CN100538567C

CN100538567C - Programmable Logic Controller

Info

Publication number: CN100538567C
Application number: CNB2007101811441A
Authority: CN
Inventors: 桶田英男; 中西英治
Original assignee: Omron Corp
Current assignee: Omron Corp
Priority date: 2006-10-12
Filing date: 2007-10-12
Publication date: 2009-09-09
Anticipated expiration: 2027-10-12
Also published as: CN101162391A; JP4788912B2; TWI347555B; TW200825911A; KR100932057B1; JP2008097369A; KR20080033861A

Abstract

A kind of Programmable Logic Controller is provided, can carries out the online loading and unloading of no instrument of unit, and can alleviate the processing burden that the unit is broken away from the system program side when judging.In CPU element (2) by certain a connector (13a～when detecting exception response when 13d) having visited functional unit, the memory contents of the internal register (12) of relevant this connector of reference, when simultaneously being judged as " unit disengaged position ", carry out processing required when dismantling in the unit in this memory contents.

Description

Programmable Logic Controller

Technical field

The present invention relates to need not tool using (tool), also can realize the Programmable Logic Controller (below, be called PLC) of the online loading and unloading of unit.

Background technology

So far, known CPU element and a plurality of functional unit are connected to each other by the I/O bus, and each PLC that can install, dismantle for the I/O bus by connector of each functional unit.

Here, as functional unit, for example can enumerate I/O unit (general name IN unit, OUT unit and IN, OUT mixed cell), communication unit (communication unit between general name PLC, master/slave communication unit and go up communication unit between bed device), special function unit (thermostat unit, PID control module, action control unit, position control unit etc.) etc.

In this PLC, arrive each functional unit via the I/O bus access as required by CPU element, thereby realize the function of relevant this functional unit.That is,, then visit this I/O unit, thereby can realize reading from the function of the input signal of outside or the outside is transmitted the function of output signal by CPU element if functional unit is the I/O unit.In addition,, then visit this communication unit, thereby can realize function such as communication function between communication function between PLC, long-range substation by CPU element if functional unit is a communication unit.And, if functional unit is a special function unit, then visit this special function unit by CPU, thus can realize respectively this special function unit intrinsic function (temp regulating function, pid control function, moving control function, position control function etc.).

In CPU element, microprocessor and storer are installed.Microprocessor is by moving according to the system program of being read from the system program zone of storer, and common processing, user program are carried out and handled, I/O upgrades and handles and peripheral service processing thereby repeat.

In common the processing, carry out the various hardware checks of check etc. of user program storage area of check, the storer of battery abnormal test, I/O bus.Carry out in the processing at user program, from the user program storage area of storer, read the various instruction words that constitute user program successively, while is with reference to the I/O data execution command word of the I/O data area of storer, according to this execution result, rewrite the processing of content of the I/O data area (particularly, OUT data area) of storer.During I/O upgrades and handles, the I/O data area of carrying out the IN writing data into memory that will be read by the I/O unit (particularly, writing processing (IN upgrades processing) and will be sent to the processing (OUT upgrades processing) of the I/O unit IN data area) from I/O data area (particularly, OUT data area) the OUT data of reading of storer.

In addition, for the user program that will regenerate or edit uploads to storer in the CPU element, perhaps from same storer download user program, perhaps will be used to carry out the setting data zone of setting data write store of the various function settings of PLC, perhaps revise, use the instrument of regulation.This instrument generally is to realize by the application program be used to realize as the function of instrument is installed in personal computer, and is connected with PLC by cable.

But, in comprising the PLC that this a plurality of functional unit constitutes, in order to exchange the functional unit of fault, perhaps for the maintenance function unit, wish to make input-output unit or functional units such as communication unit or special function unit, former state continues the operation of PLC, dismantle simultaneously, install (below, be called " the online loading and unloading of unit ").

In the system program of being stored in the storer in CPU element, when being installed, handles the communication abnormality of regulation.Handle constituting during this communication abnormality, when for the visit of some unit the time, detecting exception response, the operation of PLC is forcibly stopped (below, be called " system failure ").

In the past, adopt following method: continue the operation of PLC for former state, simultaneously can carry out the disassembling function unit about specified connector, change the setting data in the storer of CPU element by the instrument that is connected to PLC via cable, thereby required processing when carrying out removable unit, on the other hand, continue the operation of PLC for former state, simultaneously can carry out the installation function unit about specified connector, change the setting data in the storer of CPU element by the instrument that is connected to PLC via cable, thus required processing when carrying out installation unit.

