CN112583676B

CN112583676B - Information transmission method

Info

Publication number: CN112583676B
Application number: CN201910925643.XA
Authority: CN
Inventors: 徐珺
Original assignee: Kyland Technology Co Ltd
Current assignee: Kyland Technology Co Ltd
Priority date: 2019-09-27
Filing date: 2019-09-27
Publication date: 2022-05-17
Anticipated expiration: 2039-09-27
Also published as: CN112583676A

Abstract

The embodiment of the invention discloses an information transmission method, which comprises the following steps: the node equipment selects a matched orthogonal frequency division multiplexing OFDM symbol to send an access application message according to a reserved resource message broadcast by the control equipment on the high-speed industrial control bus; when the access application message is legal, the control equipment sends an access response message to the node equipment; the node equipment determines a matched node identifier according to the access response message; the control equipment broadcasts an MAC unicast address message according to the node identification of each node equipment; the node equipment sends a dynamic bandwidth application message according to the node identifier; when the dynamic bandwidth application message is legal, the control equipment sends a dynamic bandwidth release message to the node equipment; the control equipment and the node equipment issue messages according to the dynamic bandwidth, and send the service data in the form of messages and/or fragment messages; the various messages transmitted on the bus follow the frame structure of the MAC layer. The embodiment of the invention can carry out communication through a unified frame structure of the MAC layer.

Description

Information transmission method

Technical Field

The embodiment of the invention relates to the field of industrial communication, in particular to an information transmission method.

Background

The two-wire network includes a control device, at least one node device, and a high-speed industrial control bus. The control equipment and the node equipment are connected through a high-speed industrial control bus to form a two-wire network and communicate with each other.

In order to ensure that each device in a two-wire network can understand the information transmitted by the other devices, it is necessary to define a frame format for communication between the devices on the two-wire network. There is a uniform frame format definition, which is equivalent to unifying the language of speech between devices. On a two-wire network, all devices communicate with each other using the same set of frame formats, enabling mutual understanding.

In the prior art, high-speed industrial control buses are all based on time domains, namely, control equipment and node equipment communicate according to a time sequence, data can not be sent by a plurality of pieces of equipment in a two-wire network at the same time, and the communication efficiency is low.

Disclosure of Invention

The invention provides an information transmission method, which is used for realizing the control equipment and the node equipment which are hung on a high-speed industrial control bus, and the communication is carried out through a uniform frame format, so that each equipment can understand the information transmitted by other equipment, the mutual understanding can be realized, a plurality of equipment can send data at the same time, and the communication efficiency is improved.

The embodiment of the invention provides an information transmission method, which is characterized by being applied to control equipment and node equipment hung on a high-speed industrial control bus, and comprising the following steps:

the control equipment broadcasts a reserved resource message on a high-speed industrial control bus;

the node equipment selects the matched orthogonal frequency division multiplexing OFDM symbol to send an access application message according to the information in the reserved resource message;

when verifying that the access application message is legal, the control equipment sends an access response message to the node equipment;

the node equipment determines a matched node identifier according to the access response message;

the control equipment broadcasts an MAC unicast address message according to the node identification of each node equipment on the high-speed industrial control bus;

the node equipment sends a dynamic bandwidth application message according to the node identifier;

when verifying that the dynamic bandwidth application message is legal, the control equipment sends a dynamic bandwidth release message to the node equipment;

the control equipment and the node equipment send respective service data on the high-speed industrial control bus in the form of messages and/or fragment messages according to the bandwidth allocation information in the dynamic bandwidth release messages;

various messages transmitted on the high-speed industrial control bus follow the frame structure of an MAC layer;

in the frame structure of the MAC layer, a first byte is used to define the information type, the whole of a second byte and a set bit position in a third byte to define the information length, the remaining bit positions in the third byte are used to define a status flag, and at least one byte from a fourth byte is used to define other information matching the information definition type.

According to the technical scheme of the embodiment of the invention, the reserved resource message is broadcasted on the high-speed industrial control bus through the control equipment; the node equipment selects the matched orthogonal frequency division multiplexing OFDM symbol to send an access application message according to the information in the reserved resource message; when verifying that the access application message is legal, the control equipment sends an access response message to the node equipment; the node equipment determines a matched node identifier according to the access response message; node identifiers of all node devices on a high-speed industrial control bus of the control device broadcast MAC unicast address messages; the node equipment sends a dynamic bandwidth application message according to the node identifier; when verifying that the dynamic bandwidth application message is legal, the control equipment sends a dynamic bandwidth release message to the node equipment; the control device and the node device issue bandwidth allocation information in a message according to dynamic bandwidth, and send respective service data on the high-speed industrial control bus in the form of messages and/or fragmented messages, wherein various messages transmitted on the high-speed industrial control bus follow the frame structure of an MAC layer, so that the control device and the node device hung on the high-speed industrial control bus can communicate through the frame structure of the uniform MAC layer, and the devices can understand information transmitted by other devices and can understand each other, and can transmit information through the frame structure of the MAC layer, thereby realizing dynamic addition of the node device, dynamic allocation of the node device resources and service data communication, and realizing information transmission by using OFDM technology, thereby realizing that the high-speed industrial control bus is based on a mode of combining time domain and frequency domain, and the control device and the node device hung on the high-speed industrial control bus can be different according to frequency, and data are sent at the same time, so that the communication efficiency is improved.

Drawings

Fig. 1 is a flowchart of an information transmission method according to an embodiment of the present invention;

fig. 2 is a flowchart of an information transmission method according to a second embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention.

It should be further noted that, for the convenience of description, only some but not all of the relevant aspects of the present invention are shown in the drawings. Before discussing exemplary embodiments in more detail, it should be noted that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although a flowchart may describe the operations (or steps) as a sequential process, many of the operations can be performed in parallel, concurrently or simultaneously. In addition, the order of the operations may be re-arranged. The process may be terminated when its operations are completed, but may have additional steps not included in the figure. The processes may correspond to methods, functions, procedures, subroutines, and the like.

Example one

Fig. 1 is a flowchart of an information transmission method according to an embodiment of the present invention. The embodiment is applied to the control equipment and the node equipment which are hung on the high-speed industrial control bus, and can be applied to the condition that the control equipment and the node equipment which are hung on the high-speed industrial control bus are communicated with each other.

