination command to perform Bidirectional data transmission; the bidirectional data transmission function is used to send data and receive data simultaneously in one of the configured combined instructions.

Optionally, in the communication correction mode, use a communication correction instruction to configure the device data combination instruction, and determine the configured combination instruction, which specifically includes:

In the communication correction mode, configure the global parameters in the device data combination instruction:

The first step: configure the channel of the device data combination command: when the global parameter channel selection bit is set to 0, the configured combination command is stored in the combination command packet 0; when the channel selection bit is set to 1 , the configured combined instruction is stored in combined instruction data packet 1;

The second step: configure the length of special broadcast data: after the special broadcast packet of the device data combination instruction is enabled, use different fields of the special broadcast packet as data of different devices;

Step 3: Configure the mapping selection bits for read data and write data: in the read state, the master device sends the configured combined command to the slave device and reads the slave device data; in the write state, the master device sends After the slave device sends the combined command that the configuration is completed, the master device data is written to the slave device;

Step 4: Configure the number of data types: Set the number of configured data types to n, then there are n data combinations in the combination instruction after the configuration is completed;

After configuring the global parameters, configure the first n single parameters:

Step 1: Configure the data type: The data type adopts 6-bit encoding. When the communication system is lower than the 6-bit encoding, the data type is configured by indirect reference data type;

Step 2: Configure the initial data channel of the data;

Step 3: Configure the number of data channels;

When the single parameter configuration is completed, the configured combined command is determined.

Optionally, the bidirectional data transmission according to the special broadcast function specifically includes:

When the command received by the device is a sending data command and the device address is a broadcast address, the current device data is determined according to the data channel and data length of the configured combined command and the length of the special broadcast data in the storage format correction command; The data length is an integer multiple of the special broadcast data length; the device is a master device or a slave device;

When the RxTx function in the special mode command is enabled, the current device data is transmitted and the Rx response packet is used to continuously respond; the Rx response packet contains the configured combined command for reading data; Rx is Receive, Tx is send.

Optionally, the bidirectional data transmission using the bidirectional data transmission function of the configured combined command specifically includes:

When the device is addressed and the device receives a Tx command, it returns an Rx response packet.

Optionally, in the bidirectional data transmission process, when the transmission quantity is higher than the transmission quantity threshold, an isochronous transmission mode is used to perform bidirectional data transmission.

A digital communication transmission system between field devices, comprising:

The device data combination instruction generation module is used to generate the device data combination instruction by using the device instruction; the device instruction includes the device parameter setting instruction, the slave device operation mode, the last command execution status instruction, the device address instruction, the special mode instruction, Store format correction instructions and combined data exchange instructions;

The configuration module is used to configure the device data combination instruction by using the communication correction instruction in the communication correction mode, and determine the configured combination instruction; the communication correction instruction includes a global parameter configuration instruction and a single parameter configuration instruction; the The configured combined command is used to receive device data while sending device data;

a first judgment module, configured to judge whether the special broadcast function bit in the configured combined instruction allows the special broadcast function of the configured combined instruction, and obtain a first judgment result;

A special broadcast packet transmission module, configured to perform the special broadcast function according to the special broadcast function if the first judgment result indicates that the special broadcast function bit in the configured combination command allows the special broadcast function of the configured combination command Two-way data transmission; the special broadcast function is used to receive a response packet in a combined command after the configuration and continue to respond;

The bidirectional data transmission module is used for, if the first judgment result indicates that the special broadcast function bit in the configured combination instruction does not allow the special broadcast function of the configured combination instruction, use the configured combination instruction The bidirectional data transmission function of the instruction performs bidirectional data transmission; the bidirectional data transmission function is used to send data and receive data simultaneously in one of the configured combined instructions.

