Slave station identification scheme for control / monitoring signal transmission system

Abstract

In the present invention, one of a prescribed number of numerical values is set as a primary temporary address for each of a plurality of slave stations that transmit data to and receive data from a master station by using a transmission synchronization scheme over a shared transmission line. The master station successively designates all the numerical values that could possibly be set as the primary temporary addresses, and on the basis of the reply sent via a management data region from a slave station having a primary temporary address matching the designated numerical value, it is determined whether there is an overlap among primary temporary addresses. Via the management data region, slave stations for which the set primary temporary address is determined to have no overlap are each imparted, as an identification number, a numerical value from among pre-prepared numerical values that has been not imparted to any of the other slave stations, the numerical values all differing from one another and the number of said numerical values corresponding to the number of slave stations. After a different identification number is imparted to each slave station, the identification numbers are successively designated, the slave station having an imparted identification number matching the designated identification number transmits, via the management data region, a label that has been preset for the slave station and that is associated with slave station identification information with which the slave station can be identified to the master station, and an address which is assigned to each slave station is associated with the label.

Description

Method for identifying slave stations in control and monitoring signal transmission systems

[0001] The present invention relates to a method for identifying a target slave station from among multiple slave stations installed away from a control side device in a control / monitoring signal transmission system that reduces the number of signal lines between a master station on the controlling side and multiple slave stations on the controlled side, connects them with a common transmission line, and transmits data using a transmission synchronization method such as synchronization with a transmission clock.

[0002] In control systems including a control unit and a plurality of output units and input units, or a plurality of controlled devices, a reduction in the number of wires, i.e., so-called wire reduction, is widely practiced. A commonly adopted method for reducing the number of wires is to connect a master station and a plurality of slave stations, each equipped with a function for converting parallel signals to serial signals, to the control unit and the plurality of output units and input units, or the plurality of controlled devices, respectively, and transmit and receive data between the master station and the plurality of slave stations by serial signals via a common data signal line, instead of a parallel connection in which each of the signal lines extending from the plurality of output units and input units, or the controlled devices, is directly connected to the control unit.

[0003] Furthermore, since slave stations used to reduce the wiring for transmission signals generally do not have device-specific identifiers such as Ethernet MAC addresses, in a system in which data is exchanged between a master station and multiple slave stations by serial signals over a common data signal line, a data area for the transmission signal is assigned to each of the multiple slave stations, and an address is set in each slave station for obtaining the timing of the data area assigned to that station. Each of the multiple slave stations exchanges data with the master station in the data area assigned to that station, thereby preventing collisions between transmission and reception among the multiple slave stations.

[0004] However, the address set for a slave station does not indicate the characteristics of the slave station, such as its installed location, input / output type, or purpose, which can cause problems when performing work involving human intervention. For example, when taking measures such as repair or replacement, inspection, or setting changes, it is necessary to identify the target slave station at the site where the slave station is installed, which can be time-consuming and labor-intensive.

[0005] Therefore, the present applicant has proposed a slave station identification method disclosed in Japanese Patent Application Laid-Open No. 2021-34851. In this slave station identification method, one of a predetermined number of numerical values ​​is set as a primary temporary address for each slave station, and an inquiry process, a duplication determination process, a secondary temporary address setting process, and a primary temporary address resetting process are repeated until there are no more duplicate primary temporary addresses. After a different secondary temporary address is set for each slave station, an address indicating the start position of the control and monitoring data area in the data area in the control and monitoring data area assigned to each slave station is associated with slave station identification information that can identify the slave station and is set to each slave station using the secondary temporary address, corresponding to a label that is pre-set for the slave station. This makes it possible to identify the slave station by the label.

[0006] Japanese Patent Application Laid-Open No. 2021-34851

[0007] However, in the conventional slave station identification method, the number of digits in the secondary temporary address increases as the number of times the inquiry process, duplication determination process, secondary temporary address setting process, and primary temporary address resetting process are repeated increases. Therefore, in situations where the number of times the above processes are repeated increases and the secondary temporary address data is expected to exceed the transmittable data capacity, for example, in situations where the number of connected slave stations increases and the number of duplications increases, it may be difficult to use the conventional slave station identification method.

[0008] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a slave station identification method that allows a slave station to be easily identified through manual work even in situations where it is difficult to use conventional slave station identification methods.