As shown in fig. 1, the method of this embodiment specifically includes:

step 101, the control device broadcasts a reserved resource message on a high-speed industrial control bus.

Various messages transmitted on the high-speed industrial control bus follow the frame structure of an MAC layer; in the frame structure of the MAC layer, a first byte is used to define the information type, the whole of a second byte and a set bit position in a third byte to define the information length, the remaining bit positions in the third byte are used to define a status flag, and at least one byte from a fourth byte is used to define other information matching the information definition type.

The frame structure of the MAC layer provided by the embodiment of the invention is a frame format used for communication between control equipment and node equipment which are hung on a high-speed industrial control bus. The control equipment and the node equipment hung on the high-speed industrial control bus form a two-wire network. The two-wire network includes a control device and at least one node device. The control device is responsible for the configuration and management of the entire two-wire network and also for bandwidth allocation for communications between node devices. The node equipment uses the allocated bandwidth resources to exchange information to complete a specific control task. All devices in the two-wire network use the frame structure of the MAC layer to communicate with each other, so that each device can understand information transmitted by other devices, and mutual understanding can be achieved. Some frame formats are used for system management purposes to control node device access, bandwidth resource allocation, etc. Some frame formats are used for data communication between the machines and electronics, conveying the values of various industrial control semaphores.

The frame structure of the MAC layer provided by the embodiment of the invention is a universal frame format. The generic frame format is the base definition. In all frame formats, the first byte is used to define the information type, the whole of the second byte and the set bit position in the third byte is used to define the information length. I.e., all frame formats must have an information Type (Type) field and an information Length (Length) field. For all messages delivered, the first byte must be a Type field. The setting range of Type is 0-255. Wherein, the range 0-31 is reserved for the MAC layer for system management, the range 32-191 is allocated to specific industry scene definition, and the remaining range 192-255 is allocated to user-defined use.

Optionally, in the frame structure of the MAC layer, all of the second byte and the first two bit positions of the third byte are used to define the information length, and the remaining six bit positions of the third byte are used to define the status flag.

The definition of the general frame format is shown in table 1. Byte Offset is the Byte position. Bit Offset is a Bit position. The Type field is 8bits, occupying byte 0 (the first byte). The Length field is 10 bits, occupying 8bits of byte 1 (second byte) and 2 bits of byte 2 (third byte). In other frame format definitions, the remaining 6 bits in byte 2 (the third byte) may be used to define various status flag (Flags) fields. Bytes (total Length-3 bytes) following byte 3 (fourth byte) belong to the information record (Payload) section for defining other information matching the information definition type.

Table 1 general frame format

Alternatively, the two-wire network may be a fixed network. The control equipment and the node equipment hung on the high-speed industrial control bus are nodes in the two-wire network. In a fixed network, the number of nodes is fixed, the logical addresses (such as MAC and IP addresses) are fixed, the physical positions on the bus are fixed, and the nodes are not allowed to be added or deleted randomly in the operation process.

Alternatively, the two-wire network may be a dynamic network. In the dynamic network, the number of nodes is indefinite, the address is indefinite, and the nodes are allowed to join and leave in the running process.

Each node will have a node identity (NodeId). Optionally, the control device fixedly uses a node identifier 0, 255 denotes a broadcast node identifier, and 254 denotes an uncertain node identifier. The [2, x ] range is the unicast node identification range used by the node device and [ y,253] is the multicast node identification range, the two ranges cannot overlap, so 2< x < y <253 is required.

The minimum time slice unit in the two-wire network is a time slot (TimeSlot), and 64 timeslots form one Frame (Frame). And 256 frames constitute one Super-Frame (Super-Frame).

Optionally, when the reserved resource packet is broadcast through a frame structure of the MAC layer, the state identifier is a reserved field; in the frame structure of the MAC layer, a fourth byte is used for defining the serial number of reserved resources used in a network currently configured by the high-speed industrial control bus; in the frame structure of the MAC layer, the fifth byte is used to define the number of reserved resources that are available in the current network; a sixth byte, configured to define an offset of the reserved resource in the current information in the reserved resource allocation table; a seventh byte for defining the number of reserved resources in the current information; in the frame structure of the MAC layer, starting from the eighth byte, taking six bytes as a unit, and respectively defining a reserved resource allocation table entry under each unit; in each reserved resource allocation table entry, a first byte is used for defining a node identifier of a source node of a reserved resource, a second byte is used for defining a node identifier of a destination node of the reserved resource, a third byte is used for defining a resource type of the reserved resource, the first six bit positions in a fourth byte are used for defining the number of time slots of the reserved resource, the last two bit positions of the fourth byte are used for defining acknowledgement information that the reserved resource only uses an upper sideband, only uses a lower sideband or uses all sidebands, all of the fifth byte and the first bit position of the sixth byte are used for defining the time slot position of the reserved resource, the second bit position to the fifth bit position of the sixth byte are reserved fields, and the last three bit positions of the sixth byte are used for defining the cycle period of the reserved resource.

The definition form of the frame structure of the MAC layer for broadcasting the reserved resource packet is shown in table 2. The field meanings in the frame structure of the MAC layer for broadcasting the reserved resource packet are shown in table 3.