Wherein, be for example, when this unit of visit, to produce exception response as " during removable unit required processing " even can enumerate, can starting system fault function yet, simultaneously, afterwards, about having dismantled the connector of this unit, do not accept signal from the outside without exception, and then, about this connector, CPU element processing such as do not conduct interviews afterwards.On the other hand, as " during installation unit required processing " is for example, can enumerate by tool operation to come the change setting data and return original state, thereby can accept signal, restart processing such as visit simultaneously for this unit from this connector.

But, by using such instrument can carry out in the previous methods of online loading and unloading of unit, when carrying out the online loading and unloading of unit at every turn, in workshop that PLC is fixed etc., must bring the personal computer that has as the effect of instrument, so operability and maneuverability worsen at every turn, in addition, the appointment that should carry out the connector of unit loading and unloading is the tool operation of delegate user, so if connector is specified on user error ground, might cause the system failure.

Therefore, in order to solve such problem, so far, the known tool using (no instrument) that need not, the PLC (with reference to patent documentation 1) that can carry out the online loading and unloading of unit.

In the PLC of the online loading and unloading of no instrument of such carried out unit, each side at the functional unit that becomes the loading and unloading object, be provided with the installation in the unit, the switch of action when dismantling, in the CPU element side, be provided with status register, this status register has being connected by dedicated signal lines each with above-mentioned each switch, is used to store the storage area by each connector by the switching signal that action produced of each switch simultaneously.As other example, the switching signal by above-mentioned applies interruption to microprocessor, and by Interrupt Process to status register write switch signal.

Promptly, this status register has the storage area by each connector, interlock is in carrying out the disassembling section of functional unit about some connectors simultaneously, in the storage area of relevant this connector, be stored first state (state that the unit is disassembled), and interlock is stored second state (state that the unit is mounted) in the fitting operation that carries out functional unit about some connectors in the storage area of relevant this connector.

On the other hand, the system program side of being stored in the storer in CPU element, following function is installed: become in visit before each unit of loading and unloading object, content with reference to above-mentioned status register, while is as the result of this reference, in the variation (unit disengaging) that is judged to be from the state variation of installing to the state of dismounting, when perhaps being judged to be variation (unit installation), carry out the online loading and unloading of each unit required " during removable unit required processing " or " during installation unit required processing " from the state variation of dismounting to the state of installing.

According to such structure, if when carrying out the disassembling section of unit or fitting operation, based on the variation of the memory contents of status register, the required processing of online loading and unloading of performance element automatically, so even tool using does not come the operating and setting data, also can carry out the online loading and unloading of unit.

Patent documentation 1: the spy opens flat 5-241622 communique

But, in the PLC of the online loading and unloading of no instrument of such carried out unit, owing to only rely on the variation of the memory contents of status register, the variation (unit disengaging) of the state of identifying unit from the state that is mounted to dismounting, so judge exactly that in order not omit ground the unit of each unit that becomes the loading and unloading object breaks away from, so when visiting each unit by connector at every turn, before it, must be at every turn to bear great problem points so produce the processing of system program side with reference to content corresponding to the status register of this connector.That is, that be because, if status register has been left in the basket with reference to one-period, lets slip the unit and break away from the connector that the accessing unit is disassembled, then in response to the generation of exception response, the system failure is handled and is started.

Summary of the invention

The present invention is conceived to such problem points in the past and finishes, and its purpose is, a kind of Programmable Logic Controller is provided, and can carry out the online loading and unloading of no instrument of unit, and can alleviate the processing burden of the system program side when identifying unit breaks away from.

If those skilled in the art by the record of reference the following description book, can be readily appreciated that other purposes of the present invention and action effect.

Above-mentioned problem can realize by the PLC with following structure.Promptly, this PLC constitutes, CPU element and a plurality of functional unit are connected to each other by the I/O bus, and each of each functional unit can install, dismantle by connector the I/O bus, and, visit each functional unit by the I/O bus as required by CPU element, thereby realize the function of relevant this functional unit.

Also comprise status register, first control assembly and second control assembly among the above-mentioned PLC.

