CN107168264B - The serial ports shared system and method for environmental monitoring - Google Patents

Abstract

The invention provides a serial port sharing system for environmental monitoring. The system includes: a serial port, at least one environmental monitoring instrument, multiple industrial control machines and a processing module. The processing module divides the serial port time occupied by each environmental monitoring instrument and the corresponding industrial control machine session to obtain multiple time slots, and in one time slot, an industrial control machine transmits network data to the corresponding environmental monitoring machine through the serial port instrument, the environmental monitoring instrument receives and responds to the network data, and returns the network data to the industrial control machine. In addition, the present invention also provides a serial port sharing method for environmental monitoring. The present invention realizes data collection and control of multiple instruments at the same time, and also supports serial port communication access of multiple industrial control machines to at least one environmental monitoring instrument.

Description

Serial port sharing system and method for environmental monitoring

technical field

The invention relates to the technical field of serial port communication for environmental monitoring, in particular to a serial port sharing system and method for environmental monitoring.

Background technique

In the field of environmental monitoring, at present, various environmental monitoring instrument manufacturers provide their own serial communication control software, but the communication standards are different, the program operation design is complicated, and the parameter settings are also different.

The main communication mode of current environmental monitoring instruments is serial port communication (RS232), and only one communication serial port interface provides data communication service. Because the serial port design is exclusive, such a structure can only satisfy a data acquisition device to communicate with the monitoring instrument.

Contents of the invention

(1) Technical problems to be solved

The object of the present invention is to provide a serial port sharing system and method for environmental monitoring, so as to solve at least one of the above technical problems.

(2) Technical solution

The invention provides a serial port sharing system for environmental monitoring, comprising:

The serial port includes a first end, the first end includes at least one first interface; and a second end, the second end includes a plurality of second interfaces;

At least one environmental monitor, used to electrically connect to the first interface;

A plurality of industrial control machines are used to electrically connect the second interface, and each environmental monitor corresponds to a plurality of industrial control machines, and communicates through the serial port;

The processing module is electrically connected to the serial port, and is used to divide the serial port time occupied by each industrial control machine and the corresponding environmental monitor session to obtain multiple time slots t, and in one time slot, an industrial control machine The network data is transmitted to the corresponding environmental monitoring instrument through the serial port, and the environmental monitoring instrument receives and responds to the network data, and returns the network data to the industrial control machine.

Optionally, the processing module is also used to set the priority levels of the industrial control machines, so that the industrial control machines of different priority levels have conversations with the corresponding environmental monitors in different time slots.

Optionally, the time slot t=time required for serial port data transmission _t1 +serial port response waiting time _t2 +network transmission time _{t3 +} data processing time t4 ₊ serial port return data time t5, wherein _t2≤50ms .

Optionally, the processing module is also used for: if the serial port responds to the industrial control machine within the time period _t2 , then put the network data into the buffer, and within the time period _t3 and _t4 , send the network data The data is returned to the corresponding environmental monitoring instrument, the environmental monitoring instrument receives and responds to the network data, and returns the network data to the industrial control machine, thereby ending the session and releasing the serial port for the next session; if the serial port is not If the industrial control machine does not respond within the time period of _t2 , the session will be terminated directly, and the serial port will be released for the next session.

Optionally, the system also has a communication log recording function: you can check the communication status of each serial port, the command interval time, whether the serial port is idle, and the record of communication failure.

Based on the same inventive concept, the present invention also provides a serial port sharing method for environmental monitoring, the method is applied to the aforementioned serial port sharing system for environmental monitoring, including steps:

The processing module divides the serial port time occupied by the sessions of each industrial control machine and the corresponding environmental monitor to obtain multiple time slots t;

In each time slot, an industrial control machine transmits network data to the corresponding environmental monitor through the serial port, and the environmental monitor receives and responds to the network data, and returns the network data to the industrial control machine.

Optionally, the time slot t=time required for serial port data transmission _t1 +serial port response waiting time _t2 +network transmission time _{t3 +} data processing time t4 ₊ serial port return data time t5, wherein _t2≤50ms .

