CN208334996U - It can customize the embedded soft PLC control system of I/O port number - Google Patents

Abstract

The utility model provides a kind of embedded soft PLC control system that can customize I/O port number, it includes core board and peripheral board, wherein: the core board is can plug module, there is row's needle on the core board, it can be inserted in the corresponding socket of the peripheral board, externally provide the digital quantity of standard Transistor-Transistor Logic level to the peripheral board；With the hardware circuit module of optical coupling isolator, relay and a flexibly configurable input/output end port quantity on the peripheral board, the peripheral board also provides the socket of input/output module, if insertion is input module, then the port is input port, externally can connect external input device by binding post；If insertion is output module, which is output port, externally can connect output peripheral equipment by binding post.Control system according to the present utility model can improve flexibility with the quantity of flexible configuration input/output end port, avoid the occurrence of contact wasting phenomenon, maintainable strong.

Description

It can customize the embedded soft PLC control system of I/O port number

Technical field

The utility model relates to programmable logic controller (PLC) (PLC) technical field, in particular to one kind can customize the end I/O The embedded soft PLC control system of mouth quantity.

Background technique

Programmable logic controller (PLC) (Programmable Logic Controller, abbreviation PLC) be it is a kind of exclusively for The electronic device of digital operation applied and designed under industrial environment.All the time, because its reliable operation, programming are convenient Feature and can for industrial automation application provides safe and reliable, perfect solution and it is industrial automatic to be applied to for a long time Change control field.PLC is most common control equipment now, can almost complete all tasks of industrial control field.In work In industry control system, PLC completes complex process control, and the real time monitoring to production status frequently as main controller.With Supply side continuous development of the reform, the controller of the too busy to get away bottom that flourishes of intelligence manufacture, the use demand of PLC also will It is more and more, and also to its function, higher requirements are also raised.

The realization of PLC is divided into hard PLC and Soft- PLC.So-called hard PLC from the strict sense for be by hardware or one piece specially Asic chip realizes the execution of PLC instruction, that is, traditional PLC.And Soft- PLC be with some general CPU or MCU holds row come the explanation or compiling for realizing PLC instruction.PLC software (SoftPLC, also referred to as soft logic SoftLogic) is one Kind of the control system based on PC machine development structure, it have the function of hard PLC, reliability, speed, in terms of spy The Industrial PC of standard can be converted into Full Featured PLC process controller using software technology by point.PLC software combines meter The functions such as the digital output modul of calculation machine and PLC, Analog control, mathematical operation, numerical value processing, network communication, PID adjusting, lead to Multitask control kernel is crossed, powerful instruction set, quickly and accurately scan period, reliable operation are provided and can be connected Various I/O systems and network Open architecture.So PLC software provides function same as hard PLC, while mentioning again The various advantages of PC environment are supplied.

The beginning of this century, with computer and microelectric technique further development and associated control software gradually at Ripe, the bottleneck problem of SoftPLC technology is gradually resolved, and Soft- PLC has obtained further development.At the same time, embedded system System has obtained swift and violent development with its distinctive advantage.People combine SoftPLC technology with embedded system, produce embedding Enter formula SoftPLC technology.Embedded soft PLC is Soft- PLC of the framework in embedded system, has very extensive application prospect, Traditional hard PLC is replaced to have become a trend using the Soft- PLC based on embedded system in automatic field.However at present Embedded soft PLC both domestic and external is in the early stage of development, and mature product is few, therefore develops embedded soft PLC with important Meaning.

Fig. 1 is traditional PLC controller, i.e., hard PLC technology.It is one piece based on STM32F103ZET6 micro process such as Fig. 2 The Soft- PLC control module of the application-oriented layer insertion of device.PLC module software program can be developed, is made in the case where C language develops environment Obtain Embedded PLC module can complete basic FX2N function, i.e., complete PLC language in GX Developer exploitation environment and compile Journey then downloads on mainboard, completes the explanation instructed to PLC by STM32F103ZET6 and runs, and it is defeated externally to provide 64*64 The standard Transistor-Transistor Logic level for entering/exporting.That is SoftPLC technology.

