JP2009146040A - Data trace system using plc - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data trace system using PLC sufficiently useful for so-called data logging, for responding a desire for observing the variation of data for a long period in regard to a specific data, and to provide the PLC suitable to the above system. <P>SOLUTION: To each data acquired at predetermined timing, an identification data being specific to the above acquisition timing and having continuity as a whole is added. When a predetermined identification data transmission command is given through communication with a tool device, an up-to-date identification data at that time point is transmitted to the tool device. Further, when a predetermined trace data transmission command is given through the communication with the tool device, an up-to-date trace data at that time point is transmitted to the tool device. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a data trace system using a programmable controller (hereinafter referred to as “PLC”), and in particular, in cooperation with a PLC and a program development support device (hereinafter referred to as “tool device”). The present invention relates to a data trace system using a PLC in which trace data stored on the side can be read on the tool device side.

  Various types of data trace systems using a PLC in which trace data stored on the PLC side can be read on the tool device side in cooperation with the PLC and the tool device have been known (for example, Patent Document 1). reference).

  This type of data trace system is configured by connecting a PLC and a tool device by communication.

  As is well known to those skilled in the art, a PLC (in particular, a building block type PLC) includes a power supply unit, a CPU unit, one or more input / output units, a communication unit, various special function units, and the like. It is comprised by.

  The CPU unit is a common process for performing hardware diagnosis such as memory check, a program execution process for rewriting the contents of the input / output memory by executing a user program corresponding to the user's control specifications, and an external input terminal via an input circuit. An input / output refresh process for storing the input data that has been captured in the input area of the input / output memory and sending the output data stored in the output area of the input / output memory to the external output terminal via the output circuit; It is structured to repeatedly execute a series of processes including a peripheral service process including the communication.

  On the other hand, the tool apparatus is an information processing apparatus (for example, an input operation means including a keyboard and a mouse, an output means including an image display, an arithmetic processing means including a CPU, and a communication means with a PLC (for example, A predetermined program development support function is incorporated in a personal computer or the like).

  When the PLC receives a predetermined data acquisition start command via communication with the tool device, the PLC inputs one or more data specified in advance by the user among the variability data handled by the PLC such as input / output data. Are continuously acquired with a predetermined data acquisition timing, and the operation of sequentially writing the temporary trace data acquired in this way to a series of addresses of a trace memory having a predetermined memory capacity is repeatedly executed.

  Further, when a preset trace condition is satisfied (for example, elapse of a predetermined time, establishment of a logical condition specified by a user program, arrival of an instruction from a tool device, etc.), the PLC is set at a predetermined time (for example, The current data is continuously acquired as the actual trace data, and the actual trace data thus acquired is stored in the trace memory series. The address is sequentially written to the address, and after the trace memory is filled with the actual trace data, the acquisition of data and the writing to the trace memory are stopped.

  Further, when receiving a predetermined trace data transmission command via communication with the tool device, the PLC reads all the actual data from the trace memory and transmits it to the tool device.

  An explanatory diagram showing an example of the above-described operation in the conventional system is shown in FIG. As shown in the figure, the trace memory is divided into five blocks consisting of the first block to the fifth block in the illustrated example, and the series of blocks is divided into the first block to the fifth block. It is configured to function as a ring buffer memory that repeats addressing sequentially.

  In response to the data acquisition start command from the tool device, when the acquisition of the fluctuation data designated in advance is started, the acquired temporary trace data “1” to “5” as shown in FIG. Are sequentially stored in the first block to the fifth block, as indicated by hatching in the figure. When the first to fifth blocks are filled with the temporary trace data “1” to “5”, the data after the temporary trace data “6” is overwritten after the first block, and the temporary trace data “1”. Subsequent data is erased by overwriting.

  When a predetermined trace condition is satisfied and, for example, provisional trace data “3” and subsequent real trace data are obtained, as shown in FIG. 5B, real trace data “3” to “5” As indicated by the intermediate filling, the data is stored in the third block to the fifth block. Thereafter, the actual trace data “6” to “7” are stored in the first block to the second block, and when the actual trace data “7” is stored in the second block, the trace memory is filled with the actual trace data. Therefore, acquisition and writing of actual trace data are stopped.

In this way, when the trace memory is filled with the actual trace data, the PLC turns on the trace end relay provided on the input / output memory as shown in FIG. Can be detected. When the tool device detects that the trace end relay is turned on via communication with the PLC, the actual trace data “3” to “7” is transmitted from the PLC to the tool device in response to a transmission command from the tool device. Thus, the tool device can acquire the actual trace data “3” to “7”. The actual trace data “3” to “7” acquired in this way is used for analysis processing and display processing in the tool device.
JP 2002-351505 A

  According to such a conventional data trace system, while the temporary trace data is being acquired, the data is overwritten and erased, but after the trace condition is satisfied (for example, occurrence of a failure), the trace memory Since the data writing is stopped after waiting for the actual trace data to be satisfied, there is an advantage that the actual trace data is not overwritten and erased.