Optionally, if the serial port responds to the industrial control machine within the time period of _t2 , put the network data into the buffer, and return the network data to the corresponding environmental monitoring instrument within the time period of _t3 and _t4 , the environmental monitoring instrument receives and responds to the network data, and returns the network data to the industrial control machine, thereby ending the session and releasing the serial port for the next session; if the serial port does not respond within the _t2 time period The industrial control machine directly ends the session, and releases the serial port for the next session.

Optionally, in a time slot, when an industrial control machine is having a session, the industrial control machine not in the session sends network data to the serial port, and the network data enters a queue and waits for transmission in the next time slot in turn.

Optionally, the maximum delay of the waiting time-slot conversation queue of the industrial control machine that is not in conversation = the serial port time occupied by a single time-slot * the number of queues accessing this serial port, wherein the maximum delay of the time-slot conversation queue is ≤ 1s.

(3) Beneficial effects

Compared with the prior art, the present invention has the following advantages:

1. The serial port sharing system for environmental monitoring provided by the present invention performs communication optimization and debugging for environmental monitoring instruments, and provides a complete communication protocol stack library for environmental monitoring instruments to realize support for proprietary communication protocols. The communication data can be intelligently selected and judged to ensure stable and reliable data communication and meet the needs of various industrial production environments.

2. The serial port sharing method for environmental monitoring provided by the present invention adopts time-division communication technology to divide time slots, ensuring the separate transmission of data, satisfying the simultaneous data collection and control of multiple instruments and supporting multiple industrial control machines for at least one The serial port communication access of the environmental monitoring instrument can easily realize simultaneous data acquisition and operation control of multiple instruments.

3. The present invention provides management software access control, which can complete the communication parameter setting through the LAN (Local Area Network) port, which is convenient for operation.

Description of drawings

Fig. 1 is the overall structural representation of the serial port sharing system of the environmental monitoring of the embodiment of the present invention;

2 is a schematic structural diagram of a serial port sharing system for environmental monitoring in a detailed embodiment of an embodiment of the present invention;

Fig. 3 is the schematic diagram of the serial port occupation time of the access queue of the embodiment of the present invention;

FIG. 4 is a schematic diagram of time slots according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of steps of a serial port sharing method for environmental monitoring according to an embodiment of the present invention.

Detailed ways

In the prior art, the main communication mode of current environmental monitoring instruments is serial port communication (RS232), and there is only one communication serial port interface to provide data communication services. Transmission with a lower computer. However, in actual production and application scenarios, it is often necessary to exchange data between multiple acquisition devices and monitoring instruments, that is, multiple upper computers need to realize data communication with one or even multiple lower computers through a serial port. Therefore, the present invention A serial port sharing system and method for environmental monitoring are provided, thereby fulfilling the requirement of realizing one-to-many or even many-to-many serial port communication through one serial port. Its design meets the data acquisition requirements of environmental monitoring instruments, and is used to solve the practical problem of shared communication between multiple industrial control data acquisition equipment and at least one monitoring instrument, and can be widely used in the field of environmental automation monitoring.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

Figure 1 is a schematic diagram of the overall structure of a serial port sharing system for environmental monitoring according to an embodiment of the present invention. As shown in Figure 1 , an aspect of the embodiment of the present invention provides a serial port sharing system for environmental monitoring, including:

The serial port includes a first end, the first end includes at least one first interface; and a second end, the second end includes a plurality of second interfaces;

At least one environmental monitor, used to electrically connect to the first interface;

A plurality of industrial control machines are used to electrically connect the second interface, and each environmental monitor corresponds to a plurality of industrial control machines, and communicates through the serial port;

The processing module is electrically connected to the serial port, and is used to divide the serial port time occupied by each industrial control machine and the corresponding environmental monitor session to obtain multiple time slots t, and in one time slot, an industrial control machine The network data is transmitted to the corresponding environmental monitoring instrument through the serial port, and the environmental monitoring instrument receives and responds to the network data, and returns the network data to the industrial control machine. Generally speaking, the processing module can be realized by software programs or other programmable data processing devices. In addition, a serial port sharing system for environmental monitoring may also have multiple serial ports and processing modules controlling them, so as to realize monitoring communication between more devices.