However, there is also its disadvantages by existing PLC.PLC occur because of its closed framework expandability and flexibly The lower problem of property.The fixation of I/O (input/output) mouth number of traditional PLC just determines when factory, is by mark Quasi- I/O points design, for example, (20 points/20 points of input brilliant by 32MR PLC (16 points of/16 point relays of input output), 40MT-PLC The output of body pipe), 64MRPLC (32 points/32 point relays of input export) etc..User's later period can not voluntarily modify, and cannot reach and appoint Meaning cuts collocation；Although IO number can be extended by expansion module, resulting cost can also be risen with it.In practical work In journey project, it is frequently encountered actual needs I/O port quantity and the used unmatched situation of PLC controller IO quantity, is easy I/O port is caused to waste.Meanwhile once cause entire PLC to be unable to operate normally because of the failure of input/output end port, at this moment need Entire PLC controller is sent and is repaired, maintenanceability is poor, extremely inconvenient.

Utility model content

The shortcomings that the purpose of the utility model is to overcome the prior arts and deficiency, providing one kind can customize the port I/O The embedded soft PLC control system of quantity, user can according to actual items demand, the quantity of flexible configuration input/output end port, Flexibility is improved, contact wasting phenomenon is avoided the occurrence of.Meanwhile PLC controller used in the utility model is to pass through insertion Formula system research and development instead of traditional Soft- PLC controller module, once input/output module even core board module occur therefore Barrier, only needs to change the module of failure, repairs without will integrally send, improve maintenanceability.Quite there is practical significance.

The purpose of this utility model is achieved through the following technical solutions: a kind of to can customize the embedded of I/O port number Soft- PLC control system comprising core board and peripheral board, in which:

The core board be can plug module, have row's needle on the core board, the corresponding socket of the peripheral board can be inserted in On, the digital quantity of standard Transistor-Transistor Logic level is externally provided to the peripheral board；

There is optical coupling isolator, relay and a flexibly configurable input/output end port quantity on the peripheral board Hardware circuit module, the peripheral board also provides the socket of input/output module, should if insertion is input module Port is input port, externally can connect external input device by binding post；If insertion is output module, the port It is output port, externally can connects output peripheral equipment by binding post.

Further, when what is be inserted into is input module, the input module circuit receives opening for industrial field device Switching signal is converted to the acceptable signal of single-chip microcontroller by input isolation circuit by OFF signal, to allow PLC inside and outside signal Meet electrical isolation, wherein the isolation of input circuit is isolated using photoelectrical coupler TLP521-1.

Further, when what is be inserted into is output module, the Transistor-Transistor Logic level that the output module is provided according to core board, Via output interface module, the output signal after being boosted directly drives relay, wherein the output interface module uses Eight road NPN Darlingtons connect transistor array series ULN2803.

The utility model compared with the existing technology have following advantages and effects

A kind of embedded soft PLC control system can customize I/O port number provided by the utility model, has very high Flexibility and maintenanceability, compared with the fixation input/output end port number of traditional PLC controller, the utility model realize Flexible configuration input/output end port quantity.When causing to break down because of I/O unit, what directly can more be renewed is defeated Enter/output module, is repaired without whole send.

Also, the embedded soft PLC control system provided by the utility model that can customize I/O port number, control Main body is the embedded soft PLC controller researched and developed based on ARM microprocessor, and the controller used is microprocessor, Er Feishi Traditional PLC controller.In existing technology, plate is typically expanded plus IO with traditional PLC controller and carries out opening up for I/O port Exhibition.The core control panel researched and developed with embedded soft PLC technology cooperates input/output module circuit described in the utility model to set Meter has undoubtedly reached flexibility and the cost optimization of application.

Detailed description of the invention

Fig. 1 is PLC controller traditional in the prior art, i.e., hard PLC technology；

Fig. 2 is the Soft- PLC control module of the application-oriented layer insertion based on STM32F103ZET6 microprocessor；

Fig. 3 is the embedded soft PLC control system frame diagram that can customize I/O port number of the utility model；

Fig. 4 is the input module circuit diagram of the utility model；

Fig. 5 is ULN2803 schematic diagram used in the output module of the utility model；

Fig. 6 is the output module circuit diagram of the utility model.

Specific embodiment

The present invention will be further described in detail with reference to the embodiments and the accompanying drawings, but the implementation of the utility model Mode is without being limited thereto.