  However, in the above-described data trace system, the amount of real trace data that can be acquired depends on the capacity of the trace memory, so that it is said that the change in the trace target data is observed in a relatively short period before and after the trace condition is established. Although it can withstand limited applications, it cannot be used for so-called data logging applications where it is desired to observe the fluctuation of specific data over a long period of time regardless of whether or not the trace condition is satisfied. There was a point.

  The present invention has been made paying attention to the above-mentioned problems, and the object of the present invention is sufficient for so-called data logging applications in which it is desired to observe the fluctuation of specific data over a long period of time. The object is to provide a data trace system using the obtained PLC and a PLC suitable for the system.

  Other objects and operational effects of the present invention will be easily understood by those skilled in the art by referring to the following description of the specification.

  It is considered that the above technical problem can be solved by a PLC data trace system having the following configuration.

  That is, this data trace system is configured by connecting the PLC and the tool device by communication.

  Here, the PLC is a common process for performing hardware diagnosis such as a memory check, a program execution process for executing a user program corresponding to the user's control specifications and rewriting the contents of the input / output memory, and an external input via an input circuit. Input / output refresh processing and tool that stores input data captured from the terminal in the input area of the input / output memory and sends the output data stored in the output area of the input / output memory to the external output terminal via the output circuit A series of processing including peripheral service processing including communication with the apparatus is repeatedly executed.

  In addition, the tool device is provided with an information processing apparatus including an input operation unit including a keyboard and a mouse, an output unit including an image display unit, an arithmetic processing unit including a CPU and the like, and a communication unit with a PLC. The program development support function is incorporated.

  The PLC is provided with “data tracing means”, “identification data providing means”, “identification data transmitting means”, and “trace data transmitting means”.

  When a predetermined trace start command is given through communication with the tool device, the data trace means is 1 or 2 designated in advance by the user in the variability data handled by the PLC such as input / output data. The above data is continuously acquired at a predetermined data acquisition timing, and the operation of sequentially writing the acquired trace data to a series of addresses of a trace memory having a predetermined memory capacity is repeatedly executed.

  The identification data adding unit adds continuous identification data (for example, serial number, time information on the order of milliseconds, etc.) to each of the data acquired at a predetermined timing by the data tracing unit.

  When a predetermined identification data transmission command is given through communication with the tool device, the identification data transmitting means transmits the latest identification data to the tool device at that time.

  When a predetermined trace data transmission command is given through communication with the tool device, the trace data transmission means transmits the latest trace data to the tool device at that time.

  On the other hand, the tool device is provided with “trace start command means”, “latest data inquiry means”, “trace data transmission request command means”, and “trace data storage means”.

  The trace start command means generates a trace start command in response to a predetermined operation on the input operation means, and transmits the trace start command thus generated to the PLC via the communication means.

  The latest data inquiry means, after giving a trace start command, repeatedly transmits a predetermined identification data transmission command for requesting transmission of the latest identification data to the PLC at a predetermined timing via the communication means. The latest identification data returned from the PLC is received via the communication means. Here, the “predetermined timing” can be set at regular time intervals (periodically), for example. Since this time interval is affected by the communication performance, it is automatically calculated on the tool device side, or an appropriate value is set on the user side.

  The trace data transmission request command means collates the latest identification data received from the PLC in this way with the latest identification data held by itself, and the latest identification data received from the PLC rather than the latest identification data held by itself. When this is newer, a predetermined trace data transmission command for requesting transmission of the latest trace data is transmitted to the PLC via the communication means.

  The trace data storage means receives the trace data returned from the PLC via the communication means, and stores the trace data received from the PLC in this way in a series of addresses of a predetermined logging memory in association with the identification data.

  According to such a configuration, after the data trace is started on the PLC side, the identification data corresponding to the latest trace data is sent from the PLC to the tool every time a regular inquiry is made from the tool device side. While it is returned to the device, the tool device compares it with the acquired identification data, detects that the PLC has acquired new trace data, makes a transmission request to the PLC, and responds As new trace data is acquired and saved in the logging memory, even if past trace data is overwritten on the PLC side trace memory, it is overwritten as long as the inquiry frequency from the tool device is appropriate. Each trace data will be saved in the tool device before starting the ring buffer. Even while using the trace memory, it is possible to realize a data trace system using a PLC can be sufficiently subjected to a long period of time over with so-called data logging applications said to be observed that vary for particular data.

  Moreover, since a series of trace data stored in the data logging memory in this way is given continuous identification data, due to the difference between the inquiry timing from the tool device and the trace data acquisition timing, etc. When a part of continuous trace data is missing, the continuity of a series of identification data is interrupted, so that it is easy to find such missing trace data.