Table 2 frame structure of MAC layer for broadcasting reserved resource packet

Table 3 field significance in frame structure of MAC layer for broadcasting reserved resource messages

And the control equipment broadcasts a reserved resource message on the high-speed industrial control bus. The information contained in the reserved resource message is reserved resource information. As shown in tables 2 and 3, the information type of the reserved resource packet is 5, and the state identifier is a reserved field (Rsvd); in the frame structure of the MAC layer, a fourth byte is used for defining the serial number (FixRes _ SN) of the reserved resource used in the network currently configured by the high-speed industrial control bus; in the frame structure of the MAC layer, a fifth byte, which is used to define the number of reserved resources (Total _ Active _ Num) that are available in the current network; a sixth byte for defining an Offset (Cur _ Offset) of the reserved resources in the current information in the reserved resource allocation table; a seventh byte for defining the number of reserved resources (Cur _ Num) in the current information; in the frame structure of the MAC layer, starting from the eighth byte, taking six bytes as a unit, and respectively defining a reserved resource allocation table entry under each unit; in each reserved resource allocation table entry, a first byte is used to define a Node identifier (Src-Node) of a source Node of the reserved resource, a second byte is used to define a Node identifier (Dst-Node) of a destination Node of the reserved resource, a third byte is used to define a resource Type (Type _ ID) of the reserved resource, a first six bit positions in a fourth byte is used to define a number of slots (Len) of the reserved resource, a last two bit positions of the fourth byte is used to define acknowledgement information (Band) that the reserved resource uses only an upper sideband, only a lower sideband or all sidebands, all of a fifth byte and a first bit position of a sixth byte is used to define a slot position (Pos) of the reserved resource, a second bit position to a fifth bit position of the sixth byte are a reserved field (Rsvd), a last three bit positions of the sixth byte, for defining a cycle period (Freq) for reserving resources.

And 102, the node equipment selects the matched orthogonal frequency division multiplexing OFDM symbol to send an access application message according to the information in the reserved resource message.

After the node equipment is powered on, the node equipment receives the broadcasted reserved resource message, and selects the matched orthogonal frequency division multiplexing OFDM symbol to send the access application message according to the information in the reserved resource message.

Optionally, when the access application packet is transmitted through the frame structure of the MAC layer, the status flag is a reserved field;

in the frame structure of the MAC layer, the fourth byte is used to define a node identifier of a node device that issues an access application; in a frame structure of an MAC layer, the first four bit positions of a fifth byte are used to define a current operating state of a node device, the fifth bit position of the fifth byte is used to define whether the node device receives acknowledgement information of a complete fixed resource allocation table, the sixth bit position of the fifth byte is used to define whether the node device receives acknowledgement information of a complete multicast table, and the last two bit positions of the fifth byte are reserved fields; in a frame structure of the MAC layer, a sixth byte is used to define the number of other node devices that the node device can monitor, and a seventh byte is used to define, at a fifth bit position of the fifth byte, a sequence number of a latest fixed resource received by the node device when an acknowledgement message of a complete fixed resource allocation table is received; in the frame structure of the MAC layer, an eighth byte is used to define a device type of the node device, and all bit positions of the ninth byte through the twelfth byte are used to define a MAC address of the node device.

The frame structure of the MAC layer for transmitting the access application packet is a frame structure used when the node device reports its own state to the control device. The definition form of the frame structure of the MAC layer for transmitting the access application message is shown in table 4. The field meanings in the frame structure of the MAC layer for transmitting the access application message are shown in table 5.

Table 4 frame structure of MAC layer for transmitting access application packet

Table 5 field significance in the frame structure of the MAC layer for sending access application messages

As shown in tables 4 and 5, the information type of the access application packet is 6; when the access application message is transmitted through the frame structure of the MAC layer, the state mark is a reserved field (Rsvd); a fourth byte, which is used for defining a Node identifier (Src _ Node) of the Node device sending the access application; the first four bit positions of the fifth byte are used for defining the current running State (State) of the node device, the fifth bit position of the fifth byte is used for defining whether the node device receives the acknowledgement information (FixRes) of the complete fixed resource allocation table, the sixth bit position of the fifth byte is used for defining whether the node device receives the acknowledgement information (Group) of the complete multicast table, and the last two bit positions of the fifth byte are reserved fields (Rsvd); a sixth byte for defining the number (Access _ Cnt) of other node devices that the node device can monitor, and a seventh byte for defining a serial number (FixRes _ Version) of the latest fixed resource received by the node device when the fifth bit position of the fifth byte defines that the acknowledgement information of the complete fixed resource allocation table is received; in the frame structure of the MAC layer, an eighth byte is used to define a Device Type (Device _ Type) of the node Device, and all bit positions of the ninth byte through the twelfth byte are used to define a MAC Address (MAC) of the node Device.

Step 103, when verifying that the access application message is legal, the control device sends an access response message to the node device.

When verifying that an access application message sent by the node equipment is legal, the control equipment sends an access response message to the node equipment; and when verifying that the access application message sent by the node equipment is illegal, the control equipment ignores the access application message.

Optionally, when the access response packet is transmitted through the frame structure of the MAC layer, the status flag is a reserved field; in the frame structure of the MAC layer, the fourth byte is used to define a node identifier allocated to a node device that sends an access application; a fifth byte for defining an action type of the access response; all bit positions of the sixth byte to the eleventh byte are used for defining a medium access control address of the node device.

The frame structure of the MAC layer for transmitting the access response packet is a frame structure used when the control device responds to the access application of the node device and allocates a node identifier and other states to the node device. A frame structure of the MAC layer for transmitting the access response message is defined as shown in table 6. The meaning of the fields in the frame structure of the MAC layer for transmitting the access response message is shown in table 7.

Table 6 frame structure of MAC layer for transmitting access response packet

Table 7 field meanings in the frame structure of the MAC layer for transmitting access response messages

As shown in table 6 and table 7, the information type of the access response packet is 7; when the access response message is transmitted through the frame structure of the MAC layer, the state mark is a reserved field (Rsvd); a fourth byte, which is used for defining a Node identifier (Dst _ Node) distributed for the Node equipment sending the access application; a fifth byte, which is used for defining the Action type (Action) of the access response; all bit positions of the sixth byte through the eleventh byte define a media access control address (MAC) of the node device.

And step 104, the node equipment determines the matched node identification according to the access response message.

The access response message includes a node identifier allocated to the node device by the control device.

And 105, broadcasting the MAC unicast address message by the control equipment according to the node identification of each node equipment on the high-speed industrial control bus.

Optionally, when the MAC unicast address distribution packet is transmitted through a frame structure of the MAC layer, the status flag is a reserved field; in a frame structure of the MAC layer, a fourth byte is used to define the number of operations matching the adding or deleting operations of the node devices in the network, and a fifth byte is used to define the number of node devices in a running state in the current network; in the frame structure of the MAC layer, a sixth byte is used to define an offset of the MAC table in the current information in the complete MAC table; a seventh byte for defining the number of MAC table entries included in the current information; in the frame structure of the MAC layer, starting from the eighth byte, seven bytes are taken as a unit, and MAC table entries are respectively defined under each unit; in the MAC entry, the first byte is the node identifier of the node device, and the last six bytes are the MAC address of the node device.