Status register constitutes, and has the storage area by each connector, and interlock is stored first state in carrying out the disassembling section of functional unit about some connectors in the storage area of relevant this connector simultaneously; And interlock is stored second state in the fitting operation that carries out functional unit about some connectors in the storage area of relevant this connector.

First control assembly, when when CPU element has access to functional unit by some connectors, detecting exception response, the memory contents of the status register of relevant this connector of reference when this memory contents is judged as first state, continues the operation of PLC simultaneously for former state, simultaneously about specified connector, can the disassembling function unit, carry out processing required when removable unit, on the other hand, when being judged to be second state, handle during the communication abnormality that puts rules into practice.

Second control assembly, in the memory contents that is judged to be status register about some connectors when first state variation is second state, for former state continues the operation of PLC, simultaneously about specified connector, can the installation function unit, carry out processing required when installation unit.

According to such structure, continue the operation of PLC for former state, simultaneously can carry out the required processing of dismounting (the online disengaging of unit) of functional unit about specified connector, only be detected exception response during the access function unit by some connectors in CPU element, and when being judged as first state, the memory contents of the status register of relevant this connector carries out, so only be detected in the unit exception response as the visit as a result the time, generation is with reference to the needs of status register, with visit each functional unit in CPU element at every turn before need to compare the processing of mitigation system program side burden significantly with reference to the example in the past of status register.On the other hand, when having access to some functional units, when having produced real communication abnormality with the unusual grade of I/O bus and being the exception response of reason, the memory contents of status register is represented second state, normally carried out so handle during communication abnormality, to carry out necessity of the system failure etc. and handle.

In addition, continue the operation of PLC for former state, simultaneously can carry out the required processing of installation (the online installation of unit) of functional unit, carry out during from first state variation to second state in the memory contents that is judged as status register about some connectors about specified connector.Begin for the action after the installation end of relevant this unit, allow some time delays.Because only to by the unit of online disengaging, monitor to be got final product by the situation of online installation, the processing of system program side burden can not become problem.

In such PLC, second control assembly also can constitute, based on by connector from the unit identification information that functional unit read, be judged to be before and after the elements exchange in unit when inconsistent, required processing when performance element is not installed.

According to such structure, during online crosspoint, installed mistakenly under the situation of unit of other kinds, can not begin the operation of relevant this unit again, take precautions against in possible trouble so the unit of the kind of mistake suddenly can be participated in the eventuality attitude that is produced.

In addition, in above-mentioned PLC, also can also comprise: judging part, in the content that is judged to be status register about some connectors when first state variation is second state, based on by this connector from the unit identification information that functional unit read, judge to have or not the error unit exchange; And the marking of control parts, with the result of determination of judging part, be reflected as can be by PLC user program or the display routine of programable display come reference one or two more than the state of elements exchange error flag.

According to such structure, if the generation unit exchange is mistaken, specific markers can be set to the logical value stipulated immediately, if so in advance this mark is weaved into the user program that display lamp is lighted as initial conditions, perhaps this mark is weaved into the display routine of programable display as initial conditions, even then there are not other instruments, also can notify the user immediately with the mistaken situation about being produced of elements exchange.

At this moment, in the elements exchange error flag more than the display routine of user program that can be by PLC or programable display comes one or two of reference, comprise the mark of the situation of failing in the online exchange of expression.

According to such structure, if in advance this mark is weaved into the user program of lighting as display lamp as initial conditions, perhaps this mark is weaved into the display routine of programable display as initial conditions, even then there are not other instruments, in any case also can pass through display lamp or programable display, notify the user because of the situation of certain reason at the online swap fault of unit.

In addition, in the elements exchange error flag more than the display routine of user program that can be by PLC or programable display comes one or two of reference, comprise the mark of situation that the kind of functional unit has been made a mistake in expression.

According to such structure, if in advance this mark is weaved into the user program of lighting as display lamp as initial conditions, perhaps this mark is weaved into the display routine of programable display as initial conditions, even then there are not other instruments, also can pass through display lamp or programable display, reset into when original in unit that will dismounting, with the advisory user the who mistakenly unit of other kinds is restored.In addition, such mark as initial conditions, is weaved into the user program of the countermeasure processing that is equivalent to when elements exchange is mistaken, then can take suitable countermeasure corresponding to mistaken kind.