[0009] In a control and monitoring signal transmission system according to the present invention, a master station transmits and receives data to and from a control unit, and a plurality of slave stations transmit and receive data to and from the master station via a common transmission line using a synchronous transmission method, and data is exchanged between the master station and the slave stations by superimposing data onto frames repeatedly transmitted from the master station, the frames are time-divided, and a control and monitoring data area in which the direction of data transmission is determined and assigned to each of the slave stations, and a management data area separate from the control and monitoring data area, is provided for use in exchanging data with all of the slave stations, and one of a predetermined number of numerical values ​​is set as a primary temporary address for each of the slave stations, and the inquiry step, duplication determination step, identification number assignment step, and primary temporary address resetting step are repeated until all of the identification numbers, all of which are different and corresponding to the number of the slave stations, are assigned as identification numbers to each of the slave stations to which a unique primary temporary address has been set.

[0010] In the inquiry step, all the numerical values ​​that may be set as the primary temporary addresses are sequentially designated from the master station via the management data area, and an inquiry is made to the slave station.

[0011] In the duplication determination step, it is determined whether or not the primary temporary address is duplicated based on a reply, via the management data area, from the slave station whose designated numerical value matches the primary temporary address.

[0012] In the identification number assignment step, a numerical value that has not been assigned to any other slave station is selected from among a number of different numerical values ​​prepared in advance corresponding to the number of slave stations, and assigned as an identification number via the management data area to each of the slave stations to which the unique primary temporary address has been assigned.

[0013] In the primary temporary address resetting step, the primary temporary address is reset to the slave station to which the overlapping primary temporary address has been set.

[0014] Then, after a different identification number is assigned to each of the slave stations, the identification numbers are sequentially designated via the management data area, and a slave station whose designated identification number matches the identification number assigned to itself transmits a label, which is associated with slave station identification information that can identify the slave station and which has been preset for the slave station, to the master station via the management data area.

[0015] Furthermore, after the parent station receives the label, an address indicating the start position in the control and monitoring data area of ​​the data area in the control and monitoring data area assigned to each of the child stations is set in each of the child stations using the identification number via the management data area, and is associated with the label.

[0016] In the slave station identification method according to the present invention, a numerical value that has not been assigned to any other slave station is selected from a number of different numerical values ​​prepared in advance, the number of which corresponds to the number of slave stations, and assigned as an identification number to each slave station to which a unique primary temporary address has been assigned. Therefore, even if the inquiry process, the duplication determination process, the identification number assignment process, and the primary temporary address resetting process are repeated many times, the identification number data assigned to each slave station does not exceed the transmittable data capacity. Therefore, even in situations where it is difficult to use conventional slave station identification methods, it is possible to use the identification number to assign an address to a label that is pre-assigned to the slave station and that is associated with slave station identification information that can identify the slave station. In other words, even in situations where it is difficult to use conventional slave station identification methods, it is possible to easily identify a slave station without requiring manual intervention, without having to consider the numerical representation of the address.

[0017] 1 is a system configuration diagram showing a schematic configuration of a control and monitoring signal transmission system to which a slave station identification method according to the present invention is applied; FIG. 2 is a system configuration diagram of a master station; FIG. 3 is a system configuration diagram of an input slave station; FIG. 4 is a system configuration diagram of an address setting processing means; FIG. 5 is a system configuration diagram of an output slave station; FIG. 6 is a schematic diagram showing a transmission procedure of a transmission signal; FIG. 7 is a time chart diagram of a transmission signal; and FIG. 8 is a diagram showing the flow of processing until labels are aggregated in a control side device.

[0018] An embodiment of the slave station identification method according to the present invention will be described with reference to Figures 1 to 8. Figure 1 is a configuration diagram of a control and monitoring signal transmission system to which the slave station identification method according to the present invention is applied. This control and monitoring signal transmission system is designed to centrally control a large number of devices and equipment located in a facility such as a factory using a control unit. As shown in Figure 1, the system comprises a master station 2 connected to a control unit 1 and common data signal lines DP and DN (hereinafter referred to as transmission lines), and a plurality of input slave stations 4, output slave stations 5, and input / output slave stations 6 located in the facility to be controlled and connected to the transmission lines. The type and number of slave stations connected to the transmission lines may be determined as appropriate depending on the state in which the system is used, etc. Also, for convenience of illustration, Figure 1 does not show all of the slave stations that make up the system.

[0019] The input unit 7 to which the input slave station 4 is connected, the output unit 8 to which the output slave station 5 is connected, and the input / output unit 9 to which the input / output slave station 6 is connected are devices located within the facility to be controlled.

[0020] Examples of the input unit 7 include, but are not limited to, a reed switch, a microswitch, a push button switch, a photoelectric switch, and various other sensors.

