CN214011767U - 485 bus-based networking control system - Google Patents

Abstract

The utility model relates to the technical field of industrial automation, in particular to a 485 bus-based networking control system, which is provided with a microprocessor, wherein the microprocessor is connected with a temperature acquisition circuit, an annular data receiving area and an annular data sending area; the isolation module is connected with the microprocessor through data analysis, and the data analysis is connected with DMA serial port receiving interrupt and DMA serial port sending interrupt; the environment illumination acquisition circuit and the power management circuit are arranged, the environment illumination acquisition circuit and the power management circuit are both connected with the microprocessor, and the power management circuit is connected with an EMC circuit. The utility model discloses be applied to 485 bus network deployment control under the industrial environment for the data management of bus becomes to simplify, easy operation.

Description

485 bus-based networking control system

Technical Field

The utility model relates to an industrial automation technical field, concretely relates to network deployment control system based on 485 buses.

Background

Under the current environment that modern industrial production is developed day by day, computers occupy increasingly important positions by virtue of strong processing capacity and real-time communication capacity.

With the mode that industrial automation control gradually replaces manual intervention, the control and management of remote equipment are realized, efficient and stable data communication cannot be avoided, control signals are sent to a receiving end of the equipment in real time, meanwhile, the operation condition of the equipment end needs to be monitored in real time, and all control and detection cannot be conducted without interactive transmission of real-time data.

Compared with parallel communication, 485 communication has the characteristics of less transmission lines, long transmission distance, simple connection, high data transmission reliability and the like although the communication speed is low, so that the 485 communication is widely applied to a data communication network, and a special controller needs to be designed for data distribution and retrieval when all devices are cascaded based on a 485 communication bus mode.

Aiming at the situation that under the current industrial environment, when the 485 bus carries out communication networking control, data transmission on the reasonable and efficient management bus is designed, and a set of new control mode is designed.

SUMMERY OF THE UTILITY MODEL

Not enough to prior art, the utility model discloses a networking control system based on 485 bus aims at being applied to 485 bus networking control under the industrial environment for the data management of bus becomes to simplify, easy operation.

The utility model discloses a following technical scheme realizes:

the utility model discloses a 485 bus-based networking control system, which is provided with a microprocessor, wherein the microprocessor is connected with a temperature acquisition circuit, an annular data receiving area and an annular data sending area; the isolation module is connected with the microprocessor through data analysis, and the data analysis is connected with DMA serial port receiving interrupt and DMA serial port sending interrupt; the environment illumination acquisition circuit and the power management circuit are arranged, the environment illumination acquisition circuit and the power management circuit are both connected with the microprocessor, and the power management circuit is connected with an EMC circuit.

Furthermore, the 485 isolation module adopts 1 uplink 485 communication module and 2 downlink 485 communication modules.

Furthermore, the uplink DMA serial port of the control system receives and sends control commands from the user side.

Furthermore, the downlink DMA serial port of the control system transmits and receives data to and from the slave device.

Furthermore, the microprocessor is used for receiving the dynamic memory application of the line ring data area and receiving or deleting the data according to the data storage state in the ring buffer area.

The utility model has the advantages that:

the utility model discloses quote annular data receiving and dispatching mechanism, all data are all queued through annular buffer and are listed as, and the system is also according to the order of stacking successively of data, carries out the analytic processing of data, and the designer can be according to the size of actual data volume, and the speed of the analytic data of system carries out the settlement of annular receiving and dispatching buffer size, and the maximum optimization system configuration resource, application that can be better is in multichannel 485 passageways and need carry out data access's design application to server and multiple-path equipment from the machine simultaneously, the utility model relates to a framework is clear, understandable, has also reached better control effect in practical application.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a circuit schematic diagram of a 485 bus based barrier lamp synchronous flashing system.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

The embodiment discloses a 485 bus-based networking control system as shown in fig. 1, which is provided with a microprocessor, wherein the microprocessor is connected with a temperature acquisition circuit, an annular data receiving area and an annular data sending area; the isolation module is connected with the microprocessor through data analysis, and the data analysis is connected with DMA serial port receiving interrupt and DMA serial port sending interrupt; the environment illumination acquisition circuit and the power management circuit are arranged, the environment illumination acquisition circuit and the power management circuit are both connected with the microprocessor, and the power management circuit is connected with an EMC circuit.