In addition, in the elements exchange error flag more than the display routine of user program that can be by PLC or programable display comes one or two of reference, comprise the mark of situation of setting that a setting item of relevant cell side has been made a mistake in expression.

According to such structure, if in advance this mark is weaved into the user program of lighting as display lamp as initial conditions, perhaps this mark is weaved into the display routine of programable display as initial conditions, even then there are not other instruments, also can pass through display lamp or programable display, reset into when original in unit that will dismounting, with mistakenly the mistaken advisory user of the setting of a setting item of relevant cell side.In addition, such mark as initial conditions, is weaved into the user program of the countermeasure processing that is equivalent to when elements exchange is mistaken, then can take suitable countermeasure corresponding to mistaken kind.

According to the present invention, a kind of Programmable Logic Controller is provided, the online loading and unloading of no instrument of unit can be carried out, and the processing burden of the system program side when identifying unit breaks away from can be alleviated.

Description of drawings

Fig. 1 is the structural drawing of the base unit of PLC.

Fig. 2 is the memory content table of the data configuration in the expression CPU element.

Fig. 3 is the process flow diagram of the entire process of expression CPU element.

Fig. 4 is the detail flowchart when importing exception response from the unit.

The detail flowchart that Fig. 5 handles when being the unit installation.

Fig. 6 is Action Specification figure of the present invention.

Label declaration

1 base unit

Installation region, 1a CPU unit

The various functional units of 1b installation region

2 CPU element

3 I/O unit

4 communication units

5 special function units

6 programable displays

The 11I/O bus

12 internal registers

13a, 13b, 13c, 13d connector

14 signal wires

21?CPU

22 storeies

M1 system storage zone

M2 working storage zone

M3 user program memory zone

M4 default memory area

M5 I/O data area

The online swap status memory area of M6

The online swap fault mark of M610

M620 unit kind error flag

M631～M63N cell side is set error flag and (is set 1～N)

Embodiment

Below, the PLC that present invention will be described in detail with reference to the accompanying is preferred embodiment.

Fig. 1 represents the structural drawing of the unit, basis (base) of PLC.As shown in Figure 1, this base unit 1 is the elongated rectangular plate-shaped member that is also referred to as base plate (back plane) or mother board etc., and its surface has defined CPU element installation region 1a and has been used for the installation region 1b of a plurality of functional units.

Here, as the various functional units outside the CPU element, as known to persons skilled in the art, can enumerate I/O unit (general name IN unit, OUT unit and IN, OUT mixed cell), communication unit (between general name PLC communication unit, master/slave communication unit and go up communication unit between bed device), special function unit (thermostat unit, PID control module, action control unit, position control unit etc.) etc.

Dispose the connector (not shown) that is used to install CPU element among the 1a of CPU element installation region, a row ground disposes a plurality of (is 4 in the illustrated embodiment) connector 13a～13d that is used for installing these functional units in various functional units installation region 1b simultaneously, and these connectors 13a～13d connects by the I/O bus of being laid on the base unit 1 (the various control signal wires that comprise address signal line, data signal line) 11.Therefore, CPU element and can carry out the exchange of data by I/O bus 11 at the various functional units that connector 13a～13d is installed.

Built-inly in each of each connector 13a～13d connect the power switch (not shown) that disconnects by control signal Be Controlled from CPU element, by being connected, this power switch disconnects, thus the energising that can connect the unit that disconnection installs for each connector.In addition, in each connector 13a～13d, the unit detection part (not shown) that built-in interlock is connected disconnection in the fitting operation or the disassembling section of functional unit, connect by this unit detection part and to disconnect, can detect in this connector installation function unit, from the situation of this connector disassembling function unit.As an example of unit detection part, can be when being installed in connector by functional unit, the structure of signal wire conducting between functional unit and connector, thus have the structure of switching function.That is, when functional unit was installed in connector, when signal wire conducting and switch connection, functional unit became disengaged position from this state, signal wire was cut off and switch disconnects.Also can by signal wire 14a～14d, be sent to internal register 12 with the state of this switch as detection signal.

Among the installation region 1b of the various functional units on base unit 1, be provided with the internal register (being equivalent to status register of the present invention) 12 that has with each corresponding a plurality of isolated memory areas territory of each connector 13a～13d.In addition, this internal register 12 also can be arranged on CPU element installation region 1a, and, also can be built in the CPU element (not shown) that is installed in CPU element installation region 1a.