In one embodiment of the present invention, two environmental monitoring instruments are selected, and four industrial control machines respectively corresponding to the two environmental monitoring instruments, Fig. 2 is a detailed embodiment of the environmental monitoring of the embodiment of the present invention The structural diagram of the serial port sharing system, as shown in Figure 2, the serial port sharing system includes a serial port, the first end of the serial port includes 2 first interfaces (COM1 and COM2), and the second end has 4 second interfaces (COM11, COM12, COM21 and COM22). COM1 and COM2 are respectively connected to the environmental monitoring instrument 1 and the industrial control machine 2, COM11 and COM12 are respectively connected to the environmental monitoring instrument 1 for a communication session, and COM21 and COM22 are respectively connected to the industrial control machine 2 for a communication session. Among them, each connection mode of the equipment adopts RS232 serial port cable, the serial port communication is 9600 baud rate, 8 bits, no parity.

In addition, the processing module is also connected to the serial port, and is used for the environmental monitoring instrument 1 and its corresponding industrial control machine 11 and industrial control machine 12, as well as the industrial control machine 2 and its corresponding industrial control machine 21 and industrial control machine 22. The serial port time occupied during the conversation is divided to obtain 4 time slots t, and in one time slot, an industrial control machine transmits network data to the corresponding environmental monitoring instrument through the serial port, and the environmental monitoring instrument receives and responds to the network data, and return the network data to the industrial control machine. In addition, the system can also have a communication log recording function: you can check the communication status of each serial port, the command interval time, whether the serial port is idle, the record of communication failure, etc.

The processing module can also be used to set the priority level of the industrial control machine. The processing module can set working parameters, such as: TimeOut, the model of the environmental monitoring instrument, the identifier of the end of communication, etc. For example, it can be set in the communication with the environmental monitoring instrument The priority of the industrial control machine 11 is higher than that of the industrial control machine 12, so that the priority communication of the industrial control machine 11 can be ensured. When the industrial control machine 11 and the industrial control machine 12 receive instructions at the same time and prepare to send data to start the session, the industrial control machine 11 takes priority; the command cache of the industrial control machine 12 is blocked, and the serial port is idle to send. When the industrial control machine 11 responds to the data end mark (such as 0D), the instrument can be regarded as idle when there is no other data in the last 500ms; when the instrument is idle, the idle serial port can forward the data of the industrial control machine 22.

The invention utilizes time-division communication technology to define a query serial port access as a session, and the serial port time occupied by a session is defined as a time slot. By reasonably allocating time slots for different devices, the serial port access of multiple devices can be realized. The invention is also applicable to query-type serial port access. The upper computer starts a time slot session when it sends network data. Before the time slot session is completed, it cannot be interrupted by other devices, ensuring the integrity of the serial port data. In addition, after a time slot session completes the serial port sending and receiving process, it will immediately return the obtained data to the corresponding device. If no data is obtained, it will wait for the device to start the next time slot session. Regardless of whether data is obtained or not, after the slot session is completed, the serial port will be released for other devices. In order to ensure that all devices can get data fairly, even if the serial port is occupied by a time slot session, other devices can also send network data to the shared serial port server. At this time, the data will enter the queue. When the working time slot session is completed, That is, this data can be used to start new sessions for other devices. Fig. 3 is the schematic diagram of the serial port occupation time of the access queue of the embodiment of the present invention, as shown in Fig. 3, 4 industrial control machines visit a serial port at the same time, time slot session A-D corresponds to the conversation of 4 industrial control machines with the environmental monitoring instrument respectively , The data transmission between the 4 industrial control machines is completely isolated.

In a time slot, when an industrial control machine is having a conversation, other industrial control machines send network data to the serial port, and the network data enters the queue, waiting for transmission in the next time slot in turn. And the maximum delay of the waiting time slot session queue of the industrial control machine=single time slot occupied serial port time*the number of queues accessing this serial port, wherein, the maximum delay of the time slot session session queue is ≤1s. If the maximum delay of the time slot session queue is greater than 1s, the waiting time of the industrial control machine in the queue is overtime, and at this time, the industrial control machine needs to re-enter the queue to wait again.