Embodiment one

As shown in figure 3, the utility model provides a kind of embedded soft PLC control system that can customize I/O port number System, range be suitable for it is any can external outputting standard Transistor-Transistor Logic level embedded software plc control panel.The control system includes core Core and peripheral board, in which:

The core board be can plug module, have row's needle on the core board, the corresponding socket of the peripheral board can be inserted in On, the digital quantity of standard Transistor-Transistor Logic level is externally provided to the peripheral board.Core board is the embedded software plc in existing research Control panel, so the realization of the utility model is in the hardware circuit design of peripheral board.Core board develops ring in high-level language Under border (such as C language), PLC module software program is developed, enables core board to complete basic traditional PLC function, such as in GX Developer exploitation environment is completed PLC language programming, is then downloaded on mainboard, is voluntarily completed by ARM microprocessor to PLC The explanation of instruction is run.Core board externally provides the digital quantity of standard Transistor-Transistor Logic level to peripheral board.

There is optical coupling isolator, relay and a flexibly configurable input/output end port quantity on the peripheral board Hardware circuit module, the peripheral board also provides the socket of input/output module, should if insertion is input module Port is input port, externally can connect external input device by binding post；If insertion is output module, the port It is output port, externally can connects output peripheral equipment by binding post.

In existing research, the bare board for using the conventional one-pieces such as 51 or STM32 machine as control chip is had already appeared Embedded software plc control panel also occurs that the embedded software plc control panel of operating system can be run.These control panels are above " core board ".How to realize that the explanation to PLC language is run as core board, software code, hardware circuit do not exist This patent scope is briefly described at this, it is only necessary to know that these embedded softwares plc control panel can explain PLC language Operation, and the digital quantity of the Transistor-Transistor Logic level of standard is externally provided, for user's designed, designed external circuit.Continue emphatically peripheral board below The external hardware circuit design of arbitrary disposition input/output end port quantity is realized based on the Transistor-Transistor Logic level that core board provides.

As shown in Fig. 2, being the Soft- PLC control of one piece of application-oriented layer insertion based on STM32F103ZET6 microprocessor Module.Serial ports 422 can be used to communicate as traditional PLC, by the serial ports, PLC language can be downloaded to core board by PC machine, Core board can voluntarily analyze operation code, and externally provide the Transistor-Transistor Logic level of 64*64 as shown in the figure.

Fig. 3 is the embedded soft PLC control system frame diagram that can customize I/O port number of the utility model, because drawing Figure is convenient, only draws 8 road input/output modules.Certainly it is directed to different core boards, it is designed by the different demands of user Peripheral board is not necessarily identical.Wherein, the embedded soft PLC core control panel module based on ARM microprocessor can be inserted in peripheral board Centre, just as core control panel shown in Fig. 2 is just inserted among peripheral board on corresponding insert row, and to peripheral board provide input/ The digital quantity of the Transistor-Transistor Logic level of output, peripheral board provide DC voltage by power supply adaptor, are converted to operating voltage and are supplied to core Plate.It might as well be set as the operating voltage of ± 24V supply voltage He ± 5V herein.Either core board or input/output circuitry, All be designed to can plug module.Such as Fig. 2, there is row's needle on core board, can be inserted in the corresponding socket of peripheral board.Periphery simultaneously Plate also provides the socket of input/output module, as shown in figure 3, respective modules can be inserted into according to selection, if insertion is input Module, then the port is input port, externally can connect external input device, such as control switch by binding post；If inserted What is entered is output module, then the port is output port, externally can connect output peripheral equipment, such as motor by binding post.

Further, when what is be inserted into is input module, the input module circuit receives opening for industrial field device Switching signal is converted to the acceptable signal of single-chip microcontroller by input isolation circuit by OFF signal, to allow PLC inside and outside signal Meet electrical isolation, wherein the isolation of input circuit is isolated using photoelectrical coupler TLP521-1.

PLC has various Anti-interference Designs in input circuit part to improve the anti-interference ability of system.The design's is defeated Enter circuit and also copy PLC, is separated input power and system power supply using photoelectric coupling before signal is input to single-chip microcontroller.Below Input isolation circuit all the way is only introduced, remaining each road input isolation circuit is similar.

The switching signal that input circuit receives industrial field device converts a signal into monolithic by input isolation circuit The acceptable signal of machine, to allow PLC, inside and outside signal meets electrical isolation.The input signal of the design selects direct current input side Formula, design guarantees when signal is true electric current 5 to 7mA in text.In view of the interference free performance of control circuit, input circuit every It is isolated from using TLP521-1.