The frame structure of the MAC layer for transmitting the MAC unicast address distribution packet indicates the correspondence between the node identifiers and the MAC addresses of all nodes in the two-wire network. The definition form of the frame structure of the MAC layer for transmitting the MAC unicast address distribution packet is shown in table 8. The field meanings in the frame structure of the MAC layer for transmitting the MAC unicast address distribution packet are shown in table 9.

Table 8 frame structure of MAC layer for transmitting MAC unicast address distribution packet

Table 9 field meanings in the frame structure of the MAC layer for transmitting MAC unicast address distribution messages

Field(s)	Of significance
		Type	3
MACTbl_SN	Number of operations matching addition or deletion operations of node devices in network
		Total_Active_Nodes	Number of node devices currently in operation in network
Cur_Offset	Current letterOffset of MAC table in full MAC table
		Cur_Num	The number of MAC table entries included in the current information

As shown in tables 8 and 9, the information type of the MAC unicast address distribution packet is 3; when the MAC unicast address issuing message is transmitted through a frame structure of an MAC layer, the state mark is a reserved field (Rsvd); a fourth byte for defining the number of operations (MacTbl _ SN) matching the adding or deleting operations of the node devices in the network, and a fifth byte for defining the number of node devices (Total _ Active _ Nodes) in a running state in the current network; a sixth byte for defining an Offset (Cur _ Offset) of the MAC table in the current information in the full MAC table; a seventh byte for defining the number of MAC entries (Cur _ Num) included in the current information; in the frame structure of the MAC layer, starting from the eighth byte, seven bytes are taken as a unit, and MAC table entries are respectively defined under each unit; in the MAC entry, the first byte is a node identifier (NodeId) of the node device, and the last six bytes are an MAC address of the node device.

And 106, the node equipment sends a dynamic bandwidth application message according to the node identifier.

Optionally, when the dynamic bandwidth application message is transmitted through the frame structure of the MAC layer, the status flag is a reserved field; in the frame structure of the MAC layer, the fourth byte is used for defining the node identification of the source node applying for the dynamic bandwidth; a fifth byte, which is used for defining the node identification of the destination node applying for the dynamic bandwidth; a sixth byte, which is used for defining the service type of the application dynamic bandwidth; a seventh byte, configured to define the number of time slots for applying for the dynamic bandwidth; the first three bit positions of the eighth byte are used for defining the real-time priority of applying for the dynamic bandwidth, and the last five bit positions of the eighth byte are reserved fields.

The definition of the frame structure of the MAC layer for transmitting the dynamic bandwidth application message is shown in table 10. The field meanings in the frame structure of the MAC layer for transmitting the dynamic bandwidth application message are shown in table 11.

Table 10 frame structure of MAC layer for transmitting dynamic bandwidth application message

Table 11 field meanings in the frame structure of the MAC layer for transmitting dynamic bandwidth application messages

Field(s)	Of significance
		Type	8
Src_Node	Node identification of source node applying for dynamic bandwidth
		Dst_Node	Node identification of destination node applying for dynamic bandwidth
TypeId	Type of service applying for dynamic bandwidth
		Symbs	Number of time slots for dynamic bandwidth application
Real	Applying real-time priority of dynamic bandwidth

As shown in table 10 and table 11, the information type of the dynamic bandwidth application packet is 8; when the dynamic bandwidth application message is transmitted through the frame structure of the MAC layer, the state mark is a reserved field (Rsvd); in the frame structure of the MAC layer, the fourth byte is used to define a Node identifier (Src _ Node) of a source Node applying for a dynamic bandwidth; a fifth byte, which is used for defining a Node identifier (Dst _ Node) of a destination Node applying for the dynamic bandwidth; a sixth byte for defining a type of service (TypeId) for applying for dynamic bandwidth; a seventh byte for defining the number of slots for which dynamic bandwidth is applied (Symbs); the first three bit positions of the eighth byte are used to define the Real-time priority (Real) of the application for dynamic bandwidth, and the last five bit positions of the eighth byte are reserved field (Rsvd).

And step 107, when the control device verifies that the dynamic bandwidth application message is legal, sending a dynamic bandwidth issue message to the node device.

When verifying that the dynamic bandwidth application message sent by the node equipment is legal, the control equipment sends a dynamic bandwidth release message to the node equipment; and when verifying that the dynamic bandwidth application message sent by the node equipment is illegal, the control equipment ignores the dynamic bandwidth application message.

Optionally, when the dynamic bandwidth distribution message is transmitted through the frame structure of the MAC layer, the status flag is a reserved field; in a frame structure of the MAC layer, a fourth byte for defining the number of dynamic resources included in the information; in the frame structure of the MAC layer, starting from the fifth byte, taking the five bytes as a unit, and respectively defining the description information of each dynamic resource under each unit; in the description information of the dynamic resource, a first byte is used for defining a node identification of a source node of the dynamic resource, a second byte is used for defining a node identification of a destination node of the dynamic resource, a third byte is used for defining a service type of the dynamic resource, the first six bit positions of a fourth byte are used for defining a time slot length of the dynamic resource, the last two bit positions of the fourth byte are used for defining acknowledgement information of the dynamic resource using only an upper sideband, only a lower sideband or all sidebands, the first six bit positions of a fifth byte are used for defining a time slot position of the dynamic resource, and the last two bit positions of the fifth byte are reserved fields.

The definition of the frame structure of the MAC layer for transmitting the dynamic bandwidth allocation message is shown in table 12. The field meanings in the frame structure of the MAC layer for transmitting the dynamic bandwidth allocation message are shown in table 13.