Each isolated memory area territory of internal register 12 is connected to connector 13a～13d by the dedicated signal line 14a～14d that is different from I/O bus 11.The detection signal that is built in the unit detection part of each connector 13a～13d is sent to internal register 12 by signal wire 14a～14d.Its result, interlock is in carrying out the disassembling section of functional unit about some connector 13a～13d, (for example automatically be stored first state in the isolated memory area territory of relevant this connector in internal register 12, " 1 "), and interlock is in the fitting operation that carries out functional unit about some connectors, automatically be stored second state (for example, " 0 ") in the isolated memory area territory of relevant this connector in internal register 12.Thus, in each isolated memory area territory of internal register 12, become all the time the data of loading and unloading state (state that the unit is mounted or the state that is loaded and unloaded) that storage is used to represent the unit of each connector at every moment.

Internal register 12 is also connected to I/O bus 11.Therefore, can read the memory contents in each isolated memory area territory of internal storage 12 from CPU element by the I/O bus.Thus, CPU element is passed through the memory contents of I/O bus 11 with reference to the isolated memory area territory of internal register 12, thereby can confirm the unit loading and unloading state of each connector.

In addition, in the drawings, CPU21 is the operation processing unit (comprising microprocessor or ASIC) that is built in CPU element.In addition, storer 22 is to concentrate expression to be included in the system storage, work (work) storer, user program memory, default storer, I/O data-carrier store, online swap status storer etc. of CPU element.

Then, CPU element is described.Fig. 2 represents to be built in the memory content table (memory map) of the distribution of the address space that the microprocessor of CPU element manages.

As illustrated in fig. 2, in the address space, system storage zone M1, working storage zone M2, user program memory zone M3, default memory area M4, I/O data area M5 and online swap status memory area M6 have been assigned with.

System storage zone M1 is, the microprocessor that constitutes CPU21 is used to realize zone as required various system programs (firmware) storage of the function of PLC.

Working storage zone M2 is, as the employed zone, various perform regions that is used to store intermediate results of operations etc. when the same microprocessor executive system routine.

User program memory zone M3 is, is used to store the user and utilized the control program suitably weaved into behind the trapezoid figure language, be used to realize the control function expected, has been the zone of user program.

Default memory area M4 is, when being used to be stored in executive system routine the zone of the required default information of the setting, selection etc. of pre-prepd variety of option.

I/O data area M5 is, is used to store the zone of the state of user's the various external input devices that the controlling object system comprised (pushbutton switch, limit switch, microswitch etc.), state of various output peripheral equipment (relay, various drivers etc.) etc.The operand that the data of this I/O data area M5 can be used as employed each order of user (LD order, IN order, OUT order, AND order and OR order etc.) uses.In other words, the storage data of this I/O data area M5 can suitably be referenced at user program.

Online swap status memory area M6 is newly-installed related to the present inventionly zone.In this online swap status memory area M6, shown in expansion among the figure, comprising: online swap fault mark M610, unit kind error flag 620, cell side are set error flag (setting 1)～(setting N) 631～63N.

Online swap fault mark M610 is during because of certain former thereby online elements exchange (former state continues the operation of PLC, dismantles a certain functional unit simultaneously, afterwards the situation of An Zhuaning) failure, to be set to the mark of " 1 " from " 0 ".As described later, as the reason of online elements exchange failure, exist the kind of having made a mistake the unit situation, made a mistake a variety of causes such as situation that cell side is set.

Unit kind error flag M620 is, during online elements exchange, for example, the OUT unit should be installed, and the situation that the IN unit but has been installed mistakenly is the same, and the kind of unit when mistaken, is set to the mark of " 1 " from " 0 ".

(setting 1～N) error flag M631～M63N is in the cell side setting, because of certain reason when the elements exchange, the setting of having made a mistake cell side (for example, under the situation of communication unit, set 1=node number (in the information of determining on the network as the PLC of node), set 2=unit number (information of determining unit on PLC) etc.) time, (1～N) is set to the mark of " 1 " relatively from " 0 " with this setting item.

The operand that above-mentioned each mark M610, M620, M631～M63N can be used as each order (LD order, IN order, OUT order, AND order and OR order etc.) that constitutes user program uses.In other words, the storage data of this I/O data area M5 can be referenced at user program.