  The predetermined data acquisition timing in the PLC includes various timings such as a timing at which a predetermined time elapses, a timing at which a predetermined trace instruction incorporated in the user program is executed, or a timing at which a cycle time elapses. Can be adopted.

  The present invention viewed from another aspect can be grasped as a PLC suitable for the above-described data trace system.

  This PLC is a common process that performs hardware diagnosis such as memory check, a program execution process that executes a user program corresponding to the user's control specifications and rewrites the contents of the input / output memory, and an external input terminal via an input circuit. An input / output refresh process for storing the input data that has been captured in the input area of the input / output memory and sending the output data stored in the output area of the input / output memory to the external output terminal via the output circuit; It is structured to repeatedly execute a series of processes including a peripheral service process including the communication.

  Further, the PLC is provided with “data tracing means”, “identification data providing means”, “identification data transmitting means”, and “trace data transmitting means”.

  When a predetermined trace start command is given through communication with the tool device, the data trace means is 1 or 2 designated in advance by the user in the variability data handled by the PLC such as input / output data. The above data is continuously acquired at a predetermined data acquisition timing, and the operation of sequentially writing the acquired trace data to a series of addresses of a trace memory having a predetermined memory capacity is repeatedly executed.

  The identification data adding unit adds identification data unique to the acquisition timing and continuous as a whole to each of the data acquired at a predetermined timing by the data tracing unit.

  When a predetermined identification data transmission command is given through communication with the tool device, the identification data transmitting means transmits the latest identification data to the tool device at that time.

  When a predetermined trace data transmission command is given through communication with the tool device, the trace data transmission means transmits the latest trace data to the tool device at that time.

  According to such a configuration, the start of the data trace, the transmission of the identification data related to the latest trace data, and the transmission of the latest trace data all operate in response to a predetermined command from the outside. By giving a simple command, the data logging function can be realized by appropriately cooperating this and the tool device while using the conventional trace memory in the PLC.

  As the predetermined data acquisition timing in the PLC, every time a certain time elapses, a timing at which a predetermined trace instruction incorporated in the user program is executed, every time a cycle time elapses, etc. Various timings can be employed.

  According to the present invention, there is provided a data trace system using a PLC that can be sufficiently used for so-called data logging applications in which specific data is desired to be observed over a long period of time, and a PLC suitable for the system. can do.

  A preferred embodiment of a data trace system using a PLC according to the present invention will be described below in detail with reference to the accompanying drawings.

  A block diagram of the system of the present invention is shown in FIG. As shown in the figure, the data trace system according to the present invention is configured by connecting a PLC 1 and a program development support device (tool device) 2 with a communication cable 3. In the illustrated example, a building block type PLC including a power source unit 11, a CPU unit 12, an input unit 13, an output unit 14, and a communication unit 15 is employed as the PLC 1.

  As is well known to those skilled in the art, each of these units 11-15 has a generally bookcase-type housing and a socket on an internal bus laid on the backplane located behind it. On the other hand, they can be attached to and detached from each other, and can exchange data with each other via an internal bus.

  The power supply unit 11 can supply power to the other units 12 to 15 through a power supply line on the internal bus. The input unit 13 includes an input terminal block to which a predetermined number of external input devices are wired and an input circuit for taking in signals from the input devices wired to the input terminal block. The output unit 14 includes an output terminal block to which a predetermined number of output devices are wired, and an output circuit for sending an output signal to the output devices wired to the output terminal block.

  The communication unit 15 includes a shared memory for exchanging data with the CPU unit 12 described later, a transmission / reception circuit for transmitting / receiving data to / from the tool device 2 via the communication cable 3, and a CPU. A control unit (microprocessor) that performs overall control of data exchange with the unit 12 and communication with the tool device 2 is included.

  The CPU unit 12 performs overall control of the entire PLC 1, and a hardware configuration diagram thereof is shown in FIG. As shown in the figure, the CPU unit 12 includes a microprocessor (MPU) 121, a system memory (SROM) 122, a backup memory (BROM) 123, a work memory (WRAM) 124, a user memory (UM) 125, and external support. A circuit (ASIC) 126 and an input / output memory (IOM) 127 are included.

  The microprocessor (MPU) 121 performs overall control of the entire CPU unit 12, and executes various system functions stored in a system memory (SROM) 122, which will be described later, thereby performing various functions necessary for the CPU unit 12. Is configured to realize.

  In this example, the system memory (SROM) 122 is composed of a nonvolatile memory such as a flash memory, and stores various system programs executed by the microprocessor (MPU) 121 as described above. . Specifically, a series of processes in the flowchart of FIG. 2 (steps 151 to 154) described later, a series of processes in the flowchart in FIG. 3 (steps 201 to 205), and a series of processes in FIG. 4 to FIG. 305, steps 311 to 313, and steps 321 to 324) correspond to this.