Table 12 frame structure of MAC layer for transmitting dynamic bandwidth distribution packet

Table 13 field meanings in the frame structure of the MAC layer for transmitting dynamic bandwidth allocation messages

As shown in table 12 and table 13, the information type of the dynamic bandwidth allocation packet is 9; when the dynamic bandwidth issuing message is transmitted through the frame structure of the MAC layer, the state mark is a reserved field (Rsvd); a fourth byte for defining the number of dynamic resources (Dyn _ Num) included in the information in a frame structure of the MAC layer; in the frame structure of the MAC layer, starting from the fifth byte, taking the five bytes as a unit, and respectively defining the description information of each dynamic resource under each unit; in the description information of the dynamic resource, a first byte is used to define a Node identification (Src _ Node) of a source Node of the dynamic resource, a second byte is used to define a Node identification (Dst _ Node) of a destination Node of the dynamic resource, a third byte is used to define a traffic type (TypeId) of the dynamic resource, a first six bit positions of a fourth byte is used to define a slot length (Len) of the dynamic resource, a last two bit positions of the fourth byte is used to define acknowledgement information (Band) that the dynamic resource uses only an upper sideband, only a lower sideband or all sidebands, a first six bit positions of a fifth byte is used to define a slot position (Pos) of the dynamic resource, and a last two bit positions of the fifth byte is a reserved field (Rsvd).

And step 108, the control equipment and the node equipment send respective service data in the form of messages and/or fragment messages on the high-speed industrial control bus according to the bandwidth allocation information in the dynamic bandwidth release messages.

The control device and the node device send respective service data according to the bandwidth allocation information in the dynamic bandwidth release message. If the number of the service data does not exceed the minimum sideband bytes, sending the respective service data on the high-speed industrial control bus in a message form; and if the service data exceeds the minimum sideband byte number, transmitting the respective service data on the high-speed industrial control bus in a form of a fragment message.

Optionally, when the service data in the form of the fragment message is transmitted through the frame structure of the MAC layer, the status flag is fragment information; in the frame structure of the MAC layer, a fourth byte is used to define the node identification of the source node, a fifth byte is used to define the node identification of the destination node, and starting from the sixth byte, the information payload is defined.

Optionally, in the status flag, the first bit position and the second bit position are used to define a relationship between the current data packet and the complete ethernet packet; the last three bit positions are used for defining the counting result of the message fragment corresponding to the current data packet; when the first bit position is 1 and the second bit position is 1, the method is used for defining the current data packet as a separately encapsulated complete Ethernet message; when the first bit position is 1 and the second bit position is 0, the method is used for defining the current data packet as the initial part of the Ethernet message fragment; when the first bit position is 0 and the second bit position is 1, the method is used for defining the current data packet as the end part of the Ethernet message fragment; and when the first bit position is 0 and the second bit position is 0, defining the current data packet as the middle part of the Ethernet message fragment.

A defined form of a frame structure of the MAC layer for transmitting service data in the form of a fragmented packet is shown in table 14.

Table 14 frame structure of MAC layer for transmitting service data in the form of fragmented packets

As shown in table 14, when transmitting service data in the form of a fragment packet through a frame structure of the MAC layer, the status flag is fragment information (SN, EOF, and SOF); in the frame structure of the MAC layer, a fourth byte is used to define a Node identifier (Src _ Node) of a source Node, a fifth byte is used to define a Node identifier (Dst _ Node) of a destination Node, and starting from the sixth byte, an information Payload (Payload) is defined. In the state flag, SOF and EOF are used to define the relation between the current data packet and the complete Ethernet message; and the SN is used for defining the counting result of the message fragments corresponding to the current data packet. The definition of the meaning of SOF and EOF is shown in Table 15.

TABLE 15 definition of the meanings of SOF and EOF

SOF	EOF	Description of the invention
			1	1	The current data packet is a complete Ethernet message packaged independently
1	0	The current data packet is the initial part of the Ethernet message fragment
			0	1	The current data packet is the end part of the Ethernet message fragment
0	0	The current data packet is the middle part of the Ethernet message fragment

As shown in table 15, when SOF is 1 and EOF is 1, the method is used to define the current data packet as a separately encapsulated complete ethernet packet; when the SOF is 1 and the EOF is 0, the method is used for defining the current data packet as the initial part of the Ethernet message fragment; when the SOF is 0 and the EOF is 1, the method is used for defining the current data packet as the end part of the Ethernet message fragment; and when the SOF is 0 and the EOF is 0, defining the current data packet as the middle part of the Ethernet message fragment.

Optionally, the information transmission method may further include: the control equipment broadcasts a network control word message at the initial position of each frame; when the network control word message is transmitted through the frame structure of the MAC layer, the state mark is the system software version number of the high-speed industrial control bus; in the frame structure of the MAC layer, a fourth byte is used for defining the sequence number of a fixed resource used in a network currently configured by the high-speed industrial control bus; in the frame structure of the MAC layer, the first six bit positions of the fifth byte are used for defining network coding parameters, and the last two bit positions of the fifth byte are used for defining the transmitting power proportion of the upper and lower sidebands of an OFDM symbol; in the frame structure of the MAC layer, the first two bit positions of the sixth byte are used to define the acknowledgement information whether the upper sideband of the OFDM symbol uses continuous pilots, and the last six bit positions of the sixth byte are reserved fields; in a frame structure of a MAC layer, a first bit position of a seventh byte is used for defining the information transmitted only by using a lower sideband of an OFDM symbol or the confirmation information transmitted by using the whole sideband of the OFDM symbol, a second bit position of the seventh byte is used for defining the current network state, a third bit position of the seventh byte is used for defining the confirmation information uniformly scheduled by an upper sideband and a lower sideband of the OFDM symbol or independently scheduled by the upper sideband and the lower sideband of the OFDM symbol, and a fourth bit position and a fifth bit position of the seventh byte are used for defining the number of differential line pairs supported by a high-speed industrial control bus; the last three bit positions of the seventh byte are reserved fields; in the frame structure of the MAC layer, starting with the eighth byte, each byte is used to define an incremented frame number.

The control device issues the network control word by broadcasting the network control word message at the very beginning of each frame. The network control word message is the first message broadcast by the control device at the beginning of each Frame (Frame). The frame structure of the MAC layer for transmitting the network control word message is defined as shown in table 16. The field meanings in the frame structure of the MAC layer for transmitting the network control word message are shown in table 17.