At present, all kinds of environmental monitoring instrument manufacturers provide their own serial communication control software, but the communication standards are different, the program operation design is complicated, and the parameter settings are also different. The serial port sharing system for environmental monitoring provided by the present invention can integrate and package the current mainstream instrument communication protocols with the underlying communication protocols of various current monitoring equipment, uniformly plan the communication interfaces for equipment data collection, control, communication, and processing, and unify abstract monitoring The equipment management control model provides a stable and reliable core data communication core framework for the data retrieval of the upper-level business system. The industrial control machine can use ARM7TDMI embedded processor and Linux operating system, two monitors with actual operating environment Linux, and use CentOS 6.5 management system.

In the application of environmental automation monitoring system, the serial port sharing system of environmental monitoring provided by the present invention provides management software access control, completes communication parameter setting through LAN port, and the environmental monitoring equipment that has been packaged is as follows: Thermo 42i (NO/NO2 /Nox monitor), Thermo 43i (SO2 monitor), Thermo 48i (CO monitor), Thermo 49i (O3 monitor), T-API M100E (SO2 monitor), T-API M200E (NO/NO2/Nox monitor), T-API M300E (CO monitor), T-API M400E (O3 monitor), Thermo 1400ab (PM10 monitor) and Thermo1405F (PM2.5 monitor). In other embodiments, other environmental monitoring devices can be constructed based on the serial port sharing system for environmental monitoring provided by the present invention, which will not be repeated here.

Fig. 4 is the time slot schematic diagram of the embodiment of the present invention, as shown in Fig. 4, described time slot t=serial port transmits data required time _t1 +serial port waits for response time _t2 +network transmission time _t3 +device processing data time t ₄ + the time t ₅ when the serial port returns data to the environmental monitoring instrument. Generally speaking, the time t ₁ required for the serial port to transmit data is equal to the time t ₅ for the serial port to return the data to the environmental monitoring instrument. In addition, the t ₂ is ≤50ms. If the serial port responds to the industrial control machine within the _t2 time period, the network data is put into the buffer, and within the _t3 and _t4 time period, the network data is returned to the environmental monitoring instrument in conversation with it, the The environmental monitoring instrument receives and responds to the network data, and returns the network data to the industrial control machine, thereby ending the session and releasing the serial port for the next session _; More than 50ms) does not respond to the industrial control machine, and no longer transmits the network data, the session will be ended directly, and the serial port will be released for the next session.

Another aspect of the embodiment of the present invention also provides a serial port sharing method for environmental monitoring. The method is applied to the above-mentioned serial port sharing system. FIG. 5 is a schematic diagram of the steps of the serial port sharing method for environmental monitoring in the embodiment of the present invention, as As shown in Figure 5, the method includes steps:

S1. The processing module divides the serial port time occupied by the sessions of each industrial control machine and the corresponding environmental monitoring instrument to obtain multiple time slots t;

Step S1 uses time-division communication technology to define a query serial port access as a session, and the serial port time occupied by a session is defined as a time slot. By reasonably allocating time slots for different devices, the serial port access of multiple devices can be realized. Among them, the time slot t = the time required for serial port to transmit data t ₁ + serial port waiting response time t ₂ + network transmission time t ₃ + device processing data time t ₄ + time for serial port to return data to environmental monitoring instrument t ₅ , and t ₂ ≤50ms, if the serial port waits for a response for more than 50ms, the session will be ended directly, and the serial port will be released for the next session.

S2. In each time slot, an industrial control machine transmits network data to the corresponding environmental monitor through the serial port, and the environmental monitor receives and responds to the network data, and returns the network data to the industrial control machine.