[0021] Examples of the output unit 8 include, but are not limited to, an actuator, a (stepping) motor, a solenoid, a solenoid valve, a relay, a thyristor, and a lamp.

[0022] The input / output unit 9 is a device that has the functions of both the input unit 7 and the output unit 8. For example, a device such as a temperature controller, timer, or counter can be used that has both the function of transmitting information to the master station 2 and the function of performing an output operation based on data transmitted from the master station 2.

[0023] The input unit 7 may be an input unit-integrated slave station 70 integrated with the input slave station 4. The output unit 8 may be an output unit-integrated slave station 80 integrated with the output slave station 5.

[0024] The control unit 1 includes a management and determination means 11 having a calculation function and an input / output unit 12. The management and determination means 11 receives data from the master station 2 via the input / output unit 12, and performs necessary calculations based on a program stored therein.

[0025] 3, the master station 2 is equipped with an output data section 21, a management data section 22, a timing generation section 23, a master station output section 24, a master station input section 25, an input data section 26, and a comparison / determination section 27. The master station 2 superimposes control data on a voltage clock signal having a predetermined period and duty ratio and transmits the superimposed control data, and also extracts monitoring data transmitted from the input slave station 4, the output slave station 5, and the input / output slave station 6 (hereinafter, when all of the input slave station 4, the output slave station 5, and the input / output slave station 6 are targeted, they are referred to as the slave stations 4, 5, and 6), and outputs the data to the input / output unit 12 of the control unit 1.

[0026] The output data section 21 transfers the data received from the control section 1 to the parent station output section 24 as serial data.

[0027] The management data unit 22 includes a nonvolatile memory 29 for storing a slave station information table. Based on the data received from the control unit 1 and the slave station information table, the management data unit 22 passes data required for issuing instructions to the slave stations in a management control data area (described later) as serial data to the master station output unit 24.

[0028] The storage means 29 also stores a number of different numerical values ​​corresponding to the number of slave stations. As will be described later, these numerical values ​​are assigned to each of the slave stations 4, 5, and 6 as an identification number.

[0029] The slave station information table includes addresses indicating the start positions of the data areas in the control and monitoring data areas assigned to each of the slave stations 4, 5, and 6.

[0030] As will be described later, after identification numbers are assigned to all of the slave stations 4, 5, and 6, the addresses and labels of the slave stations 4, 5, and 6 are set using those identification numbers. Then, in the management data section 22, an identification number table is created and stored according to a procedure that will be described later.

[0031] The timing generating unit 23 comprises an oscillator circuit (OSC) 31 and timing generating means 32 , and the timing generating means 32 generates a timing clock for this system based on the oscillator circuit (OSC) 31 and passes it to the parent station output unit 24 and parent station input unit 25 .

[0032] The parent station output unit 24 comprises a control data generating means 33 and a line driver 34. Based on the data received from the output data unit 21 and the timing clock received from the timing generating unit 23, the control data generating means 33 transmits a transmission signal on which control data is superimposed to the transmission line via the line driver 34.

[0033] In this embodiment, a voltage clock signal that transmits a timing clock using a change in voltage is used as the transmission clock signal, but there is no limitation on the method of transmitting the timing clock, and other methods suitable for the usage situation may be used.

[0034] The voltage clock signal is composed of a plurality of clock pulses. Each clock pulse has a period (hereinafter referred to as a "high period") during which the voltage level Ep is higher than the threshold value Est, as shown in the transmission signal in FIG. 7. In this embodiment, the voltage level Ep is set to +24 V.

[0035] The high period functions as a synchronous clock and a power supply voltage for communication, but the width and voltage level are not limited to those in this embodiment as long as they satisfy these requirements. They can be determined appropriately depending on the usage environment and usage state. For example, a negative voltage lower than the ground level may be maintained for a predetermined period of time.

[0036] Each clock pulse also has a data pulse which is used for data transmission between the master station 2 and the slave stations 4, 5 and 6.

[0037] In this embodiment, the data value of each data pulse is represented by a voltage level. However, the voltage level representing the data value can be determined appropriately depending on the usage environment and usage state. For example, it may be a negative voltage lower than the ground level.

[0038] In this embodiment, the data pulse indicates a data value by a voltage level lower than the voltage level Ep. A potential VL lower than the threshold Ect is a voltage level indicating a logical data value of "1," and a potential VM higher than the threshold Ect is a voltage level indicating a logical data value of "0." In this embodiment, the threshold Ect is set between 10 V and ground level (approximately 6 V), but there is no limit to its magnitude and it may be set according to the usage situation and environment. There is also no limit to the correspondence between the voltage level indicating the data value and the logical data value and it can be determined appropriately according to the usage environment and state.