Optionally, the configuration module specifically includes:

A global parameter configuration unit, configured to configure the global parameters in the device data combination instruction in the communication correction mode:

The first step: configure the channel of the device data combination command: when the global parameter channel selection bit is set to 0, the configured combination command is stored in the combination command packet 0; when the channel selection bit is set to 1 , the configured combined instruction is stored in combined instruction data packet 1;

The second step: configure the length of special broadcast data: after the special broadcast packet of the device data combination instruction is enabled, use different fields of the special broadcast packet as data of different devices;

Step 3: Configure the mapping selection bits for read data and write data: in the read state, the master device sends the configured combined command to the slave device and reads the slave device data; in the write state, the master device sends After the slave device sends the combined command that the configuration is completed, the master device data is written to the slave device;

Step 4: Configure the number of data types: Set the number of configured data types to n, then there are n data combinations in the combination instruction after the configuration is completed;

The single parameter configuration unit is used to configure the first n single parameters after the global parameters are configured:

Step 1: Configure the data type: The data type adopts 6-bit encoding. When the communication system is lower than the 6-bit encoding, the data type is configured by indirect reference data type;

Step 2: Configure the initial data channel of the data;

Step 3: Configure the number of data channels;

When the single parameter configuration is completed, the configured combined command is determined.

Optionally, the special broadcast packet transmission module specifically includes:

The current device data determination unit is used to correct the special data in the command according to the data channel, data length and the storage format of the configured combined command when the command received by the device is a send data command and the device address is a broadcast address. The broadcast data length determines the current device data; the data length is an integer multiple of the special broadcast data length; the device is a master device or a slave device;

The special broadcast packet transmission unit is used to transmit the current device data and use the Rx response packet to continuously respond when the RxTx function in the special mode command is enabled; the Rx response packet contains the read data. The configured combined command; Rx is for receiving, Tx is for sending.

Optionally, the two-way data transmission module specifically includes:

The bidirectional data transmission unit is used to return an Rx response packet when the device is addressed and the device receives a Tx command.

Optionally, in the bidirectional data transmission process, when the transmission quantity is higher than the transmission quantity threshold, an isochronous transmission mode is used to perform bidirectional data transmission.

According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects: the present invention provides a method and system for digital communication transmission between field devices, by configuring the combination instructions of different types of data, the main device only needs to send a combination of The required data can be acquired by the command, or all the data to be sent can be sent by only one combined command. The present invention reduces the number of field bus communications by combining the commands, and can greatly improve the bandwidth utilization rate. , that is, the utilization rate of data;

The present invention uses the bidirectional data transmission technology to carry out bidirectional transmission, and the field bus is no longer limited to a single "one send and one receive" communication mode, but through the combination of sending and receiving commands, the same command can collect data while sending data. function. For example, the master device needs to send data to the slave device, and needs to receive the data collected or returned by the slave device. Now it is no longer necessary to send the data sending command and the data receiving command separately, but only need to send a combined command, which can greatly save the process. time and improve communication efficiency.

At the same time, the normal broadcast of the current fieldbus is that the master device sends data packets to all slave devices. All slave devices receive the same data packets, and each slave device will perform the same operation, which cannot achieve precise control of a single device. ; And the present invention uses special broadcast packet transmission technology to carry out bidirectional transmission, the special broadcast in the present invention is that the master device sends data or instructions to the slave equipment, and the slave equipment receives the same data or instructions, and each slave device will receive the same data or instructions. The part of the data packet or command that belongs to itself, and make corresponding operations. Therefore, the special broadcast packet technology enables the master device to control all different devices through one command, which greatly improves the control efficiency and the utilization of communication bandwidth in on-site communication. Rate.

To sum up, the present invention can combine sending instructions and receiving instructions to realize bidirectional transmission of data, that is, the same instruction collects data while sending data, which greatly simplifies operations and improves the utilization of communication bandwidth. At the same time, allowing different slave devices to accept different data commands in one broadcast command to achieve special broadcast packet support, it can greatly improve the system work efficiency and the utilization of communication bandwidth.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings required in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some of the present invention. In the embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative labor.