As shown in figure 4, P2 is an input terminal of PLC, a binding post can be connected to and conveniently connect with external equipment.D1 It is used to indicate the switch state of the input point.It is separated between input signal and single-chip microcontroller with U1 photoelectrical coupler TLP521-1.R1 It is current-limiting resistance.Estimate input current about are as follows: the primary side driving current of (24-2)/4.7=4.7mA, photoelectrical coupler are general In 4.5mA or more, meet design requirement.The input pin of IN1 connection single-chip microcontroller.Assuming that P2 is connected to a control switch, such as Fruit closes the switch, and the circuit conducting where the light emitting diode of U1, then another way will also be connected, and IN1 is high level, and is passed to Core board informs the conducting of the core board input port, meanwhile, D1 shines, and indicates that the input point has been turned on.

Further, when what is be inserted into is output module, the Transistor-Transistor Logic level that the output module is provided according to core board, Via output interface module, the output signal after being boosted directly drives relay, wherein the output interface module uses Eight road NPN Darlingtons connect transistor array series ULN2803.

If Fig. 5, ULN2803 are eight road NPN Darlingtons connection transistor array series, especially suitable for low logic level number Circuit (such as TTL, CMOS or PMOS/NMOS) and higher current/voltage require between interface, can be used to directly drive after Electric appliance.Core board provide the end Transistor-Transistor Logic level O0-O7 boosted after ULN2803 after OUT0-OUT7, can directly drive Motor type relay.

The output circuit of the utility model is the relay way of output, can drive DC load, the voltage swing used Wider range, while the ability of bear to take advantage of a situation overvoltage and overcurrent is stronger.The rated current of PLC external equipment should be less than defeated The output current driving ability of circuit out, it is therefore desirable to the output electric current of output circuit is determined according to actually.

As shown in fig. 6, P5 is an output end of PLC, a binding post can be connected to and conveniently connect with external equipment, it is right External drive equipment, such as motor etc. can be connect outside.It is directly connected to via the OUT0 for directly driving relay that ULN2803 is obtained Relay, when it is conducting that OUT0, which is arranged, to correspond to pin, OUT0 is low level, and long switch K1 closure, the both ends P5 are also switched on, just Controllable external equipment, while D2 indicator light is bright, indicates that the output point has been turned on.

As it can be seen that a kind of embedded soft PLC control system that can customize I/O port number provided by the utility model, has Very high flexibility and maintenanceability, compared with the fixation input/output end port number of traditional PLC controller, this is practical new The quantity of type flexibly configurable input/output end port, flexibility are high.Also, traditional PLC controller a part breaks down, Entire controller is needed to send to maintenance, the utility model is integrally built using modularization idea, either core board module, or It is input/output module, once module breaks down, only needs to change corresponding module, other hardware is all not required to change, maintainable By force.

Embodiment two

A kind of embedded soft PLC control system can customize I/O port number of the utility model can be by such as dividing into Meter is realized: input/output module being respectively designed to two pieces of circuit boards, has row's needle on the circuit board, corresponds on peripheral board The socket in face, row's needle on the input/output module are inserted in the socket of respective needle mouth, are mentioned for the input/output module For all kinds of voltages and and input/output Transistor-Transistor Logic level.It in this way can the corresponding input/output module of plug as needed.

Further, the input/output module is respectively provided with 6 needles row's needle and 2 needles row's needle, wherein described 6 The operating voltage signal that needle row's needle is separately connected power supply voltage signal, is supplied to core board, and the input corresponding to core board Transistor-Transistor Logic level signal and output Transistor-Transistor Logic level signal；The 2 needle row needle is connected to external equipment by binding post.

By above to the analysis of input/output circuitry, it can be found that the unified point of one of the two.Both there is one 6 Needle arranges needle and 2 needles arrange needle.Wherein, supply voltage has been connect for 6 pins of 6 needles row's needle respectively and has been supplied to core The operating voltage of plate, might as well be set as the supply voltage of ± 24V and the operating voltage of ± 5V herein and one corresponds to core The input Transistor-Transistor Logic level signal of plate and an output Transistor-Transistor Logic level signal, this 6 signals are for using any ARM microprocessor as master The core control panel for controlling chip, is the same, and requires a pair of outer supply voltage, and convert by voltage conversion chip For operating voltage required for core board, generally ± 5V or ± 3.3V, meanwhile, no matter for input or output circuit It is consistent.So the socket of 6 needles can be designed on peripheral board, and above 6 signals are connected, on input/output module Corresponding 6 needle row's needle can be inserted in this 6 needle socket, and all kinds of voltages and and defeated can be so provided to input/output module Enter/export Transistor-Transistor Logic level.