  The backup memory (BROM) 123 is composed of a non-volatile memory such as a flash memory, and is configured to retain the contents even when the battery is not present when the power is turned off. In this backup memory (BROM) 123, a user program corresponding to the control specifications of the PLC is created in a predetermined program language (for example, a ladder diagram language), and an external support circuit (ASIC) 126 or a microprocessor (MPU) ) 121 is converted into executable code and stored.

  The work memory (WRAM) 124 functions as a work area when the microprocessor (MPU) 121 executes a system program read from the system memory (SROM) 122, and includes a rewritable RAM. Yes. A trace memory (TM) to be described later is provided in the work memory (WRAM) 124.

  The user memory (UM) 125 is composed of a static RAM (SRAM), and cannot hold contents when the power is turned off. The user memory (UM) 125 stores a user program transferred from the backup memory (BROM) 123 when the power is turned on.

  The external support circuit (ASIC) 126 is configured by an application specific IC (ASIC: Application Specific IC) in which a user program execution function is structured, and each of the user programs that are read from the user memory (UM) 125 is configured. Instructions are configured to be executed sequentially.

  The input / output memory (IOM) 127 is referred to when the external support circuit (ASIC) 126 executes a user program read from the user memory (UM) 125, and includes an I / O bus therein. 4, input / output data areas corresponding to the data of the input / output terminal blocks of the input / output units 12 and 13 connected via 4, an auxiliary relay area used only for internal computation, and various setting data used during computation ( Parameter), a data area for storing count data, and the like. A trace end relay described later is provided in the input / output memory (IOM) 127.

  On the other hand, the tool device (program development support device) 2 is based on a personal computer system having a personal computer main body 21, an image monitor 22, a mouse 23, and a keyboard 24, as shown in FIG. For example, it is configured by incorporating an application program (an application program that realizes a function as a program development support apparatus) that operates on an OS such as Windows (registered trademark).

  As is well known to those skilled in the art, as an application program as a program development support device, a program creation function, an editing function, an upload function via communication from the PLC, and a download function via communication to the PLC are realized. In particular, in this example, a program for realizing a series of processes (steps 101 to 107) shown in the flowchart of FIG. 2, which will be described later in connection with the present invention, Furthermore, a program for realizing functions such as analysis and display of data stored in the logging memory on a monitor is also included. A logging memory (LM), which will be described later, is provided in a work memory in the personal computer main body 21.

  Next, the cooperative relationship between the PLC 1 and the tool device 2 will be described with reference to a flowchart showing the operation of the system of the present invention.

  A flowchart showing the operation of the system of the present invention is shown in FIG. When the processing is started in the figure, first, on the tool device (program development support device) 2 side, a trace start processing (step 101) is executed. In this trace start process (step 101), as shown in FIG. 7 (1), a trace start command is generated in response to a predetermined operation on the mouse 23 or keyboard 24, and the trace start command thus generated is displayed. Processing to transmit to the PLC 1 via the communication means is executed. In this example, a serial number is adopted as the trace ID for identifying the trace data. At this time, the serial number “0” is initially set as the latest acquired trace ID on the tool device 2 side. Is set.

  On the side of the PLC that has received the trace start command (command), one or two or more data designated in advance by the user among the variability data handled by the PLC 1 such as input / output data is obtained at a predetermined data acquisition timing. In addition to continuously acquiring, the operation of sequentially writing the acquired trace data to a series of addresses of the trace memory (TM) having a predetermined memory capacity is repeatedly executed (step 151). At the same time, on the PLC side, continuous identification data is assigned to each data acquired at a predetermined timing. Examples of such identification data having continuity include serial numbers and time information on the order of milliseconds.

  Here, with regard to the trace data acquisition timing, in this example, the user can arbitrarily select one of “TRSM instruction execution specification”, “each cycle specification”, and “constant time interval specification”. Has been made.

  As is well known to those skilled in the art, in this type of PLC 1, as shown in the flowchart of FIG. 3, after executing power-on processing (step 201) following power-on, Common processing for performing hardware diagnosis such as memory check (step 202), program execution processing for rewriting the contents of the input / output memory by executing a user program corresponding to the user's control specifications (step 203), via an input circuit Input / output refresh processing that stores the input data fetched from the external input terminal in the input area of the input / output memory and sends the output data stored in the output area of the input / output memory to the external output terminal via the output circuit (Step 204), a series of processing including peripheral service processing (step 205) including communication with the tool device 2 is repeated. It has been orchestrated so as to return execution.