Fig. 1 is a single main structure network topology diagram;

Fig. 2 is the flow chart of the field bus communication process;

3 is a flowchart of a digital communication transmission method between field devices provided by the present invention;

Fig. 4 is the data transmission flow chart under the isochronous transmission mode;

FIG. 5 is a structural diagram of a digital communication transmission system between field devices provided by the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The purpose of the present invention is to provide a digital communication transmission method and system between field devices, which can greatly improve the working efficiency of the system and the utilization rate of communication bandwidth.

In order to make the above objects, features and advantages of the present invention more clearly understood, the present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Noun description:

Master Device or Host: The device that plays a leading role in the network, or the device that obtains the bus control right in the bus arbitration, can start or terminate the communication with any other device in the network at any time.

Slave device SalveDevice or Device: A device that is in a slave role in the network, or a device that fails in bus arbitration and does not obtain bus control rights, can complete certain functions by itself, but cannot actively initiate communication with other devices in the network, it must be It is only possible through the master device, and it must be what the master device expects.

The present invention is applicable to a bus network with a single master structure, such as an RS485 bus. Fig. 1 is a network topology diagram of a single main structure, and the network topology is shown in Fig. 1 .

There can only be one master device in this network topology, and there can be one or more slave devices. A communication process of a single master structure includes two parts: addressing/connection and data exchange. The master device can initiate or terminate communication, and only when the bus is idle can the master device initiate the next communication. All data flow is controlled by the master device.

Communication startup is the addressing/connection process. The master device sends a data packet containing the desired address of the device to the bus. The slave device successfully receives the command packet and the address matches, then the communication starts successfully. Figure 2 shows the fieldbus communication The process flow chart is shown in Figure 2. Table 1 is a table of equipment instruction parameters, and the equipment instruction parameters involved in the present invention are shown in Table 1.

Table 1

Fig. 3 is the flow chart of the digital communication transmission method between field devices provided by the present invention, as shown in Fig. 3, a kind of digital communication transmission method between field devices, including:

Step 301: Use the device command to generate the device data combination command; the device command includes the device parameter setting command, the slave device operation mode, the last command execution status command, the device address command, the special mode command, the storage format correction command and the combination. Data exchange instructions.

Step 302: in the communication correction mode, use the communication correction instruction to configure the device data combination instruction, and determine the configured combination instruction; the communication correction instruction includes a global parameter configuration instruction and a single parameter configuration instruction; after the configuration The combined command is used to receive device data at the same time as sending device data.

The step 302 specifically includes:

In the communication correction mode, configure the global parameters in the device data combination instruction:

The first step: configure the channel of the device data combination command: when the global parameter channel selection bit is set to 0, the configured combination command is stored in the combination command packet 0; when the channel selection bit is set to 1 , the configured combined instruction is stored in combined instruction data packet 1;

The second step: configure the length of special broadcast data: after the special broadcast packet of the device data combination instruction is enabled, use different fields of the special broadcast packet as data of different devices;

Step 3: Configure the mapping selection bits for read data and write data: in the read state, the master device sends the configured combined command to the slave device and reads the slave device data; in the write state, the master device sends After the slave device sends the combined command that the configuration is completed, the master device data is written to the slave device;

Step 4: Configure the number of data types: Set the number of configured data types to n, then there are n data combinations in the combination instruction after the configuration is completed;

After configuring the global parameters, configure the first n single parameters:

Step 1: Configure the data type: The data type adopts 6-bit encoding. When the communication system is lower than the 6-bit encoding, the data type is configured by indirect reference data type;

Step 2: Configure the initial data channel of the data;

Step 3: Configure the number of data channels;

When the single parameter configuration is completed, the configured combined command is determined.

In practical applications, the device-related data combination instruction is used in the present invention to combine different data types inside the device, and then packaged and exchanged to transmit the necessary data.