Needle is arranged for 2 needles on input/output module, in input circuit module, in conjunction with Fig. 3 and according to before to input One of 2 needles row's needle known to the analysis of circuit at this time is terminated with -24V, and-the 24V that can be arranged on needle by 6 needles is provided, while this both ends Pass through the external input equipment of binding post.Equally, in output circuit module, it is external that the both ends of 2 needles row's needle directly pass through binding post Output peripheral equipment.That is this 2 needle arranges needle not by peripheral board, is not influenced by core board, directly by the input/output mould Circuit above block determines function.

Therefore, for input/output module, 6 needles arrange needle can be provided 6 unified needle sockets by peripheral board, and each 6 needle is arranged It inserts and is all connected to same voltage signal and corresponding input/output Transistor-Transistor Logic level, 2 needles row's needle is mentioned without core board or peripheral board For any signal, only needs peripheral board to provide a 2 needle sockets and facilitate input/output module plug, while this 2 needle socket can connect It is connected on a binding post, facilitates the connection of input/output end port and external equipment.

It is above exactly the basic introduction of the circuit design principle.

Embodiment three

The design of peripheral circuit plate can be it is rich and varied, in order to which the flexible configuration for cooperating the utility model to be introduced is defeated Enter/the control system of output port quantity, is tested herein just for the basic input/output function of embedded soft PLC module Card, future can add more functions, such as increase other function interface, expand voltage and current range etc..This example uses made The embedded software plc control panel based on STM32F103ZET6 made, as shown in Fig. 2, shared 64*64 input/output TTL electricity Straight cut, so totally 64 input/output sockets can be designed in peripheral board.

The case where common input port quantity of simulation actual items engineering is much larger than output port number now, does 9 groups of tests, Every group takes 5 input port X1-X5, and 2 output ports Y1, Y2.Wherein 5 input ports be connected to 5 switch, 2 Output port connects 2 motors.So needing 45 * 18 output interfaces of input.Can be realized by following steps can customize I/O The embedded soft PLC control system of port number:

The first step builds embedded soft PLC platform.

1) it is needed to select embedded software plc control panel according to project.Here select team production based on The embedded software plc control panel of STM32F103ZET6, can externally provide 64*64 input/output Transistor-Transistor Logic level, and certainly following is embedding Entering control chip used by formula plc control panel has very big development potentiality, and more advanced chip can be used and realize longitudinal mention It rises.

2) peripheral board has been designed and produced with the utility model.For convenience of test, peripheral circuit plate only includes external electrical The insert row of source interface, power-switching circuit and core board and input/output module, rough lithograph as shown in figure 3, In follow-up study, more functions will be increased, such as increase voltage and current.

3) 45 pieces of input modules and 18 pieces of output modules are ready to according to test demand.According to Fig. 4, Fig. 6 production input/it is defeated Module board out.

4) equipment is built.As shown in figure 3, core board is inserted in peripheral board central location, by 45 pieces of input modules and 18 pieces Output module is arbitrarily inserted in input/output socket, but connection external equipment or every group is placed simultaneously for convenience.And External equipment is connected on the corresponding binding post of input/output, has 5 switches and 2 motors for every group herein.

Second step compiles programming code according to the hardware platform put up, and the code enables to the external equipment Execute operating.

At this point it is possible to complete PLC language programming in PLC exploitation environment (the GX Developer of such as Mitsubishi) according to demand. Wherein 1 group of test is explained below, other 8 groups are just as.The purpose of program is positive and negative by motor Y1 difference after lower switch X1, X2 Turn, distinguishes positive and negative rotation by motor Y2 after lower switch X3, X4, press two motors of X5 and stop operating.After compiled program, to outer Coaming plate is connected with the mains, can will be on program burn writing to core board by 422 serial ports (simulation practical PLC communication).

Third step, equipment debugging can customize I/O port number by observing motor working order by lower switch to realize The debugging of the embedded soft PLC control system of amount.

By above embodiment, it is convenient that the utility model bring more intuitive can be realized.For above 45 * 18 output of input, if using traditional PLC controller, if will be unable to full using 64 points of PLC (32*32 input/output) 45 input ports that this test of foot needs.If using 128 points (64*64 input/output), it will cause contact to waste, improve Cost.

Example IV

Another embodiment that can reach same effect is introduced with most common 51 single-chip microcontroller again below.It is intended to illustrate Utility model be applicable in it is any can external outputting standard Transistor-Transistor Logic level embedded software plc control panel.

In order to facilitate introduction, only make battery of tests here, only take 5 input port X1-X5 and 2 output port Y1, Y2.Wherein 5 input ports are connected to 5 switches, and 2 output ports connect 2 motors.