  When “TRSM instruction execution time designation” is selected as the trace data acquisition timing, the trace data is acquired at the timing of the program execution process (step 203). When “designate every cycle” is selected as the trace data acquisition timing, after the program execution process (step 203) is completed, the input of the trace data is started before the input / output refresh process (step 204) is started. Acquisition is performed. Further, when “specified time interval designation” is selected as the trace data acquisition timing, the trace data is acquired with a fixed interruption regardless of the process being executed.

  FIG. 4 is an explanatory diagram of trace data acquisition in the case of “designation at the time of execution of a TRSM instruction”. As shown in the figure, in the program execution process (step 203), each instruction constituting the user program is sequentially read from the user memory (UM) 125 (step 305) and is decoded. Then, it is determined whether the instruction is a “TRSM instruction” or any other instruction (step 301). If the decoded instruction is an instruction other than the “TRSM instruction” (NO in step 301), processing corresponding to the decoded instruction is executed (step 302). On the other hand, when the decoded instruction is the “TRMS” instruction, it is further determined whether or not the setting of the trace data collection timing is “when the TRMS instruction is executed” (step 303). The trace data acquisition process (step 304) is executed and the trace data is acquired only when the trace data collection timing is set to “when the TRMS instruction is executed”.

  FIG. 5 shows an explanatory diagram of trace data acquisition in the case of “designate every cycle”. As shown in the figure, when the predetermined mode flag is “Trace in progress” (Step 311 YES), if it is determined that the setting of the trace data collection timing is “Every cycle” (Step 312 YES), Further, it is determined whether or not the current time is the timing immediately after the end of the program execution process (step 203) (step 312). Only when it is the time immediately after the end (step 313 YES), the trace data acquisition process (step 312) is performed. 314) is executed to acquire trace data.

  FIG. 6 shows an explanatory diagram of trace data acquisition in the case of “specified time interval designation”. As shown in the figure, when a scheduled interrupt (for example, every 10 ms) is started and the predetermined mode flag is “Trace being executed” (step 321 YES), the trace data collection timing is set to “fixed time”. If it is determined that the interval is “interval” (step 322 YES), it is further determined whether or not a predetermined time defining the trace data acquisition interval has elapsed (step 323), and only when the predetermined time has elapsed (step 323). 323 YES), the trace data acquisition process (step 324) is executed to acquire the trace data.

  Returning to the flowchart of FIG. 2, following the trace start process (step 101), on the tool device 2 side, the trace state monitoring process (step 102) for monitoring the trace execution state of the PLC and the trace mode state in the PLC are changed. The trace continuation determination process (step 103) for determining whether or not it is continued, and the previously acquired trace ID and the current trace ID are collated, whereby the current trace ID is the previously acquired trace ID. Data update determination process (step 104) for determining whether or not the data is newer, trace read process (step 105) and trace data executed on condition that the determination of the data update determination process (step 104) is affirmed The storage process (step 106) is repeatedly executed.

  More specifically, in the trace state monitoring process (step 102), the tool device sends a trace ID transmission command at a predetermined timing via the communication means in order to inquire the PLC for the latest trace ID (identification data). While repeatedly transmitting, the latest trace ID and trace state (status) returned from the PLC in response to this are received and stored via the communication means. At this time, in the process of collecting trace data on the PLC 1 side (step 152), every time a trace ID transmission command is received from the tool device 2 while collecting trace data, the latest trace data is handled. The trace ID is read from the trace memory (TM) and returned to the tool device 2. At the same time, the PLC 1 also transmits to the tool device 2 the status of whether the PLC status (status) at that time is trace execution or trace stop.

  In the trace continuation determination process (step 103), based on the PLC state (status) received from the PLC 1 side, it is determined whether the PLC state is executing the trace or the trace is stopped. If it is determined (NO in step 103), a trace stop command (step 107) is executed to transmit a trace interruption command to the PLC via the communication means. In response to this, the PLC side ends the data trace by executing a trace end process (step 154).

  In the data update determination process (step 104), the latest identification data received from the PLC is compared with the latest identification data held by the self, and the latest identification data received from the PLC is compared with the latest identification data held by the self. It is determined whether or not the identification data is newer, and the process proceeds to the trace data reading process (step 105) on the condition that this determination is affirmed.

  In the trace data reading process (step 105), a predetermined trace data transmission command for requesting transmission of the latest trace data is transmitted to the PLC via the communication means, and in response thereto, the PLC side returns a response. The process of receiving the latest trace data, the status of whether the trace is being executed or stopped, and the latest trace ID is executed. At this time, in the process of collecting trace data on the PLC side (step 153), every time a trace data transmission command is received from the PLC while collecting trace data, the latest trace data is stored in the trace memory (TM ) And return to the tool device 2. At the same time, the PLC 1 also transmits to the tool device 2 the status (status) of the PLC at that time, whether the trace is being executed or the trace is stopped, and the latest trace ID.