In the present invention, the data type DataType is used for the association between data encoding and physical signal types, such as temperature, frequency, and switching value acquisition, etc.; the data written in the device or the data format read out using the combined command is corrected by communication Specify; in the communication correction mode, use the correction command (used for data storage format correction inside the device-related data command) to perform configuration correction on the corresponding data structure.

The communication correction command includes global parameters and single-item parameters. In the 16-bit word address, the global parameter generally occupies a 1-bit word address, and the single-item parameter generally occupies a 15-bit word address. Global parameters are used to define the function and type of the combined command, including channel selection, Read/Write data mapping selection, and setting of the number of data types. Single-item parameters are used to define single-item configuration parameters, including data type, starting channel and data length. Table 2 is the communication correction command parameter table, and the combination command parameter table is shown in Table 2.

Table 2

When configuring global parameters, the first step is to configure the channel of the combined command, set the channel selection bit in the global parameter to 0, and the configured combined command is stored in the combined command packet 0; set the channel selection bit to 1 , and the combined command after configuration is stored in the combined command data packet 1. After the combination instruction 0 and combination instruction 1 are configured, they can be called directly during application without additional configuration. The second step is to configure the length of the special broadcast data. When the special broadcast packet of the combined command is enabled, the different fields of the special broadcast packet are used as data for different devices (see the special broadcast packet section for details). The third step is to configure the Read/Write data mapping selection bit. By configuring this bit, the combined command enters the Read (read) or Write (write) state. In the read state, the master device sends a combination command to the slave device and then reads the slave device data; in the write state, the master device sends the combination command to the slave device and then writes data to the slave device. The fourth step is to configure the number of data types. Assuming that the number of configured data types is n, there are n types of data combinations in the combination instruction. After configuring the complete global parameters, the first n single parameters need to be configured.

For the configuration of each single parameter, the first step is to configure the data type; Table 3 is the corresponding table of data encoding and physical signal type, as shown in Table 3 (this table is a specific application example, and the scope of patent protection is not limited to this).

The data type adopts 6-bit encoding. When the communication system is insufficient to provide 6-bit encoding, the indirect reference to the data type can make the encoding compact and improve the communication efficiency. For devices that use "data type" indirectly, an index table is established inside the device. Each item of the index table corresponds to one data type in the table, and only corresponds to one data type, and the data types corresponding to each index are not repeated. . The master device can read the corresponding relationship between the index inside the device and the table. The index table is arranged according to the definition in the DataType table in ascending order of coding values.

table 3

The second step of single parameter configuration is to configure the starting data channel of the data. After setting the starting data channel, the third step of single parameter configuration is to configure the number of data channels. Assuming that there are n single-item parameters to be configured, configure each single-item parameter in turn, and the data format after the configuration can be saved directly, and can be directly retrieved during application.

Step 303 : Determine whether the special broadcast function bit in the configured combined instruction allows the special broadcast function of the configured combined instruction, if yes, go to step 304 , if not, go to step 305 .

Step 304: Perform bidirectional data transmission according to the special broadcast function; the special broadcast function is used for receiving a response packet in a combined command after the configuration and continuously responding.

The step 304 specifically includes: when the command received by the device is a sending data command and the device address is a broadcast address, correcting the special broadcast in the command according to the configured data channel, data length and the storage format of the command. The data length determines the current device data; the data length is an integer multiple of the length of the special broadcast data; the device is a master device or a slave device; when the RxTx function in the special mode command is enabled, the current device is transmitted The Rx response packet is used to continuously respond to the data; the Rx response packet contains the configured combined instruction to read the data; Rx is for reception, and Tx is for transmission.

The special broadcast packet function in the present invention is realized based on the combined instruction:

The special broadcast function bit of CmdMode can enable the special broadcast function of the combined command. When the command received by the device is a send data command, and the device address is the broadcast address, according to the command data channel Chnl, data length Len and DaComAdj (device The data required by the current device is determined by the length of the special broadcast data in the relevant data command (data storage format correction) command.