Table 16 frame structure of MAC layer for transmitting network control word messages

Table 17 field meanings in the frame structure of the MAC layer for transmitting network control word messages

As shown in tables 16 and 17, the information type of the network control word message is 2; when the network control word message is transmitted through the frame structure of the MAC layer, the state mark is the system software Version number (Version) of the high-speed industrial control bus; a fourth byte, which is used for defining the serial number (FixRes _ SN) of the fixed resource used in the network currently configured by the high-speed industrial control bus; the first six bit positions of the fifth byte, which are used to define the network coding parameters (Msp, Mdmb, and Mumb), and the last two bit positions of the fifth byte, which are used to define the transmit power Ratio (Pwr-Ratio) of the upper and lower sidebands of the OFDM symbol; the first two bit positions of the sixth byte are used for defining whether the upper sideband of the OFDM symbol uses the confirmation information (Pilot) of the continuous Pilot, and the last six bit positions of the sixth byte are reserved fields (Rsvd); a first bit position of a seventh byte for defining acknowledgement information (BwCfg) for transmitting information using only the lower sideband of the OFDM symbol or for transmitting information using the entire sideband of the OFDM symbol, a second bit position of the seventh byte for defining a current network state (Mnt), a third bit position of the seventh byte for defining acknowledgement information (Sche) for uniform scheduling of the upper and lower sidebands of the OFDM symbol or independent scheduling of the upper and lower sidebands of the OFDM symbol, a fourth bit position and a fifth bit position of the seventh byte for defining the number of differential line Pairs (Pairs) supported by the high speed industrial control bus; the last three bit positions of the seventh byte are reserved field (Rsvd); in the Frame structure of the MAC layer, each byte is used to define an incremented Frame number (Frame _ Index) from the eighth byte.

The embodiment of the invention provides an information transmission method, which comprises the steps of broadcasting a reserved resource message on a high-speed industrial control bus through control equipment; the node equipment selects the matched orthogonal frequency division multiplexing OFDM symbol to send an access application message according to the information in the reserved resource message; when verifying that the access application message is legal, the control equipment sends an access response message to the node equipment; the node equipment determines a matched node identifier according to the access response message; the control equipment broadcasts an MAC unicast address message according to the node identification of each node equipment on the high-speed industrial control bus; the node equipment sends a dynamic bandwidth application message according to the node identifier; when verifying that the dynamic bandwidth application message is legal, the control equipment sends a dynamic bandwidth release message to the node equipment; the control device and the node device issue bandwidth allocation information in a message according to dynamic bandwidth, and send respective service data on the high-speed industrial control bus in the form of a message and/or a fragment message, wherein various messages transmitted on the high-speed industrial control bus follow the frame structure of an MAC layer, so that the control device and the node device hung on the high-speed industrial control bus can communicate through the frame structure of the uniform MAC layer, and the devices can understand information transmitted by other devices and can understand each other, so that the information can be transmitted through the frame structure of the MAC layer, thereby realizing dynamic addition of the node device, dynamic allocation of the node device resources, and service data communication, and realizing information transmission by using an OFDM technology, thereby realizing that the high-speed industrial control bus is a mode based on combination of time domain and frequency domain, and the control device and the node device hung on the high-speed industrial control bus can be different according to frequency, and data are sent at the same time, so that the communication efficiency is improved.

Example two

Fig. 2 is a flowchart of an information transmission method according to a second embodiment of the present invention. The present embodiment may be combined with each alternative in one or more of the above embodiments, and in the present embodiment, the method may further include: and the control equipment broadcasts and multicasts the address to issue a message according to the node identification of each node equipment on the high-speed industrial control bus.

As shown in fig. 2, the method of this embodiment specifically includes:

step 201, the control device broadcasts a reserved resource message on the high-speed industrial control bus.

Step 202, the node device selects the matched orthogonal frequency division multiplexing OFDM symbol to send the access application message according to the information in the reserved resource message.

Step 203, when the control device verifies that the access application message is legal, the control device sends an access response message to the node device.

And step 204, the node equipment determines the matched node identification according to the access response message.

And 205, the control equipment broadcasts the MAC unicast address message according to the node identification of each node equipment on the high-speed industrial control bus.

And step 206, the node equipment sends a dynamic bandwidth application message according to the node identifier.

Step 207, the control device sends the dynamic bandwidth issuing message to the node device when verifying that the dynamic bandwidth application message is legal.

And step 208, the control device and the node device send respective service data in the form of messages and/or fragment messages on the high-speed industrial control bus according to the bandwidth allocation information in the dynamic bandwidth distribution message.

And step 209, the control device broadcasts the multicast address to issue a message according to the node identification of each node device on the high-speed industrial control bus.

The multicast table is used to describe each unicast address member included in each multicast group. The form of the multicast table is shown in table 10.

Table 18 multicast table

The multicast table can be described from 2 perspectives:

A) describes which members of the multicast group each member is.

B) Describes to which multicast groups a unicast member belongs.

The frame structure of the MAC layer for transmitting the multicast address distribution packet is a frame structure used by the control device to deliver the multicast table information to all the node devices. There are three defined forms of the frame structure of the MAC layer for transmitting multicast address distribution messages.

Optionally, the control device broadcasts a multicast address to issue a message according to the node identifier of each node device on the high-speed industrial control bus; when the multicast address issuing message is transmitted through the frame structure of the MAC layer, the state mark is fragmentation information; in the frame structure of the MAC layer, the fourth byte is used for defining the node identification of a multicast member; a fifth byte, which is used for defining the minimum multicast group to which the multicast member belongs; a sixth byte, which is used for defining the maximum multicast group where the multicast members are located; in the frame structure of the MAC layer, each bit position of the set byte from the seventh byte is used to define the inclusion of multicast members in the multicast group set defined by the minimum multicast group and the maximum multicast group.

Table 19 frame structure of MAC layer for transmitting multicast address distribution packet

As shown in table 19, when the multicast address distribution packet is transmitted through the frame structure of the MAC layer, the status flag is fragmentation information (SN, EOF, and SOF); a fourth byte for defining a Node identifier (Dst _ Node) of a multicast member; a fifth byte, which is used for defining a minimum multicast Group (Min _ Group) to which the multicast members belong; a sixth byte, which is used for defining a maximum multicast Group (Max _ Group) where multicast members are located; each bit position of the set byte from the seventh byte is used to define the inclusion of the multicast members in the multicast group set defined by the minimum multicast group and the maximum multicast group.