  In the trace data storing process (step 106), the trace data received from the PLC is stored in a series of addresses of a predetermined logging memory (LM) in association with the trace ID (identification data).

  Trace execution by repeatedly executing the trace state monitoring process (step 102), the data update determination process (step 104), the trace data reading process (step 105), and the trace data saving process (step 106) on the tool device side. FIG. 7 is an explanatory diagram (part 1) showing the flow inside, and FIG. 8 is an explanatory diagram (part 2) thereof.

  At the time of starting the trace, as shown in FIG. 7A, the trace memory (TM) of the PLC 1 is empty, and the latest trace ID acquired by the tool device (program development support device) 2 is obtained. Is a serial number “0”. In this state, when a predetermined trace start operation is performed on the tool device 2 side, a trace start command is transmitted from the tool device 2 to the PLC 1. The illustrated trace memory (TM) is divided into five blocks including a first block to a fifth block, and functions as a ring buffer. Therefore, the first block (trace data “1”) → the second block ( Trace data “2”) → ・ ・ ・ Fifth block (trace data “5”) → first block (trace data “6”) → second block (trace data “7”) Trace data is repeatedly written (overwritten) to the first to fifth blocks while the address is circulated in the range of “1” to “5”.

  Immediately after the start of tracing, as shown in FIG. 7B, the trace memory (TM) of the PLC 1 is still empty and acquired by the tool device (program development support device) 2. The latest trace ID is also a serial number “0”. Therefore, the latest trace ID that is answered ((2) -2) to the latest trace ID inquiry ((2) -1) is still “0”, and the data update determination process (step 104) is performed. Therefore, the trace data reading process (step 105) and the trace data saving process (step 106) are not executed.

  When the PLC acquires the trace data “1”, the trace data “1” is stored in the first block of the trace memory (TM) of the PLC 1 as shown in FIG. The latest trace ID acquired on the device 2 side is mainly set to “0”.

  After the PLC has acquired the trace data “1”, as shown in the upper part of FIG. 8 (4), an answer ((4) − 2) Since the latest trace ID to be set is “1”, the data update determination process (step 104) is affirmed, and as shown in the middle part of FIG. As a result, the latest trace data “1” is read from the PLC 1 ((4) -3), and the latest trace ID acquired by the tool device 2 is “1”.

  After the tool device 2 has acquired the latest trace ID “1”, as shown in the lower part of FIG. 8 (4), the latest trace ID inquiry ((4) -4) is answered. Since ((4) -5) is still “1” and the data update determination process (step 104) is denied, the trace data reading process (step 105) and the trace data saving process (step 106) are performed. Not executed.

  After the PLC 1 has acquired the trace data “2”, as shown in FIG. 8 (5), the first and second blocks of the trace memory (TM) of the PLC 1 include the trace data “1” and Since “2” is stored and the latest trace ID acquired by the tool device 2 remains “1”, thereafter, every time the latest trace data is updated on the PLC side in the same manner. On the tool device side, a trace data reading process (step 105) and a trace data saving process (step 106) are executed.

  In this way, as shown in the flowchart of FIG. 2, the cooperation between the PLC and the tool device causes the trace data generated on the PLC trace memory (TM) to be stored in the logging memory (LM) of the tool device. ) So that a large amount of logging data can be generated on the logging memory (LM) of the tool device while using a relatively small capacity trace memory (TM). is there.

  FIG. 9 shows an explanatory diagram showing a flow from the trace data acquisition by the PLC to the logging data acquisition by the tool device.

  As shown in FIGS. 4A to 4D, every time new trace data is stored in each block of the PLC trace memory (TM), the newly stored trace data is read from the PLC. Then, it is transferred to the logging memory (LM). Even after the first to fifth blocks of the trace memory (TM) are full and overwriting to the trace memory (TM) is started, newly acquired trace data “6”, “7”. .. Is read from the trace memory (TM) and transferred to the logging memory (LM) each time. On the other hand, the past trace data “1”, “2”,... Are sequentially deleted by the endorsement processing on the trace memory (TM), but the past log data (LM) on the tool device side is stored in the past. All trace data “1”, “2”... Remain, so that a relatively small amount of trace memory (TM) is used, but a large amount is recorded on the logging memory (LM) of the tool device. Logging data of the size can be generated.

  In addition, in this embodiment, since the conventional trace memory (TM) is used as it is, the data logging function according to the present invention and the conventional conditional trace function coexist, and these can be arbitrarily set. It can also be made switchable.

  In the above embodiment, as shown in FIG. 1A, the communication unit 15 is interposed between the PLC 1 and the tool device 2, but this is merely a person showing an example of the communication form. . In an all-in-one type PLC, a transceiver will be incorporated in a single housing, and in some building block type PLCs, a transceiver is incorporated in the CPU unit 12. Let's go.