In the data received in this mode, the data channel Chnl of the command specifies the device address corresponding to the first group of data, and the subsequent data corresponds to the data corresponding to the device address of Chnl+1, Chnl+2..., and all data are stored continuously. Therefore, when this function is enabled, the special broadcast data length of all slave devices connected to the same bus must be the same. At this time, the allowable data length must be an integer multiple of the special broadcast data length, that is, data length=special broadcast data length×n, where n is the number of devices addressed by the broadcast packet.

Step 305: Use the bidirectional data transmission function of the configured combination instruction to perform bidirectional data transmission; the bidirectional data transmission function is used to send data and receive data simultaneously in one of the configured combination instructions.

The step 305 specifically includes: after the device is addressed and the device receives a Tx command, returning an Rx response packet.

The bidirectional data transmission function in the present invention is realized based on the combined instruction. Use the RxTx (Rx is receiving, Tx is sending) function in the combined instruction to realize the bidirectional transmission of data. When the device is selected and a Tx command is received, it will return an Rx response packet, which also contains the corresponding combined command to read data. In this case, the execution status of the Tx instruction is stored in the LastError (status of the last command execution) instruction. This instruction is usually used to monitor the running status of the Tx instruction when the RxTx mode is supported in the combined instruction. This parameter can be passed through SysPara1 command to get.

The RxTx function bit in the CmdMode (instruction special mode) instruction enables the RxTx function of the combined instruction. When the RxTx function is enabled, the Tx command in the combined command (if the command is valid and has enough valid data) is always responded with an Rx response packet, even if the execution of the TxData command is wrong.

In the above manner, data can be sent and obtained in a set of instructions at the same time, thereby improving the efficiency of communication; at the same time, when there is data to be sent, the isochronism of data collection will not be destroyed.

In the bidirectional data transmission process, when the transmission quantity is higher than the transmission quantity threshold, the isochronous transmission mode is used for bidirectional data transmission.

Figure 4 is a flow chart of data transmission in the isochronous transmission mode. As shown in Figure 4, the isochronous transmission is to improve the efficiency of communication when a large amount of data is collected. It is a supplement to the normal communication mode and is an optional mode. Isochronous communication always starts to calculate the time of a time slot from an isochronous packet, and the time between two isochronous packets is the period of isochronous transmission.

The total time of the isochronous transmission time slice cannot be greater than 70% of the entire isochronous transmission period, and only devices with a specific address can transmit data in a specific time slot. In a certain time slot x, only the device whose device address is x can initiate data transfer. The device transmits data in Rx response data packets, and the total time length from the start of data transmission to the end of data transmission cannot be greater than the total time length of the time slot (usually shorter than the time required to transmit two data bytes).

Due to the delay of bus transmission, the shortcoming of the RxTx function in the combined command is that the sending and receiving commands of multiple devices are not synchronized. The combination of the special broadcast packet function and the isochronous transmission function can realize the combined function of data reception and transmission, and can solve the RxTx function at the same time. The problem of asynchronous instructions in the middle. The advantage of the combined command RxTx function is its flexibility. It must be actively sent by the master device to receive and send data, while the combination of special broadcast packets and isochronous transmission functions have set time slots and can only be sent regularly. instruction. Therefore, the combined command RxTx function and the "isochronous transmission + special broadcast packet" function have complementary advantages and disadvantages, and each has its own value.

Figure 5 is a structural diagram of a digital communication transmission system between field devices provided by the present invention. As shown in Figure 5, a digital communication transmission system between field devices includes:

The device data combination instruction generation module 501 is used to generate the device data combination instruction by using the device instruction; the device instruction includes the device parameter setting instruction, the slave device operation mode, the last command execution status instruction, the device address instruction, and the special mode instruction. , store format correction instructions and combined data exchange instructions.

The configuration module 502 is configured to configure the device data combination instruction by using the communication correction instruction in the communication correction mode, and determine the configured combination instruction; the communication correction instruction includes a global parameter configuration instruction and a single parameter configuration instruction; The configured combined command is used to receive device data while sending device data.