[0039] In this embodiment, the data value is also indicated by the period of the data pulse. In this embodiment, if one period is defined as t0 from the falling edge of one high period to the falling edge of the next high period, a data pulse period of (3 / 4)t0 indicates logical data "1," and a data pulse period of (1 / 4)t0 indicates logical data "0." There is no limit to the length of these periods, and they may be determined appropriately as long as they correspond to the value of the control data input from the control unit 1.

[0040] The voltage clock signal is transmitted repeatedly from the master station 2, with one frame consisting of a series of high periods appearing for a predetermined number of times. As shown in Fig. 6, one frame contains a management data area and a control and monitoring data area.

[0041] Furthermore, a start signal ST, whose high period voltage level Ep is maintained for a longer period than the high period, is transmitted at the beginning of each frame to separate the frames. There is no limit to the length of the start signal ST as long as it can be distinguished from the high period, and it can be determined appropriately taking into account the conditions of use, etc.

[0042] A predetermined area within the control and monitoring data area is allocated to each of the slave stations 4, 5, and 6. Control data from the master station 2 to the output slave station 5 and input / output slave station 6 is superimposed on the area allocated to the target slave station, and monitoring data from the input slave station 4 and input / output slave station 6 to the master station 2 is superimposed on the area allocated to the slave station that transmits the monitoring data. In this way, the control and monitoring data area is used for sending and receiving regular data between the master station 2 and the slave stations 4, 5, and 6.

[0043] The management data area is used to transmit non-stationary data that cannot be transmitted using the control and monitoring data area. The primary temporary addresses or identification numbers for specifying the slave stations 4, 5, and 6, and the addresses set for the slave stations 4, 5, and 6 are transmitted using this management data area, and the details of the transmission procedure will be described later.

[0044] The parent station input unit 25 is made up of a line receiver 35 and a monitoring data extraction means 36. The line receiver 35 receives a voltage clock signal from the transmission line, shapes the waveform, and passes it to the monitoring data extraction means 36.

[0045] The monitoring data extraction means 36 obtains the timing for extracting the data value using the timing clock delivered from the timing generation unit 23, and extracts the data based on the voltage level of the voltage clock signal delivered from the line receiver 35. Then, it delivers the steady-state data DIO superimposed on the control / monitoring data area and the management data DEX superimposed on the management data area to the input data unit 26.

[0046] Furthermore, during address setting, which will be described later, the monitoring data extraction means 36 passes the management data DEX superimposed on the management data area to the comparison and judgment unit 27. The comparison and judgment unit 27 then performs a comparison and judgment using the element number and comparison and judgment data, which will be described later, and passes the judgment result of match or mismatch to the management data unit 22.

[0047] The input data section 26 converts the serial input data received from the monitoring data extraction means 36 into parallel data, and outputs it to the input unit 12 of the control section 1 as IO monitoring data and management monitoring data.

[0048] <Configuration of Input Slave Station> As shown in FIG. 3, the input slave station 4 includes a slave station input unit 40 that executes the main arithmetic processing, and a slave station line receiver 51 and a slave station line driver 52 that are arranged between the slave station input unit 40 and the transmission line. The input slave station 4 receives a voltage clock signal from the transmission line via the slave station line receiver 51, and transmits monitoring data via the slave station line driver 52.

[0049] The slave station input unit 40 has a transmission / reception means 41, a management control data extraction means 42, an address extraction means 43, a profile data storage means 44, a management monitoring data transmission means 45, an input means 46, a monitoring data transmission means 47, a management control instruction determination means 48, an address setting processing means 49 and a communication means 58.

[0050] The input slave station 4 of this embodiment includes an MCU, which is a microcomputer control unit, as an internal circuit, and this MCU functions as a slave station input section 40 .

[0051] The slave station line receiver 51 receives the voltage clock signal from the transmission line, shapes the waveform, and passes it to the transmission / reception means 41 .

[0052] The transmission / reception means 41 judges whether the voltage level corresponds to the threshold value Est or threshold value Ect, and passes the voltage level of the voltage clock signal passed from the slave station line receiver 51 to the management control data extraction means 42, address extraction means 43, and management monitoring data transmission means 45.

[0053] The management control data extraction means 42 identifies the start signal ST based on the voltage level of the voltage clock signal. Then, starting from the timing when the start signal ST ends (in this embodiment, the falling edge), it extracts management data based on the voltage level of the management data area. The extracted management data is then passed to the management control instruction determination means 48.