The general process flow diagram of the entire process of the microprocessor that Fig. 3 represents in the CPU element to be comprised.As shown in Figure 3, in the CPU element of this PLC, started by energized, afterwards, after execution is handled (step 301) at first, repeat common processing (step 302), user program execution processing (step 303), I/O renewal processing (step 304) and peripheral server and handle (step 305).

Handle in (step 301) the various marks that the execution of executive system routine is required or the processing such as initial setting of register class initial.

Handle in (step 302) common, comprise the various hardware checks of the check of internal bus.When this hardware check, ground related to the present invention, performance element are installed and are confirmed to handle (confirmation unit is the processing that is installed to the state of connector from the state variation of connector dismounting).

Install in the affirmation processing in this unit, as being described in detail ground with reference to Fig. 5 in the back, CPU element reads the memory contents in each isolated memory area territory of internal register 12 by I/O bus 11, and based on the memory contents that is read, each state variation that whether is disassembled from the unit of carrying out a plurality of connector 13a～13d is the judgement of the state that is mounted.

Carry out in the processing (step 303) at user program, M3 reads and carries out user's user programs that suitably weave into, that be equivalent to the desired control specification of user such as using trapezoid figure language from the user program memory zone, according to this execution result, carry out the processing that the content of I/O data specified in the M5 of I/O data area is rewritten simultaneously.

Upgrade in the processing (step 304) at I/O, to be sent to the I/O unit by I/O bus 11 in the content that user program is carried out the OUT zone of the I/O data area M5 that is rewritten in the processing (step 303), the input data of carrying out being read from the I/O unit by I/O bus 11 simultaneously write the processing in the IN zone of I/O data area M5.

In peripheral service processing (step 305), carry out with the remote I/O that is connected by signal post or other PLC between communication, and these communication nodes between carry out the exchange of data, perhaps exchange by communication and instrument, thereby carry out the processing such as generation, editor, demonstration of program, and, by communication with can weave into display and exchange, thereby carry out specified internal data is presented at the peripheral service processing of outside etc.In addition, in this periphery service processing, as required, also carry out each relevant processing with various special function units (thermostat unit, PID control module, action control unit, position control unit etc.).

Between above a series of processing (step 302～305), in a plurality of connector 13a～13d some, when carrying out the fitting operation (operation of installation unit) of unit or breaking away from operation (operation of removable unit), as described later, signal by this intention of signal wire 14a～14d is sent to internal register 12, and the memory contents in the isolated memory area territory of the correspondence of internal register 12 is updated to unit installment state (first state of the present invention) or unit disengaged position (second state of the present invention).Here, " installment state of unit " is meant that the unit is installed in the state of connector, and " disengaged position of unit " is meant the state of unit from the connector dismounting.

In addition, between above a series of processing (step 302～305), when being used for the visit of reading of data for the connector that is in unit disengaged position (state that is disassembled), because of there not being corresponding unit, so become for the detected exception response of CPU element (, also still not having the state of response from this unit) even passed through the stipulated time.In the present invention, as described later, by utilizing this exception response, reduce the frequency that the unit breaks away from the reference of the required internal register (status register) 12 of the judgement of (unit is from the state variation of the installing situation for the state of dismounting), thus the processing of mitigation system side burden.

Then, illustrate between a series of processing (step 302～305), when having visited some unit, can obtain the processing of the situation of exception response.

Detail flowchart when Fig. 4 represents from unit input exception response.As shown in Figure 4, upgrade in processing or the peripheral service processing at I/O, when whenever carrying out the visit for arbitrary functional unit, each all to judge exception response have or not detection (step 401), (step 401: "No") when being judged to be the detection exception response, need not memory contents, other processing of transferring in advance to be determined with reference to internal register 12.That is, as example in the past, trying does not need the memory contents with reference to internal register 12 all the time to before the functional unit visit.

With respect to this, as result to a certain functional unit visit, (step 401: "Yes") when having judged the detection that exception response is arranged, then, read the content in each isolated memory area territory of the internal register 12 on the base unit 1, and based on this content, the connector of relevant exception response is in unit installment state (state that the unit is mounted), or the judgement (step 403) of unit disengaged position (state that the unit is disassembled).