The configuration module 502 specifically includes:

A global parameter configuration unit, configured to configure the global parameters in the device data combination instruction in the communication correction mode:

The first step: configure the channel of the device data combination command: when the global parameter channel selection bit is set to 0, the configured combination command is stored in the combination command packet 0; when the channel selection bit is set to 1 , the configured combined instruction is stored in combined instruction data packet 1;

The second step: configure the length of special broadcast data: after the special broadcast packet of the device data combination instruction is enabled, use different fields of the special broadcast packet as data of different devices;

Step 3: Configure the mapping selection bits for read data and write data: in the read state, the master device sends the configured combined command to the slave device and reads the slave device data; in the write state, the master device sends After the slave device sends the combined command that the configuration is completed, the master device data is written to the slave device;

Step 4: Configure the number of data types: Set the number of configured data types to n, then there are n data combinations in the combination instruction after the configuration is completed;

The single parameter configuration unit is used to configure the first n single parameters after the global parameters are configured:

Step 1: Configure the data type: The data type adopts 6-bit encoding. When the communication system is lower than the 6-bit encoding, the data type is configured by indirect reference data type;

Step 2: Configure the initial data channel of the data;

Step 3: Configure the number of data channels;

When the single parameter configuration is completed, the configured combined command is determined.

The first judgment module 503 is configured to judge whether the special broadcast function bit in the configured combination instruction allows the special broadcast function of the configured combination instruction, and obtain a first judgment result.

The special broadcast packet transmission module 504 is configured to, if the first judgment result indicates that the special broadcast function bit in the configured combination command allows the special broadcast function of the configured combination command, according to the special broadcast function Two-way data transmission is performed; the special broadcast function is used to receive a response packet in one of the configured combined instructions and continue to respond.

The special broadcast packet transmission module 504 specifically includes: a current device data determination unit, used for when the command received by the device is a send data command and the device address is a broadcast address, according to the configured data channel of the combined instruction, The data length and the length of the special broadcast data in the storage format correction instruction determine the current device data; the data length is an integer multiple of the length of the special broadcast data; the device is a master device or a slave device; the special broadcast packet transmission unit, with After the RxTx function in the special mode command is enabled, the current device data is transmitted and the Rx response packet is used to continuously respond; the Rx response packet contains the configured combination command for reading data; Rx For reception, Tx for transmission.

The bidirectional data transmission module 505 is configured to, if the first judgment result indicates that the special broadcast function bit in the configured combined command does not allow the special broadcast function of the configured combined command, use the configured special broadcast function. The bidirectional data transmission function of the combined instruction performs bidirectional data transmission; the bidirectional data transmission function is used to send data and receive data simultaneously in one of the configured combined instructions.

The two-way data transmission module 505 specifically includes: a two-way data transmission unit, configured to return an Rx response packet when the device is addressed and the device receives a Tx command.

In the bidirectional data transmission process, when the transmission quantity is higher than the transmission quantity threshold, the isochronous transmission mode is used for bidirectional data transmission.

The application of isochronous transmission technology can improve the efficiency of communication when there is a lot of collected data.

The combination of the isochronous transmission technology and the special broadcast packet transmission technology can also realize the bidirectional transmission of data, and at the same time, it can solve the problem that the combined command TxRx received by the device is not synchronized in the bidirectional data transmission technology. Therefore, the isochronous transmission + special broadcast packet transmission technology can not only realize the function of collecting data while sending data for the same command, but also improve the communication bandwidth utilization and ensure the synchronization of each device receiving the command.

The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant part can be referred to the description of the method.

The principles and implementations of the present invention are described herein using specific examples. The descriptions of the above embodiments are only used to help understand the method and the core idea of the present invention; meanwhile, for those skilled in the art, according to the present invention There will be changes in the specific implementation and application scope. In conclusion, the contents of this specification should not be construed as limiting the present invention.