[0054] The address extraction means 43 identifies the start signal ST based on the voltage level of the voltage clock signal, and counts the high period starting from the timing when the start signal ST ends (in this embodiment, the falling edge).Then, it obtains the timing when this count value matches the local station address data set by the address setting means 44. This timing is the timing when the area assigned to the local station (hereinafter referred to as the "local station area") in the control and monitoring data area starts (hereinafter referred to as the "local station area start timing").

[0055] Then, the address extraction means 43, which has obtained the timing to start the own station area, activates the monitoring data transmission means 47. If the own station area contains multiple data pulses, the monitoring data transmission means 47 is activated until the end of the own station area.

[0056] The profile data storage means 44 stores profile data indicating the device characteristics of the local station, such as the type of input / output, the number of occupied points (occupied addresses) in the control / monitoring data area, etc. The profile data storage means 44 also stores a primary temporary address, an identification number, and a label associated with slave station identification information that can identify the slave station.

[0057] The management / monitoring data transmitting means 45 determines the start signal ST based on the voltage level of the transmission signal, and outputs the monitoring data as needed in the management data area starting from the timing when the start signal ST ends.

[0058] In this embodiment, in the primary temporary address confirmation process described later, comparison judgment data (comparison data and its element number) is delivered from the address setting processing means 49. In the profile data transmission process described later, the profile data of the own station is delivered from the profile data storage means 44.

[0059] If a response is requested from the master station 2 in the normal state after address setting has been completed, the response is transmitted only when the data to be transmitted to the master station 2 has been handed over from the processing means that responds to requests from the management control instruction determination means 48. In Fig. 3, the address setting processing means 49 and the profile data storage means 44 are shown as the processing means that responds to requests from the management control instruction determination means 48 when setting an address, but the processing means that responds to requests from the management control instruction determination means 48 in the normal state is not shown.

[0060] The input means 46 transfers data based on the input from the input unit 7 to the monitoring data transmission means 47 .

[0061] When the monitoring data transmitting means 47 is validated by the address extracting means 43 , it outputs the data passed from the input means 46 as monitoring data via the slave station line driver 52 .

[0062] The management control instruction determination means 48 executes appropriate output processing based on the management control data handed over from the management control data extraction means 42. In this embodiment, it outputs an instruction signal to execute primary temporary address generation processing and primary temporary address confirmation processing to the address setting processing means 49. Furthermore, when executing identification number determination processing and address determination processing, it passes data addressed to its own station, which is included in the management control data, to the profile data storage means 44. Furthermore, when executing profile data transmission processing, it outputs a signal instructing data transmission to the profile data storage means 44.

[0063] <Primary temporary address generation process> As shown in Fig. 4, the address setting process means 49 is made up of address generation means 53, comparison judgment data generation means 54, and random number generation means 55. When the management control instruction determination means 48 selects execution of the primary temporary address generation process, an instruction signal is output to the address generation means 53. The address generation means 53 selects one of a predetermined number of numerical values ​​as a primary temporary address based on the random number delivered from the random number generation means 55. The selected primary temporary address is delivered to and stored in the profile data storage means 44. The primary temporary address stored in the profile data storage means 44 is delivered to the management control data extraction means 42 in response to a request from the management control data extraction means 42.

[0064] <Primary tentative address verification process> When the management control instruction determination means 48 selects execution of the primary tentative address verification process, it outputs an instruction signal to the comparison judgment data generation means 54. The comparison judgment data generation means 54 selects one of a predetermined number of numerical values ​​as an original number based on the random number delivered from the random number generation means 55. The comparison judgment data generation means 54 also generates comparison matching data by converting the original number in accordance with a predetermined rule. The original number and the comparison matching data are then delivered to the management monitoring data transmission means 45.

[0065] <Identification Number Confirmation Process> When the management control instruction determination means 48 selects to execute the identification number confirmation process, the identification number data transmitted to the local station is output to the profile data storage means 44. The profile data storage means 44 receives this data and stores it as an identification number. The identification number stored in the profile data storage means 44 is passed to the management control data extraction means 42 in response to a request from the management control data extraction means 42.

[0066] <Profile Data Output Processing> When the management control instruction determination means 48 selects execution of the profile data output processing, a signal instructing output of profile data is output to the profile data storage means 44. In response to this, the profile data storage means 44 passes the profile data and label to the management monitoring data transmission means 45.

[0067] <Address Confirmation Process> When the management control instruction determination means 48 selects execution of the address confirmation process, the address data transmitted to the local station is output to the profile data storage means 44. The profile data storage means 44 receives this data and stores it as an address. The address is validated by restarting the system or by some other means after the address setting process is completed. After the address is validated, the profile data storage means 44 passes the address to the respective requesting means in response to requests from the management control data extraction means 42 and the address extraction means 43.