Here, (step 403: "Yes"),,, can carry out the dismounting of functional unit, when being judged to be the unit disengaged position so (step 404) handled in the unit that puts rules into practice when breaking away from simultaneously about specified connector for the operation of former state continuation PLC.When this unit breaks away from, handle in (step 404), carry out the interruption of the communication process of relevant this connector, the processing such as disconnection of power supply, can't be after making from the data of corresponding connector read error.On the other hand, (step 403: "No"), being identified as is to result from the real communication abnormality of unusual grade of I/O bus 11, handles during the communication abnormality that puts rules into practice (step 405) when being judged to be when not being that the unit breaks away from.Handle the content of (step 405) during as this communication abnormality, can enumerate the required various processing of the system failure etc.

Like this, in the present invention, continue the operation of PLC for former state, simultaneously about specified connector, can carry out the required processing (step 404) of dismounting (the online disengaging of unit) of functional unit, detected exception response (step 401: "Yes") when CPU element has access to functional unit by certain a connector only, and the memory contents that is judged to be the internal register (status register) 12 of relevant this connector is performed (step 403: "Yes") when being disengaged position (first state), so producing need be with reference to internal register (status register) the 12nd,, only as having visited the result of unit during detected exception response, so with before CPU element is visited each functional unit, need all the time to compare with reference to the example in the past of status register at every turn, the processing of system program side burden is alleviated significantly.

On the other hand, when having visited a certain functional unit, when having produced with the real communication abnormality of the unusual grade of I/O bus as the exception response of reason, the memory contents of internal register (status register) 12 is represented installment state (second state), so handle when normally executive communication is unusual, carry out the processing of the needs of the system failure etc.

Then, illustrate to be used for the operation that former state continues PLC, about specified connector, the processing that realization can installation function unit (the online installation of unit).

The detail flowchart that Fig. 5 handles when representing unit installation judgement.As illustrated in fig. 5, in CPU element, the each arrival when handling (step 302) jointly read the memory contents of internal register 12, thus the loading and unloading state of confirmation unit.And, based on the memory contents of internal register 12, judge to have or not the unit that (unit is the state that is mounted from the state variation that is disassembled) is installed.Here, be judged as (step 502: "No"), do not carry out any processing, and transfer to determined other processing when not having the unit to install.

With respect to this, (step 502: "Yes"), transfer to following a series of processing (step 503～508) when being judged to be the unit installation.At first, by connecting the connector power supply, the unit power supply (step 503) that begins this connector is connected, read the unit identification information (constituting) of regulation simultaneously by a plurality of projects from this unit by the I/O bus, and its unit identification information (being made of a plurality of projects) that reads and store when installing in before unit checked, carry out the affirmation (step 504) of unit kind.

Here, as the above-mentioned result who checks, if be judged to be the kind of kind and the unit of installing before of unit of new installation when consistent (step 505: "Yes"), processing (step 506) when the unit that begins to stipulate is installed.When this unit is installed, handle in (step 506), carry out restart to communicate by letter etc. to each unit predetermined regular event return processing.

With respect to this, if the kind of unit that is judged to be new installation is (step 505: "No") when inconsistent with the kind of the unit of installing before, do not carry out and handle (step 506) when above-mentioned unit is installed, replace this processing, the comparison of the unit identification information (being made of a plurality of projects) of the unit identification information (being made of a plurality of projects) of the unit by new installation and the unit of being installed before generates mistaken information.Resulting so mistaken information is stored among the online swap status memory area M6 in the storer of CPU element.

As described above, in this online swap status memory area M6, comprise: online swap fault mark M610, unit kind error flag 620 and cell side are set error flag (setting 1)～(setting N) M631～M63N, handle in (step 507) in this mistaken information stores, be reflected as the state (for example, " 1 " or " 0 ") of these marks M610, M620, M631～M63N by the above-mentioned mistaken information that generates.

Therefore, the user writes user program, make these marks M610, M620, M631～M63N lights the display lamp of regulation as initial conditions, perhaps as illustrated in fig. 6, in the programable display on market, with these marks M610, M620, M631～M63N shows character or the figure that the implication content with these marks meets as initial conditions, even thereby do not have fastening means among the PLC, also can easily confirm the situation of failing in the online exchange by common display lamp or character or the figure on the programable display 6, that fails is former because made a mistake the situation of the kind of unit, made a mistake the situation etc. of which setting of cell side.