The 485 isolation module of this embodiment adopts 1 way of ascending 485 communication modules and 2 ways of descending 485 communication modules.

In this embodiment, the uplink DMA serial port of the control system receives and sends the control command from the user side. And a downlink DMA serial port of the control system transmits and receives data to and from the slave equipment.

The microprocessor of this embodiment is configured to receive a dynamic memory application in the row ring data area, and receive or delete this data according to a data storage state in the ring buffer area.

Before explaining the design idea of the embodiment, a brief control description is given on the current bus control mode, the networking of the conventional 485 communication bus is generally realized in a mode that a plurality of devices are externally hung on a controller under a communication module, the controller is a host, the devices are slaves, each device has a unique device ID address, the 485 communication module with signal isolation can be externally hung with 30 device addresses at most, and the number of the devices far exceeds the number during actual use.

Meanwhile, when a user needs to remotely manage and control equipment, the user often only can control the controllers integrally, and the user wants to control the slave equipment hung outside each controller, so that the control is difficult to realize.

In this embodiment, aiming at the technical problem of actual control that needs to be faced when actually controlling, a unique design idea and a control method of the 485 bus networking controller are provided, and data transmission management and analysis are performed on a hardware circuit and a software control architecture, where a main unit of the controller system includes: the microprocessor is mainly responsible for the operation and management operation of the whole system, the operating system running in the chip adopts an open source system which is widely applied at present, namely a FREERTOS real-time operating system, and mainly utilizes a system high-efficiency real-time multi-task management kernel, and after cutting and optimization, the operating system occupies smaller microprocessor hardware resources.

In the embodiment, 485 communication is mainly considered as a half-duplex data communication mode, and a control mode of sending and responding delay waiting exists, so that the normal operation of other system tasks cannot be interrupted due to the response delay waiting when the whole system receives, sends and analyzes the communication data of the bus;

the isolation RS485 communication unit has the advantages that the use environment of the RS485 bus is very complex, and high voltage exists in severe use occasions. The danger of electric shock is easily generated, and the safety of people or equipment is endangered.

In many practical applications, the communication distance can reach several kilometers, and the distance between nodes is very long. Designers often connect the reference ground of each node directly to the local earth, as the return ground of the signal, which seems to be a normal and reliable practice, but has a great hidden trouble! Even with a normal system, various problems may arise after a period of use.

The problems that are often ignored are: there may also be a large potential difference between the two nodes, the actual earth is not the ideal "0" potential, the earth is also a conductor, and there is also impedance. When a large current flows through the earth, a potential difference also exists across the earth through which the current flows.

If the communication nodes which are far away from each other are directly connected to respective local grounds, the ground potential difference is superimposed on the output end of the bus transmitter in the form of common mode voltage, and the superimposed signal may far exceed the common mode input voltage range which can be borne by the receiver, so that the signal cannot be normally received, and the transceiver is seriously damaged.

Common mode input ranges of common CAN and RS-485 transceivers are small, for example, SN65HVD251 and SP3085 transceivers only support common mode input ranges of-7V to +12V, and large current injected by various large-scale equipment flows through the earth, so that the earth potential difference caused by the large current CAN reach several volts, dozens of volts or even hundreds of volts and is far beyond the voltage range which CAN be born by the transceivers.

The isolation transceiver can electrically isolate the bus from the control circuit, and high voltage is blocked outside the control system, so that the personal safety and the system safety of operators can be effectively ensured. Moreover, the isolation can suppress various common-mode interferences caused by the ground potential difference and the ground loop, and ensure that the bus operates uninterruptedly and without errors under the conditions of serious interferences and other system-level noises.

After the isolation transceiver is used, a ground loop can be effectively prevented from being formed, the bus reference ground can fluctuate along with fluctuation of common-mode voltage, the common-mode voltage is borne by the isolation band, and common-mode voltage becomes invisible to bus signals, so that stable and reliable communication of the bus is guaranteed.