A multicast address distribution packet transmitted using the frame structure shown in table 19 is used to describe to which multicast Group (Group) a node device belongs. The BitMap is in the form of a plurality of bytes, and each byte corresponds to one Group. If a certain byte is 1, it represents that the Dst _ Node belongs to the corresponding group. The 0 th byte in the Bitmap represents Min _ Group, and the last byte in the Bitmap represents Max _ Group. Since the minimum number of bytes in the sideband is 27bytes, it is possible to send the multicast address distribution packet by dividing it into a plurality of packets, and SN, EOF, and SOF represent fragmentation information.

Optionally, the control device broadcasts a multicast address to issue a message according to the node identifier of each node device on the high-speed industrial control bus; when the multicast address issuing message is transmitted through the frame structure of the MAC layer, the state mark is fragmentation information; in the frame structure of the MAC layer, the fourth byte is used to define a multicast group; a fifth byte, configured to define a minimum node identifier included in the multicast group; a sixth byte for defining a maximum node identifier included in the multicast group; in the frame structure of the MAC layer, each bit position of the set byte from the seventh byte is used to define the node identifier of the node device belonging to the multicast group in the set of node identifiers determined by the minimum node identifier and the maximum node identifier.

Table 20 frame structure of MAC layer for transmitting multicast address distribution packet

As shown in table 20, when the multicast address distribution packet is transmitted through the frame structure of the MAC layer, the status flag is fragmentation information (SN, EOF, and SOF); in the frame structure of the MAC layer, a fourth byte is used to define a multicast Group (Group); a fifth byte for defining a minimum Node identification (Min _ Node _ Id) included in the multicast group; a sixth byte for defining a maximum Node identification (Max _ Node _ Id) included in the multicast group; in the frame structure of the MAC layer, each bit position of the set byte from the seventh byte is used to define the node identifier of the node device belonging to the multicast group in the set of node identifiers determined by the minimum node identifier and the maximum node identifier.

The multicast address distribution message transmitted by using the frame structure shown in table 20 is used to describe which members of a certain multicast group are, and also described in the form of bitmap: the 0 th byte of the Bitmap corresponds to Min _ Node _ Id, and the last byte of the Bitmap corresponds to Max _ Node _ Id. If the multicast address issuing message exceeds the minimum sideband byte number (27bytes), the multicast address issuing message is also fragmented, and the fragmentation information is expressed by using SN, EOF and SOF.

Optionally, the control device broadcasts a multicast address to issue a message according to the node identifier of each node device on the high-speed industrial control bus; when the multicast address issuing message is transmitted through the frame structure of the MAC layer, the state mark is fragmentation information; in the frame structure of the MAC layer, the fourth byte is used to define a multicast group; a fifth byte, configured to define a total number of user nodes belonging to a multicast group included in the current message; a sixth byte for defining the total number of all user nodes belonging to the multicast group; in the frame structure of the MAC layer, in each byte from the seventh byte, a node identification of each user node belonging to the multicast group included in the current message is defined.

Table 21 frame structure of MAC layer for transmitting multicast address distribution packet

As shown in table 21, when the multicast address distribution packet is transmitted through the frame structure of the MAC layer, the status flag is fragmentation information (SN, EOF, and SOF); in the frame structure of the MAC layer, a fourth byte is used to define a multicast Group (Group); a fifth byte, configured to define a total number of user nodes (Node _ Num) belonging to the multicast group included in the current message; a sixth byte for defining the Total number of all user Nodes (Total _ Nodes) belonging to the multicast group; in the frame structure of the MAC layer, in each byte from the seventh byte, a node identification of each user node belonging to the multicast group included in the current message is defined.

The multicast address distribution message transmitted by using the frame structure shown in table 21 is used to describe which members of a certain multicast group are expressed by directly using a set of several node identifiers. Node _ Num indicates that the multicast group has several members, and the Node id array lists the Node identification of each member in turn.

Optionally, the information type of the multicast address issue packet is 4.

The embodiment of the invention provides an information transmission method, which broadcasts a multicast address issuing message through a control device according to a node identifier of each node device on a high-speed industrial control bus, and can transmit the multicast address issuing message to all the node devices through a frame structure of an MAC layer for transmitting the multicast address issuing message.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An information transmission method is applied to control equipment and node equipment which are hung on a high-speed industrial control bus, and comprises the following steps:

the control equipment broadcasts a reserved resource message on the high-speed industrial control bus;

when the control equipment verifies that the access application message is legal, the control equipment sends an access response message to the node equipment;

the node equipment sends a dynamic bandwidth application message according to the node identification;

when the control equipment verifies that the dynamic bandwidth application message is legal, sending a dynamic bandwidth release message to the node equipment;

wherein, various messages transmitted on the high-speed industrial control bus follow the frame structure of an MAC layer;

in the frame structure of the MAC layer, a first byte is used for defining an information type, all of a second byte and a set bit position in a third byte and is used for defining an information length, the rest bit positions in the third byte are used for defining a status mark, and at least one byte from a fourth byte is used for defining other information matched with the information type;

when the service data in the form of a fragment message is transmitted through the frame structure of the MAC layer, the state mark is fragment information;

in the frame structure of the MAC layer, a fourth byte is used to define a node identifier of a source node, a fifth byte is used to define a node identifier of a destination node, and starting from the sixth byte, information payload is defined.

2. The method of claim 1, wherein:

in the frame structure of the MAC layer, all of the second byte and the first two bit positions of the third byte are used to define the information length, and the remaining six bit positions of the third byte are used to define the status flag.