[0068] In this embodiment, the random number generating means 55 is always in operation, but it may be operated in response to an instruction signal output from the management control instruction determining means 48. The random number generating algorithm may be one that is optimal for the operating conditions.

[0069] Furthermore, when a response of some kind is requested from the parent station 2 in the normal state after the address setting is completed, the management control instruction determination means 48 outputs a signal according to the processing to a processing means (not shown) for executing processing according to the purpose of management control.

[0070] The communication means 58 is connected for communication with an external terminal 59 that is separate from the slave station 4, and when setting data is handed over from the external terminal 59, it passes this data to the profile data storage means 44. When data is handed over from the communication means 58, the profile data storage means 44 stores this data.

[0071] Furthermore, when a request for data delivery is received from the external terminal 59, the communication means 58 extracts the relevant data from the profile data storage means 44 and delivers it to the external terminal 59. The data delivered from the communication means 58 to the external terminal 59 is displayed on a display unit provided in the external terminal 59.

[0072] In this embodiment, the label is set via the communication means 58 and the external terminal 59 .

[0073] <Configuration of Output Slave Station> As shown in Fig. 5, the output slave station 5 comprises a slave station output unit 50 that performs main arithmetic processing, and a slave station line receiver 51 and a slave station line driver 52 that are arranged between the slave station output unit 50 and the transmission line. The output slave station 5 receives transmission signals from the transmission line via the slave station line receiver 51, outputs information based on control data to the output unit 8, and operates or stops the output unit 8. Furthermore, when data transmission and reception using the management data area is required, monitoring data is transmitted via the slave station line driver 52. Note that in Fig. 5, parts that are substantially the same as those in the input slave station 4 are designated by the same reference numerals, and their description will be simplified or omitted.

[0074] The slave station output unit 50 has a transmission / reception means 41, a management control data extraction means 42, an address extraction means 43, a profile data storage means 44, a management monitoring data transmission means 45, a management control instruction determination means 48, an address setting processing means 49, a control data extraction means 56, an output means 57, and a communication means 58.

[0075] Like the input slave station 4, the output slave station 5 of this embodiment also has an MCU, which is a microcomputer control unit, as an internal circuit, and this MCU functions as a slave station output section 50.

[0076] When the address extraction means 43 of the output slave station 5 obtains the start timing of its own station area, it activates the control data extraction means 56. If the own station area includes multiple data pulses, it activates the control data extraction means 56 at each data pulse that appears until the own station area ends.

[0077] When the control data extraction means 56 is enabled by the address extraction means 43 , it extracts control data based on the voltage level of the voltage clock signal delivered from the transmission / reception means 41 and delivers it to the output means 57 .

[0078] The output means 57 outputs information based on the control data passed from the control data extraction means 56 to the output unit 8, and activates or stops the output unit 8.

[0079] <Configuration of Input / Output Substation> The input / output substation 6 has the functions of both the input substation 4 and the output substation 5, and has a substation input / output section that combines the configuration of both the substation input section 40 and the substation output section 50. However, since the configuration is essentially the same as the substation input section 40 and the substation output section 50, illustration and description thereof will be omitted.

[0080] Next, with reference to Figure 8, we will explain how to set addresses for the slave stations 4, 5, and 6. First, the master station 2 issues a broadcast command to all slave stations 4, 5, and 6 to instruct them to set primary temporary addresses. Upon receiving this command, the slave stations 4, 5, and 6 execute the primary temporary address generation process described above, and one number selected from a predetermined number of numbers based on a random number is set as the primary temporary address (step 1 in Figure 8).

[0081] Next, the master station 2 sequentially specifies all of a predetermined number of values ​​that can be set as primary temporary addresses using the management control data area (step 2 in FIG. 8). When the slave stations 4, 5, and 6 receive this, if the primary temporary addresses set in their own stations match the values ​​specified by the master station 2, they execute the primary temporary address confirmation process described above. Then, the original number and comparison data are output to the management monitoring data area (step 3 in FIG. 8).

[0082] In the master station 2 that has received the element number and the comparison data, the comparison and judgment unit 27 converts the element number in the same way as the slave stations 4, 5, and 6 to generate comparison and judgment data, and performs comparison and judgment with the comparison and judgment data received from the slave stations 4, 5, and 6. If the two data match, data indicating that there is no duplication is passed from the comparison and judgment unit 27 to the management data unit 22 (step 3 in FIG. 8).