In addition, in Fig. 6, the 2nd, CPU element, the 3rd, I/O unit, the 4th, communication unit, the 5th, special function units such as action control unit or PID arithmetic element are in this example, the normal communication unit 4b of new installation has replaced from the communication unit 4a of base unit 1 Tear Down Deficiency.

At this moment, for example, if other unit are installed mistakenly, rather than communication unit is installed, then online swap fault mark M610 and unit kind error flag M620 are set to " 1 ".In addition, if made a mistake the some of setting item 1～N, then the mark of the correspondence of mark M631～M63N is set to " 1 ".

Therefore, weave into user program, make these marks M610, M620, M631～M63N lights display lamp as initial conditions, perhaps as illustrated in fig. 6, in the programable display on market, with these marks M610, M620, M631～M63N shows character or the figure that the implication content with these marks meets as initial conditions, even thereby do not have fastening means among the PLC, also can easily confirm the situation of failing in the online exchange by common display lamp or character or the figure on the programable display 6, that fails is former because made a mistake the situation of the kind of unit, made a mistake the situation etc. of which setting item of cell side.

In addition, if such mark is weaved into the user program that is equivalent to the countermeasure of elements exchange when mistaken in advance as initial conditions, then can define and continue operation etc. on the basis of actuating range or operation condition,, suitable countermeasure be taked in each this unit corresponding to mistaken kind.

Utilizability on the industry is: according to the present invention, can provide a kind of Programmable Logic Controller, and can The no instrument that carries out the unit loads and unloads online, and can alleviate system program side when the unit break away from judged Processing load.

Claims

1. Programmable Logic Controller, CPU element and a plurality of functional unit are connected to each other by the I/O bus, and each of each functional unit can install, dismantle with respect to the I/O bus by connector, and then, CPU element arrives each functional unit by the I/O bus access as required, thereby realize the function of relevant this functional unit, it is characterized in that this Programmable Logic Controller comprises:

Status register has the storage area by each connector, and interlock is in carrying out the disassembling section of functional unit about some connectors, storage first state in the storage area of relevant this connector simultaneously; And interlock is stored second state in the fitting operation that carries out functional unit about some connectors in the storage area of relevant this connector;

First control assembly, when when CPU element has access to functional unit by some connectors, detecting exception response, the memory contents of the status register of relevant this connector of reference, simultaneously when this memory contents is judged as first state, for former state continues the operation of Programmable Logic Controller, simultaneously about specified connector and the disassembling function unit, execution required processing when removable unit, on the other hand, when being judged to be second state, handle during the communication abnormality that puts rules into practice; And

Second control assembly, in the memory contents that is judged to be status register about some connectors when first state variation is second state, continue the operation of Programmable Logic Controller for former state, simultaneously about specified connector and processing required when installation unit is carried out in the installation function unit.

2. Programmable Logic Controller as claimed in claim 1 is characterized in that,

Second control assembly based on by connector from the unit identification information that functional unit read, be judged to be before and after the elements exchange in unit when inconsistent, required processing when performance element is not installed.

3. Programmable Logic Controller as claimed in claim 1 is characterized in that, also comprises:

Judging part, in the content that is judged to be status register about some connectors when first state variation is second state, based on by this connector from the unit identification information that functional unit read, judge to have or not the error unit exchange; And

The marking of control parts, with the result of determination of judging part, be reflected as can be by Programmable Logic Controller user program or the display routine of programable display come reference one or two more than the state of elements exchange error flag.

4. Programmable Logic Controller as claimed in claim 3 is characterized in that,

In the elements exchange error flag more than the display routine of user program that can be by Programmable Logic Controller or programable display comes one or two of reference, comprise the mark of the situation of failing in the online exchange of expression.

5. Programmable Logic Controller as claimed in claim 3 is characterized in that,

In the elements exchange error flag more than the display routine of user program that can be by Programmable Logic Controller or programable display comes one or two of reference, comprise the mark of situation that the kind of functional unit has been made a mistake in expression.

6. Programmable Logic Controller as claimed in claim 3 is characterized in that,

In the elements exchange error flag more than the display routine of user program that can be by Programmable Logic Controller or programable display comes one or two of reference, comprise the mark of situation of setting that a setting item of relevant cell side has been made a mistake in expression.