The first step builds embedded soft PLC platform.

1) it is needed to select embedded software plc control panel according to project.The most common single-chip microcontroller is specifically selected, i.e., based on tradition The embedded software plc control panel of 51 single-chip microcontrollers, can externally provide 8*8 input/output Transistor-Transistor Logic level.

2) peripheral board is made with thinking described in the utility model.For convenience of test, peripheral circuit plate equally only includes The insert row of external power interface, power-switching circuit and core board and input/output module, rough lithograph such as Fig. 3 institute Show.

3) 5 pieces of input modules and 2 pieces of output modules are ready to according to test demand.Input/output is made according to Fig. 4, Fig. 6 Module board.

4) equipment is built.As shown in figure 3, core board is inserted in peripheral board central location, 5 pieces of input modules and 2 pieces are defeated Module is arbitrarily inserted in input/output socket out, but connection external equipment for convenience, and every group is placed simultaneously.And input/ It exports and connects external equipment on corresponding binding post, there is 5 switches and 2 motors herein.

Second step compiles programming code according to the hardware platform put up, and the code enables to the external equipment Execute operating.

At this point it is possible to directly adopt C language according to purpose and write the program that can reach purpose, do not need to realize to PLC's Interpretive analysis.After compiled program, connect with the mains to peripheral board, it can be by jtag interface by program burn writing to 51 single-chip microcontrollers On.

Third step, equipment debugging can customize I/O port number by observing motor working order by lower switch to realize The debugging of the embedded soft PLC control system of amount.

To sum up, can verify the circuit designing thought that the utility model is introduced be applicable in it is any can external outputting standard TTL The embedded software plc control panel of level.Either rudimentary microprocessor or advanced processor, either directly adopt C Language directly writes control program or realizes the interpretive analysis to PLC language, as long as core control panel can finally provide mark Quasi- Transistor-Transistor Logic level can all use the control system of the utility model.

As it can be seen that a kind of embedded soft PLC control system that can customize I/O port number provided by the utility model, has Very high flexibility and maintenanceability, compared with the fixation input/output end port number of traditional PLC controller, this is practical new Type realizes flexible configuration input/output end port quantity.When causing to break down because of I/O unit, can directly replace New input/output module is repaired without whole send.

Also, the control main body of the utility model is the embedded soft PLC controller researched and developed based on ARM microprocessor, The controller used is microprocessor, rather than is traditional PLC controller.In existing technology, typically with traditional PLC control Device processed expands the expansion that plate carries out I/O port plus IO.It is originally practical with the core control panel cooperation that embedded soft PLC technology is researched and developed The novel input/output module circuit design has undoubtedly reached flexibility and the cost optimization of application.

Above-described embodiment is the preferable embodiment of the utility model, but the embodiments of the present invention is not by above-mentioned The limitation of embodiment, it is made under other any spiritual essence and principles without departing from the utility model to change, modify, replacing In generation, simplifies combination, should be equivalent substitute mode, is included within the protection scope of the utility model.

Claims (3)

1. a kind of embedded soft PLC control system that can customize I/O port number, which is characterized in that including core board and outside Coaming plate, in which:

The core board be can plug module, have row's needle on the core board, can be inserted in the corresponding socket of the peripheral board, The digital quantity of standard Transistor-Transistor Logic level is externally provided to the peripheral board；

With the hard of optical coupling isolator, relay and flexibly configurable input/output end port quantity on the peripheral board Part circuit module, the peripheral board also provide the socket of input/output module, if insertion is input module, the port It is input port, externally can connects external input device by binding post；If insertion is output module, which is defeated Exit port externally can connect output peripheral equipment by binding post.

2. a kind of embedded soft PLC control system that can customize I/O port number as described in claim 1, feature exist In when what is be inserted into is input module, the input module circuit receives the switching signal of industrial field device, passes through input Switching signal is converted to the acceptable signal of single-chip microcontroller by isolation circuit, to allow PLC, inside and outside signal meets electrical isolation, The isolation of middle input circuit is isolated using photoelectrical coupler TLP521-1.

3. a kind of embedded soft PLC control system that can customize I/O port number as described in claim 1, feature exist In, when what is be inserted into is output module, the Transistor-Transistor Logic level that the output module is provided according to core board, via output interface mould Block, the output signal after being boosted directly drive relay, wherein the output interface module is connected using eight road NPN Darlingtons Meet transistor array series ULN2803.