In addition, the present invention can also ensure that all devices can obtain data fairly. Even if the serial port is occupied by a time slot session, other devices can send network data to the shared serial port server. At this time, the data will enter the queue. When the working time slot session is completed, this data can be used to start a new session for other devices. The serial port sharing method for environmental monitoring adopts time-division communication technology to divide the time slots, ensuring the separate transmission of data, satisfying the simultaneous data collection and control of multiple instruments, and supporting the serial port communication of multiple industrial control machines to at least one environmental monitoring instrument Access to realize simultaneous data acquisition and operation control of multiple instruments.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (9)

1. a kind of serial ports shared system of environmental monitoring characterized by comprising

Serial ports, including first end, the first end include at least one first interface；And second end, the second end include Multiple second interfaces；

At least one environment monitor, for being electrically connected the first interface；

Multiple Industrial Control Computers, for being electrically connected the second interface, and each environment monitor and multiple industry are controlled Machine processed is corresponding, is conversated by the serial ports；

Processing module is electrically connected with the serial ports, for shared by each Industrial Control Computer and corresponding environment monitor session The serial ports time is divided, and multiple time slot t are obtained；And the priority level of setting Industrial Control Computer, to realize difference Each Industrial Control Computer of priority level conversates in different time slots with corresponding environment monitor respectively；

And in a time slot, an Industrial Control Computer transmits network data to corresponding environment monitor, the ring by the serial ports Border monitor receives and responds the network data, and the network data is back to the Industrial Control Computer.

2. system according to claim 1, which is characterized in that t the time required to the time slot t=serial ports transmission data₁+ string Mouth response waiting time t₂+ network latency t₃+ data processing time t₄+ serial ports returned data time t₅, wherein t₂≤50ms。

3. system according to claim 2, which is characterized in that the processing module is also used to: if serial ports is in t₂In period Industrial Control Computer is responded, then the network data is put into buffer area, and in t₃With t₄In period, the network data is returned To corresponding environment monitor, which receives and responds the network data, and the network data is back to this Industrial Control Computer carries out session next time to terminate this session and discharge serial ports；If serial ports is not in t₂It is not rung in period Industrial Control Computer is answered, then directly terminates this session, and discharge serial ports, carries out session next time.

4. system according to claim 1, which is characterized in that the system also has communication log writing function: can check The communication state of each serial ports, the command interval time, whether serial ports idle and record of Communications failure.

5. a kind of serial ports sharing method of environmental monitoring, which is characterized in that the method is applied to as Claims 1-4 is any The serial ports shared system of the environmental monitoring, comprising steps of

Processing module divides each Industrial Control Computer and corresponding environment monitor session occupied serial ports time, obtains Multiple time slot t；And the priority level of setting Industrial Control Computer, to realize each Industrial Control Computer point of different priority levels It does not conversate in different time slots with corresponding environment monitor；

In each time slot, an Industrial Control Computer transmits network data to corresponding environment monitor, environmental monitoring by serial ports Instrument receives and responds the network data, and the network data is back to the Industrial Control Computer.

6. according to the method described in claim 5, it is characterized in that, time slot t=serial ports transmission data required time t₁+ string Mouth response waiting time t₂+ network latency t₃+ data processing time t₄+ serial ports returned data time t₅, wherein t₂≤50ms。

7. according to the method described in claim 6, it is characterized in that, if serial ports is in t₂Industrial Control Computer is responded in period, then will The network data is put into buffer area, and in t₃With t₄In period, the network data is back to corresponding environment monitor, The environment monitor receives and responds the network data, and the network data is back to the Industrial Control Computer, to terminate This time session simultaneously discharges serial ports, carries out session next time；If serial ports is not in t₂Industrial Control Computer is not responded in period, then directly Terminate this session, and discharge serial ports, carries out session next time.

8. according to the method described in claim 5, it is characterized in that, in one time slot, an Industrial Control Computer is being understood When words, the Industrial Control Computer not conversated sends network data to serial ports, which enters queue, successively waits next A slot transmission.

9. according to the method described in claim 8, it is characterized in that, the waiting of the Industrial Control Computer not conversated when Gap session queue maximum delay=mono- Time Slot Occupancy serial ports time * accesses the number of queues of this serial ports, wherein the time slot session Queue maximum delay≤1s.