  In the above embodiment, the PLC and the tool device are connected by a dedicated cable to perform one-to-one communication. In addition, the PLC and the tool device are connected via a network to remotely Communication may be performed between the arranged tool device and the PLC.

  Assuming this kind of network communication, even though the planned communication frequency should be in time for the trace data acquisition frequency, it is assumed that trace data may be lost due to the degree of congestion on the line. In the system of the present invention, since identification information having continuity is attached to each of the trace data, even if such trace data is lost, the fact that the continuity of the identification data is detected. It can be easily detected based on the break.

  FIG. 10 shows an explanatory diagram of such detection of missing trace data. As shown in (a) of the figure, when the trace ID is a serial number, as shown in (b) of the figure, the trace ID is stored in the logging memory (LM) regardless of whether the trace ID is time information. Based on the discontinuity of the trace ID in the series of stored data strings, it is possible to easily detect missing trace data.

  Further, in order to execute data trace, it is necessary to set various trace parameters while looking at the screen of the tool device. An explanatory view (No. 1) of such a trace parameter setting screen is shown in FIG. 11, and an explanatory view (No. 2) is shown in FIG.

  As shown in FIG. 11A, prior to data tracing, according to the screen of the tool device, according to the variable / address related to the trace target data, the edge type as a reference for the trace data acquisition timing, and the delay time from the edge Set each. Also, as shown in FIG. 11B, it is set whether the trace data acquisition mode is “fixed interval”, “every cycle”, or “by TRSM instruction”. Further, as shown in FIG. 12A, the type of the tray target word data is set to “1 word” or “2 words”. Further, as shown in FIG. 12B, settings such as address selection of the trace target bit are performed.

  An example of the format of the trace data acquired under such settings is shown in FIG. As shown in the figure, the first two words of the trace memory are trace data (ID # 1, ID # 2), and the next two words are 32 contact data (s0 to s31). Sampling data 1 to x are stored in the word.

  FIG. 14 is an explanatory diagram (part 1) of an analysis example of the logging data acquired in this way in the tool device (program development support device), FIG. 15 is an explanatory diagram (part 2) thereof, and an explanation of the trace result display screen The figures are shown in FIG.

  In the tool device (program development support device), as shown in the flowchart of FIG. 15, according to a predetermined application program, first, the trace data is arranged in order according to the trace ID (step 401) and set to the trace parameter. The set address and the contact value of the trace data are combined (step 402), the CH address set in the trace parameter and the CH value of the trace data are combined (step 403), and finally the above information is shown in FIG. Thus, it is visually expressed on the monitor screen (step 404).

  As described above, according to the data trace system according to the above embodiment, after the data trace is started on the PLC 1 side, the latest trace is obtained every time a periodic inquiry is made from the tool device 2 side. While the identification data (serial number, time information, etc.) corresponding to the data is returned from the PLC 1 to the tool device 2, the tool device 2 compares this with the acquired identification data, and the PLC obtains new trace data. It detects that it has been acquired, makes a transmission request to the PLC side, acquires new trace data as a response, and saves it in the logging memory (LM). In the past on the trace memory (TM) on the PLC 1 side Even if the trace data is overwritten, as long as the inquiry frequency from the tool device 2 is appropriate, The trace data will be stored on the tool device 2 side. Therefore, while using a conventional ring buffer type trace memory (TM), it is desired to observe the fluctuation of specific data over a long period of time. A data trace system using a PLC that can be sufficiently used for the so-called data logging application can be realized.

  Moreover, since a series of trace data stored in the data logging memory (LM) in this way is given identification data that is unique to the acquisition timing and continuous as a whole, the tool device 2 If a part of the continuous trace data is lost due to the difference between the inquiry timing from the trace data and the trace data acquisition timing, etc., the continuity of the series of identification data is interrupted, and the trace data is lost. Easy to find.

  According to the present invention, there is provided a data trace system using a PLC that can be sufficiently used for so-called data logging applications where it is desired to observe fluctuations of specific data over a long period of time, and a PLC suitable for the system. can do.

It is explanatory drawing of the PLC system which concerns on this invention, and its component. It is a flowchart which shows operation | movement of this invention system. It is explanatory drawing of the acquisition timing of the trace data by PLC, and the read timing of the trace data by a tool. It is explanatory drawing of trace data acquisition in the case of "designation at the time of TRSM instruction execution". It is explanatory drawing of trace data acquisition in the case of "each cycle designation". It is explanatory drawing of trace data acquisition in the case of "a fixed time interval designation | designated." It is explanatory drawing (the 1) which shows the flow during trace execution. It is explanatory drawing (the 2) which shows the flow during trace execution. It is explanatory drawing of the flow of logging data acquisition by a tool apparatus from the trace data acquisition by PLC. It is explanatory drawing of the detection of trace data. It is explanatory drawing (the 1) of a trace parameter setting screen. It is explanatory drawing (the 2) of a trace parameter setting screen. It is explanatory drawing which shows an example of the format of trace data. It is explanatory drawing (the 1) of the example of an analysis in a program development assistance apparatus. It is explanatory drawing (the 2) of the example of an analysis in a program development assistance apparatus. It is explanatory drawing of the example of a trace result display screen. It is explanatory drawing which shows the operation | movement in a conventional system.