There are two main methods for realizing bus isolation, one is to use discrete devices such as isolation DC-DC, optical coupler, etc. to realize isolation between nodes and transceivers. By using the method, the circuit is complex, the volume is large, and the requirement of high integration degree of the current electronic products is difficult to meet. The other type is that an isolation transceiver is directly used, a single product is adopted, the design is simple, and the integration level is high.

In this embodiment, 1 uplink 485 communication module and 2 downlink 485 communication modules are adopted, and the number of the downlink communication modules can be expanded according to actual conditions during actual design and development. And the golden sun rise single-path high-speed high-isolation RS485 isolation receiving and transmitting module is adopted, so that 3.75kVAC electrical isolation at two ends can be realized, and the reliability of bus communication is ensured.

The uplink serial port data receiving unit of the embodiment mainly receives and sends control commands from a user side, and the system mainly adopts a DMA receiving mode, so that the burden of the system can be reduced to the greatest extent. The downlink serial port receiving data unit is mainly used for transmitting and receiving data to and from the slave equipment, and a DMA (direct memory access) receiving mode is adopted for a plurality of communication modules under the consideration, so that the system load can be reduced to the greatest extent.

In this embodiment, a set of ring data buffer areas, namely an uplink ring data buffer area and a downlink data buffer area, is specially designed for receiving uplink and downlink serial data, and the whole buffer area sequentially queues all received serial data into a stack in a data push manner.

When the system receives effective data, firstly, the dynamic memory application of the annular data area is carried out, if the data in the annular buffer area is full, the received data is automatically discarded, and the data coverage problem can not occur, so that the maximum data pressure test needs to be considered during system design, and the sufficient buffer area is ensured to carry out data buffering. And if the interior of the ring buffer is not full, the received new data is pressed into the buffer area, and queuing and data analysis processing are carried out.

When queuing processing of data in the buffer area is carried out, analysis processing is carried out according to a first-in first-out mechanism, corresponding equipment port numbers are automatically identified through identifying the ID numbers of data of each frame to carry out data packet transferring transmission, when response is waited, the data fed back by the ports are also identified through the ID numbers, and then the data are packed and pressed into the buffer area to carry out data queuing and wait for data processing of a system.

To sum up, the utility model discloses the core design thinking lies in quoting annular data receiving and dispatching mechanism, and all data are queued to be listed in through annular buffer, and the system also stacks the order according to the precedence of data, carries out the analytic processing of data, and the designer can carry out the settlement of annular receiving and dispatching buffer size, the maximum optimization system configuration resource according to the size of actual data volume, the analytic data's of system speed.

The utility model discloses 485 communication network deployment thinking, can be better use at multichannel 485 passageways, and need simultaneously to server and multiple-way equipment from the machine carry out data access's design and application, the design framework is clear, understandable, has also reached better control effect in practical application.

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims (5)

1. A485 bus-based networking control system is characterized by comprising a microprocessor, wherein the microprocessor is connected with a temperature acquisition circuit, an annular data receiving area and an annular data sending area; the isolation module is connected with the microprocessor through data analysis, and the data analysis is connected with DMA serial port receiving interrupt and DMA serial port sending interrupt; the environment illumination acquisition circuit and the power management circuit are arranged, the environment illumination acquisition circuit and the power management circuit are both connected with the microprocessor, and the power management circuit is connected with an EMC circuit.

2. The 485-bus-based networking control system according to claim 1, wherein the 485 isolation module employs 1 uplink 485 communication module and 2 downlink 485 communication modules.

3. The 485-bus-based networking control system according to claim 1, wherein an upstream DMA serial port of the control system receives and transmits control commands from a user side.

4. The 485-bus-based networking control system according to claim 1, wherein a downstream DMA serial port of the control system transmits and receives data to and from a slave device.

5. The 485-bus-based networking control system according to claim 1, wherein the microprocessor is configured to receive a dynamic memory application from the row ring data area, and receive or delete the current data according to a data storage state in the ring buffer area.

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