3. The method of claim 1, wherein the status flag is a reserved field when a reserved resource packet is broadcast through a frame structure of the MAC layer;

in the frame structure of the MAC layer, a fourth byte is used for defining the serial number of reserved resources used in the network currently configured by the high-speed industrial control bus;

in the frame structure of the MAC layer, a fifth byte is used to define the number of reserved resources that are available in the current network; a sixth byte, configured to define an offset of the reserved resource in the current information in the reserved resource allocation table; a seventh byte for defining the number of reserved resources in the current information;

in the frame structure of the MAC layer, starting from the eighth byte, taking six bytes as a unit, and respectively defining a reserved resource allocation table entry under each unit;

in each reserved resource allocation table entry, a first byte is used for defining a node identifier of a source node of a reserved resource, a second byte is used for defining a node identifier of a destination node of the reserved resource, a third byte is used for defining a resource type of the reserved resource, the first six bit positions in a fourth byte are used for defining the number of time slots of the reserved resource, the last two bit positions of the fourth byte are used for defining acknowledgement information that the reserved resource only uses an upper sideband, only uses a lower sideband or uses all sidebands, all of the fifth byte and the first bit position of the sixth byte are used for defining the time slot position of the reserved resource, the second bit position to the fifth bit position of the sixth byte are reserved fields, and the last three bit positions of the sixth byte are used for defining the cycle period of the reserved resource.

4. The method of claim 1, wherein the status flag is a reserved field when transmitting an access request packet through a frame structure of the MAC layer;

in the frame structure of the MAC layer, a fourth byte is used to define a node identifier of the node device that issued the access application;

in the frame structure of the MAC layer, the first four bit positions of a fifth byte are used to define the current operating state of the node device, the fifth bit position of the fifth byte is used to define whether the node device receives the acknowledgement information of a complete fixed resource allocation table, the sixth bit position of the fifth byte is used to define whether the node device receives the acknowledgement information of a complete multicast table, and the last two bit positions of the fifth byte are reserved fields;

in the frame structure of the MAC layer, a sixth byte is configured to define the number of other node devices that can be monitored by the node device, and a seventh byte is configured to define, when a fifth bit position of the fifth byte defines that acknowledgement information of a complete fixed resource allocation table is received, a sequence number of a latest fixed resource received by the node device;

in the frame structure of the MAC layer, an eighth byte is used to define a device type of the node device, and all bit positions of the ninth byte to the twelfth byte are used to define a MAC address of the node device.

5. The method of claim 1, wherein the status flag is a reserved field when transmitting an access response packet through a frame structure of the MAC layer;

in the frame structure of the MAC layer, the fourth byte is used to define a node identifier allocated to a node device that sends an access application; a fifth byte for defining an action type of the access response; all bit positions of the sixth byte to the eleventh byte are used for defining the media access control address of the node device.

6. The method according to claim 1, wherein the status flag is a reserved field when transmitting a MAC unicast address issue packet through a frame structure of the MAC layer;

in the frame structure of the MAC layer, a fourth byte is used to define the number of operations matching the adding or deleting operations of the node devices in the network, and a fifth byte is used to define the number of node devices in a running state in the current network;

in the frame structure of the MAC layer, a sixth byte is used to define an offset of a MAC table in current information in a complete MAC table; a seventh byte for defining the number of MAC table entries included in the current information;

in the frame structure of the MAC layer, starting from the eighth byte, seven bytes are taken as a unit, and MAC table entries are respectively defined under each unit; in the MAC table entry, the first byte is a node identifier of the node device, and the last six bytes are an MAC address of the node device.

7. The method according to claim 1, wherein the status flag is a reserved field when transmitting a dynamic bandwidth application message through a frame structure of the MAC layer;

in the frame structure of the MAC layer, a fourth byte is used for defining a node identifier of a source node applying for a dynamic bandwidth; a fifth byte, which is used for defining the node identification of the destination node applying for the dynamic bandwidth; a sixth byte, which is used for defining the service type of the application dynamic bandwidth; a seventh byte for defining the number of time slots for applying for the dynamic bandwidth; the first three bit positions of the eighth byte are used for defining the real-time priority of applying for the dynamic bandwidth, and the last five bit positions of the eighth byte are reserved fields.

8. The method according to claim 1, wherein the status flag is a reserved field when transmitting a dynamic bandwidth distribution packet through a frame structure of the MAC layer;

in the frame structure of the MAC layer, a fourth byte is used to define the number of dynamic resources included in the information;

in the frame structure of the MAC layer, starting from the fifth byte, taking the five bytes as a unit, and respectively defining the description information of each dynamic resource under each unit;

in the description information of the dynamic resource, a first byte is used for defining a node identification of a source node of the dynamic resource, a second byte is used for defining a node identification of a destination node of the dynamic resource, a third byte is used for defining a service type of the dynamic resource, the first six bit positions of a fourth byte are used for defining a time slot length of the dynamic resource, the last two bit positions of the fourth byte are used for defining acknowledgement information of the dynamic resource using only an upper sideband, only a lower sideband or all sidebands, the first six bit positions of a fifth byte are used for defining a time slot position of the dynamic resource, and the last two bit positions of the fifth byte are reserved fields.

9. The method of claim 1, further comprising:

the control equipment broadcasts a network control word message at the initial position of each frame;

when a network control word message is transmitted through the frame structure of the MAC layer, the state mark is the system software version number of the high-speed industrial control bus;

in the frame structure of the MAC layer, a fourth byte is used for defining the sequence number of a fixed resource used in a network currently configured by the high-speed industrial control bus;

in the frame structure of the MAC layer, the first six bit positions of a fifth byte are used for defining network coding parameters, and the last two bit positions of the fifth byte are used for defining the transmitting power proportion of upper and lower sidebands of an OFDM symbol;

in the frame structure of the MAC layer, the first two bit positions of the sixth byte are used to define the acknowledgement information whether the upper sideband of the OFDM symbol uses continuous pilots, and the last six bit positions of the sixth byte are reserved fields;

in the frame structure of the MAC layer, a first bit position of a seventh byte is used to define acknowledgement information that information is transmitted only using a lower sideband of an OFDM symbol or information is transmitted using an entire sideband of the OFDM symbol, a second bit position of the seventh byte is used to define a current network state, a third bit position of the seventh byte is used to define acknowledgement information that an upper sideband and a lower sideband of the OFDM symbol are uniformly scheduled or that an upper sideband and a lower sideband of the OFDM symbol are independently scheduled, and a fourth bit position and a fifth bit position of the seventh byte are used to define the number of differential line pairs supported by the high-speed industrial control bus; the last three bit positions of the seventh byte are reserved fields;

in the frame structure of the MAC layer, starting with the eighth byte, each byte is used to define an incremented frame number.