[0083] If there is an overlap, different elements and different comparison data are transmitted from the multiple slave stations 4, 5, and 6, and the elements and comparison data received by the master station 2 are a superposition of these. Therefore, the elements and comparison data received by the master station 2 do not conform to a predetermined rule, and the comparison data generated by the comparison and judgment unit 27 of the master station 2 does not match the comparison and judgment data received from the slave stations 4, 5, and 6. In other words, if the two pieces of data do not match, this means that there is an overlap. Therefore, if the two pieces of data do not match, data indicating that there is an overlap is passed from the comparison and judgment unit 27 to the management data unit 22 (step 3 in FIG. 8).

[0084] If a value that is not set as a temporary temporary address in any of the slave stations 4, 5, and 6 is specified, the original number is not transmitted from any of the slave stations 4, 5, and 6. Therefore, in this embodiment, if the original number received by the master station 2 is 0, it is determined that none of the slave stations 4, 5, and 6 has that value set as a temporary temporary address, and no comparison is performed.

[0085] If there is no overlap, the management data section 22 of the master station 2 selects a number that has not yet been assigned to any of the slave stations 4, 5, or 6 from among the pre-prepared numbers stored in the storage means 29, and adds it to the identification number table as an assigned identification number. It also passes this number to the master station output section 24, and transmits this identification number via the management data area to the primary temporary address that has been determined to be free of overlaps (step 4 in FIG. 8).

[0086] If the primary temporary address set in each of the slave stations 4, 5, and 6 that received this message matches the value set in the master station 2, the above-mentioned identification number determination process is executed (step 4 in FIG. 8).

[0087] On the other hand, for duplicate primary temporary addresses, a primary temporary address reset instruction is issued. When the primary temporary addresses set in the slave stations 4, 5, and 6 receive this instruction and match the values ​​specified by the master station 2, the slave stations 4, 5, and 6 execute the primary temporary address generation process described above, and reset the primary temporary address to one selected from a predetermined number of values ​​based on a random number (step 5 in FIG. 8).

[0088] When the primary temporary addresses of the slave stations 4, 5, and 6 whose previously set primary temporary addresses were duplicated are reset, the presence or absence of a duplicate is determined for the reset primary temporary addresses using the same procedure as described above. Then, for the slave stations 4, 5, and 6 for which a unique primary temporary address has been set, a numerical value that has not yet been assigned to any of the slave stations 4, 5, and 6 is selected from pre-prepared numerical values ​​and assigned as an identification number. Furthermore, for the slave stations 4, 5, and 6 for which a duplicate primary temporary address has been set, the primary temporary addresses are reset again, and the presence or absence of a duplicate is determined.

[0089] The process of setting a primary temporary address, determining whether there is an address overlap, and determining the identification number is repeated until all the prepared numerical values ​​for assigning identification numbers have been assigned as identification numbers (step 6 in FIG. 8).

[0090] Once all of the slave stations 4, 5, and 6 have been assigned identification numbers, the master station 2 sequentially assigns all of the identification numbers and collects the profile data and labels of each of the slave stations 4, 5, and 6. An identification number table is then created in which the profile data and labels are associated with the identification numbers (step 7 in FIG. 8).

[0091] Once the identification number table is complete, addresses reflecting the occupied points (occupied addresses) are assigned to all slave stations 4, 5, and 6 based on the slave station information table and profile data of the identification number table stored in the management data section 22 of the master station 2 (step 8 in FIG. 8).

[0092] The addresses assigned to all the slave stations 4, 5, and 6 are set from the master station 2 to all the slave stations 4, 5, and 6 via a transmission line using the identification numbers. In this embodiment, the management control data area is used to sequentially specify the identification numbers, and the addresses associated with the specified identification numbers are transmitted. When the slave stations 4, 5, and 6 receive this information, if the identification numbers set in their own stations match the numbers specified by the master station 2, the address determination process described above is performed. The addresses are then set in the slave stations 4, 5, and 6 (step 9 in FIG. 8).

[0093] The addresses set in all the slave stations 4, 5, and 6 are validated by a setting value validation process (step 10 in FIG. 8). In this embodiment, the addresses are validated by restarting the system after the address setting process (steps 1 to 9 in FIG. 8) is complete. However, there are no restrictions on the validation method, and it can be determined appropriately depending on the usage and design conditions. For example, a broadcast command may be sent from the master station 2 to all the slave stations 4, 5, and 6.

[0094] In this embodiment, addresses are assigned by the management data unit 22 of the master station 2, but there are no restrictions on the procedure for assigning addresses. For example, if there is no slave station information table, addresses may be assigned based on an identification number table while taking into account the system design.