Claims (8)

1. A method for transmitting digital communications between field devices, comprising:

generating a device data combination instruction by using the device instruction; the device instruction comprises a device parameter setting instruction, a slave device operation mode, a last command execution state instruction, a device address instruction, a special mode instruction, a storage format correction instruction and a combined data exchange instruction;

in a communication correction mode, configuring the equipment data combination instruction by using a communication correction instruction, and determining the configured combination instruction; the communication correction instruction comprises a global parameter configuration instruction and a single parameter configuration instruction; the configured combination instruction is used for receiving the device data while sending the device data;

judging whether the special broadcast function position in the configured combined instruction allows the special broadcast function of the configured combined instruction or not to obtain a first judgment result;

if the first judgment result shows that the special broadcast function position in the configured combined instruction allows the special broadcast function of the configured combined instruction, performing bidirectional data transmission according to the special broadcast function; the special broadcast function is used for receiving a response packet in a configured combined instruction and continuously responding; the special broadcasting function is that the master equipment sends data packets or instructions to the slave equipment, the slave equipment receives the same data packets or instructions, and each slave equipment finds the corresponding data packets or instructions from the received data packets or instructions and carries out corresponding response; the bidirectional data transmission according to the special broadcasting function specifically includes:

when the command received by the equipment is a data sending command and the equipment address is a broadcast address, determining the current equipment data according to the data channel and the data length of the configured combined instruction and the special broadcast data length in the storage format correction instruction; the data length is integral multiple of the special broadcast data length; the equipment is master equipment or slave equipment;

transmitting the current device data and continuously responding by using an Rx response packet after an RxTx function in the special mode instruction is enabled; the Rx reply packet comprises the configured combination instruction of the read data; rx is receiving and Tx is transmitting;

if the first judgment result indicates that the special broadcast function position in the configured combined instruction does not allow the special broadcast function of the configured combined instruction, performing bidirectional data transmission by using the bidirectional data transmission function of the configured combined instruction; the bidirectional data transmission function is used for simultaneously sending data and receiving data in one configured combined instruction.

2. The method according to claim 1, wherein in the communication calibration mode, the device data combination command is configured by using the communication calibration command, and the determining of the configured combination command specifically includes:

in a communication correction mode, configuring global parameters in the device data combination instruction:

the first step is as follows: configuring a channel of the equipment data combination instruction: when the global parameter channel selection bit is set to 0, the configured combination instruction is stored in a combination instruction data packet 0; when the channel selection bit is set to 1, the configured combined instruction is stored in a combined instruction data packet 1;

the second step is that: configuring the length of special broadcast data: when the special broadcast packet of the equipment data combination instruction is enabled, taking different fields of the special broadcast packet as data of different equipment;

the third step: configuring mapping selection bits of read data and write data: in a reading state, the master device sends a configured combination instruction to the slave device and then reads the data of the slave device; in a writing state, after sending a configured combination instruction to the slave equipment, the master equipment writes the data of the master equipment into the slave equipment;

the fourth step: number of configuration data types: setting the number of the configured data types as n, and then combining n data combinations in the combined instruction after configuration is finished;

after the global parameters are configured, configuring the first n single parameters:

the first step is as follows: the type of configuration data: the data type adopts 6-bit coding, and when the communication system is lower than the 6-bit coding, the data type is configured in an indirect data type reference mode;

the second step is that: configuring a starting data channel of data;

the third step: configuring the number of data channels;

and when the configuration of the single parameter is finished, determining the configured combined instruction.

3. The method according to claim 1, wherein the bidirectional data transmission using the configured bidirectional data transmission function of the combination command includes:

when a device is addressed and the device receives a Tx command, it returns an Rx acknowledgement packet.

4. The method of any one of claims 1-3, wherein during the bi-directional data transmission, when the transmission amount is above the transmission amount threshold, bi-directional data transmission is performed using an isochronous transmission mode.