Explanation of symbols

1 PLC
2 Program Development Support Device 3 Communication Cable 4 I / O Bus 11 Power Supply Unit 12 CPU Unit 121 MPU
122 SROM
123 BROM
124 WRAM
125 UM
126 ASIC
127 IOM
13 Input Unit 14 Output Unit 15 Communication Unit 21 Personal Computer Body 22 Monitor 23 Mouse 24 Keyboard

Claims (4)

Common processing to perform hardware diagnosis such as memory check, program execution processing to rewrite the contents of the input / output memory by executing the user program corresponding to the user's control specifications, input taken from the external input terminal via the input circuit Includes input / output refresh processing for storing data in the input area of the input / output memory and sending output data stored in the output area of the input / output memory to the external output terminal via the output circuit, and communication with the tool device A PLC structured to repeatedly execute a series of processes including peripheral service processes,
A predetermined program development support function in an information processing apparatus having an input operation means including a keyboard and a mouse, an output means including an image display, an arithmetic processing means including a CPU, and a communication means with a PLC. In addition, the PLC includes a tool device constructed by incorporating
When a predetermined trace start command is given through communication with the tool device, one or more data designated in advance by the user among the variability data handled by the PLC such as input / output data, Data trace means for continuously executing with a predetermined data acquisition timing and repeatedly executing an operation for sequentially writing the acquired trace data to a series of addresses of a trace memory having a predetermined memory capacity;
Identification data giving means for giving continuous identification data to each of the data acquired at a predetermined timing by the data tracing means,
When a predetermined identification data transmission command is given through communication with the tool device, identification data transmission means for transmitting the latest identification data to the tool device at that time,
Trace data transmission means is provided for transmitting the latest trace data to the tool device at that time when a predetermined trace data transmission command is given through communication with the tool device,
Tool equipment includes
A trace start command means for generating a trace start command in response to a predetermined operation in the input operation means, and transmitting the trace start command thus generated to the PLC via the communication means;
After giving the trace start command, a predetermined identification data transmission command for requesting transmission of the latest identification data is repeatedly transmitted to the PLC at a predetermined timing via the communication means, while the latest information returned from the PLC is returned. Latest data inquiry means for receiving the identification data via the communication means,
The latest identification data received from the PLC is checked against the latest identification data held by the self, and when the latest identification data received from the PLC is newer than the latest identification data held by the PLC, the latest trace data is stored. Trace data transmission request command means for transmitting a predetermined trace data transmission command for requesting data transmission to the PLC via the communication means;
Trace data storage means for receiving the trace data returned from the PLC via the communication means and storing the trace data received from the PLC in a series of addresses of a predetermined logging memory in association with the identification data is provided. The data trace system using PLC characterized by the above-mentioned.   The predetermined data acquisition timing in the PLC is a timing at which a predetermined time elapses, a timing at which a predetermined trace instruction incorporated in a user program is executed, or a timing at which a cycle time elapses. A data trace system using the PLC according to claim 1. Common processing to perform hardware diagnosis such as memory check, program execution processing to rewrite the contents of the input / output memory by executing the user program corresponding to the user's control specifications, input taken from the external input terminal via the input circuit Includes input / output refresh processing for storing data in the input area of the input / output memory and sending output data stored in the output area of the input / output memory to the external output terminal via the output circuit, and communication with the tool device It is designed to repeatedly execute a series of processing including peripheral service processing.
When a predetermined trace start command is given through communication with the tool device, one or more data designated in advance by the user among the variability data handled by the PLC such as input / output data, Data trace means for continuously executing with a predetermined data acquisition timing and repeatedly executing an operation for sequentially writing the acquired trace data to a series of addresses of a trace memory having a predetermined memory capacity;
Identification data giving means for giving continuous identification data to each of the data acquired at a predetermined timing by the data tracing means,
Identification data transmission means for transmitting the latest identification data to the tool device at that time when a predetermined identification data transmission command is given through communication with the tool device;
And a trace data transmitting means for transmitting the latest trace data to the tool device at the time when a predetermined trace data transmission command is given through communication with the tool device. .   The predetermined data acquisition timing in the PLC is a timing at which a predetermined time elapses, a timing at which a predetermined trace instruction incorporated in a user program is executed, or a timing at which a cycle time elapses. The PLC according to claim 3.

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