[0095] In addition, although the addresses in this embodiment are assigned based on the profile data of the slave stations 4, 5, and 6, if programming using labels is performed, the addresses may be assigned based on the labels.

[0096] The primary temporary address may be set by employing any other method that is not based on random numbers, as long as one of a predetermined number of numerical values ​​is set.

[0097] According to this embodiment, the slave stations 4, 5, and 6 can be identified using labels aggregated in the master station 2, which is the control device.

[0098] The label is associated with slave station identification information that can identify the slave stations 4, 5, and 6. The slave station identification information includes location information that identifies the locations where the slave stations 4, 5, and 6 are installed, the input / output types of the slave stations 4, 5, and 6, and the intended use of the slave stations 4, 5, and 6. Any one of these pieces of information or a combination of two or more pieces of information may be used. For example, OL1, OL2, and the like may be created by combining the letter O, which indicates an output device as the input / output type, the letter L, which indicates a lighting device as the intended use, and the number of the room where the slave stations 4, 5, and 6 are installed as the location information.

[0099] The labels must be set before the address setting process is executed, but there are no limitations on the setting method. As in this embodiment, the labels may be set by providing an input operation device in the slave stations 4, 5, and 6, without using an external terminal 59 separate from the slave stations 4, 5, and 6. The labels may also be set on-site after the slave stations 4, 5, and 6 are installed, or before they are installed. In either case, it is preferable to display the contents of the labels in a visible state on the slave stations 4, 5, and 6 themselves or near the locations where the slave stations 4, 5, and 6 are installed.

[0100] REFERENCE SIGNS LIST 1 Control unit 2 Master station 4 Input slave station 5 Output slave station 6 Input / output slave station 7 Input unit 8 Output unit 9 Input / output unit 11 Management judgment means 12 Input / output unit 21 Output data unit 22 Management data unit 23 Timing generation unit 24 Master station output unit 25 Master station input unit 26 Input data unit 27 Comparison judgment unit 29 Storage means 31 Oscillator circuit (OSC) 32 Timing generation means 33 Control data generation means 34 Line driver 35 Supervisory signal detection means 36 Supervisory data extraction means 40 Slave station input unit 41 Transmission / reception means 42 Management control data extraction means 43 Address extraction means 44 Profile data storage means 45 Management / supervisory data transmission means 46 Input means 47 Supervisory data transmission means 48 Management control instruction judgment means 49 Address setting processing means 50 Slave station output unit 51 Slave station line receiver 52 Slave station line driver 53 Address generating means 54 Comparison judgment data generating means 55 Random number generating means 56 Control data extracting means 57 Output means 58 Communication means 59 External terminal

Claims

1. A control and monitoring signal transmission system comprising a master station that exchanges data with a control unit, and a plurality of slave stations that exchange data with the master station via a common transmission line in a transmission synchronization manner. Data exchange between the master station and the slave stations is performed by superimposing data on frames repeatedly transmitted from the master station. The frames are time-division multiplexed, and a control and monitoring data area in which the data transmission direction is determined and allocated to each of the slave stations, and a management data area for data exchange with all of the slave stations separately from the control and monitoring data area are provided. In this system, one of a predetermined number of numerical values is set as a primary temporary address for each slave station. An inquiry process is executed in which all numerical values that could be set as the primary temporary address are sequentially specified from the master station via the management data area, and an inquiry to the slave stations is performed. A duplication determination process determines the presence or absence of duplication of the primary temporary address based on a reply to the inquiry via the management data area from the slave station for which the specified numerical value matches the primary temporary address. An identification number assignment process selects, for each slave station for which a non-duplicated primary temporary address is set, a numerical value that has not been assigned to other slave stations from among all of a plurality of previously prepared different numerical values corresponding to the number of slave stations, and assigns it as an identification number via the management data area. A primary temporary address re-setting process in which the primary temporary address is re-set for the slave station for which a duplicated primary temporary address is set is repeated until all of the previously prepared numerical values are assigned as identification numbers. After different identification numbers are assigned to each slave station, the identification numbers are sequentially specified via the management data area, and from the slave station for which the specified identification number matches the identification number assigned to its own station, a label pre-set for the slave station and associated with slave station identification information that can identify the slave station is transmitted to the master station via the management data area. After the master station receives the label, an address indicating the start position in the control and monitoring data area of the data area in the control and monitoring data area to be allocated to each of the slave stations is set for each of the slave stations using the identification number via the management data area and associated with the label. A method for identifying slave stations, characterized in that it is associated with the label.

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