5. A system for transmitting digital communications between field devices, comprising:

the equipment data combination instruction generation module is used for generating an equipment data combination instruction by using the equipment instruction; the device instruction comprises a device parameter setting instruction, a slave device operation mode, a last command execution state instruction, a device address instruction, a special mode instruction, a storage format correction instruction and a combined data exchange instruction;

the configuration module is used for configuring the equipment data combination instruction by using the communication correction instruction in the communication correction mode and determining the configured combination instruction; the communication correction instruction comprises a global parameter configuration instruction and a single parameter configuration instruction; the configured combination instruction is used for receiving the device data while sending the device data;

the first judging module is used for judging whether the special broadcasting function position in the configured combined instruction allows the special broadcasting function of the configured combined instruction or not to obtain a first judging result;

a special broadcast packet transmission module, configured to perform bidirectional data transmission according to the special broadcast function if the first determination result indicates that the special broadcast function position in the configured combination instruction allows the special broadcast function of the configured combination instruction; the special broadcast function is used for receiving a response packet in a configured combined instruction and continuously responding; the special broadcasting function is that the master equipment sends data packets or instructions to the slave equipment, the slave equipment receives the same data packets or instructions, and each slave equipment finds the corresponding data packets or instructions from the received data packets or instructions and carries out corresponding response; the bidirectional data transmission according to the special broadcasting function specifically includes:

when the command received by the equipment is a data sending command and the equipment address is a broadcast address, determining the current equipment data according to the data channel and the data length of the configured combined instruction and the special broadcast data length in the storage format correction instruction; the data length is integral multiple of the special broadcast data length; the equipment is master equipment or slave equipment;

transmitting the current device data and continuously responding by using an Rx response packet after an RxTx function in the special mode instruction is enabled; the Rx reply packet comprises the configured combination instruction of the read data; rx is receiving and Tx is transmitting;

a bidirectional data transmission module, configured to perform bidirectional data transmission by using a bidirectional data transmission function of the configured combination instruction if the first determination result indicates that the special broadcast function position in the configured combination instruction does not allow the special broadcast function of the configured combination instruction; the bidirectional data transmission function is used for simultaneously sending data and receiving data in one configured combined instruction.

6. The system of claim 5, wherein the configuration module comprises:

a global parameter configuration unit, configured to configure, in the communication correction mode, a global parameter in the device data combination instruction:

the first step is as follows: configuring a channel of the equipment data combination instruction: when the global parameter channel selection bit is set to 0, the configured combination instruction is stored in a combination instruction data packet 0; when the channel selection bit is set to 1, the configured combined instruction is stored in a combined instruction data packet 1;

the second step is that: configuring the length of special broadcast data: when the special broadcast packet of the equipment data combination instruction is enabled, taking different fields of the special broadcast packet as data of different equipment;

the third step: configuring mapping selection bits of read data and write data: in a reading state, the master device sends a configured combination instruction to the slave device and then reads the data of the slave device; in a writing state, after sending a configured combination instruction to the slave equipment, the master equipment writes the data of the master equipment into the slave equipment;

the fourth step: number of configuration data types: setting the number of the configured data types as n, and then combining n data combinations in the combined instruction after configuration is finished;

and the single parameter configuration unit is used for configuring the first n single parameters after the global parameters are configured:

the first step is as follows: the type of configuration data: the data type adopts 6-bit coding, and when the communication system is lower than the 6-bit coding, the data type is configured in an indirect data type reference mode;

the second step is that: configuring a starting data channel of data;

the third step: configuring the number of data channels;

and when the configuration of the single parameter is finished, determining the configured combined instruction.

7. The system of claim 6, wherein the bidirectional data transmission module comprises:

and the bidirectional data transmission unit is used for returning an Rx response packet when the equipment receives a Tx command after the equipment is addressed.

8. The transmission system according to any one of claims 5 to 7, wherein during the bidirectional data transmission, when the transmission amount is above the transmission amount threshold, bidirectional data transmission is performed using an isochronous transmission mode.

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