Abstract: A counter variable search unit (121) finds a counter variable from a control program. A remainder operation search unit (122) finds a remainder operation on the counter variable from the control program. A branch instruction search unit (123) finds a conditional branch instruction on a remainder of the remainder operation from the control program. An input/output variable extraction unit (124) extracts an input/output variable from a branch destination block of the conditional branch instruction. A target equipment identification unit (125) identifies target equipment to or from which a value of the extracted input/output variable is input or output. A communication period determination unit (126) determines a communication period of the identified target equipment.

Abstract: A production line control device includes: an input unit to receive user identification information and product identification information; an authentication unit to authenticate the user identification information; an acquisition unit to acquire a production condition for producing a product associated with the product identification information and the user identification information; a modification unit to generate a modified production condition by modifying the production condition acquired by the acquisition unit; a supply instruction unit to instruct a material supply device corresponding to the modified production condition to supply a material corresponding to the modified production condition; a processing instruction unit to instruct a processing device corresponding to the modified production condition to process a material corresponding to the modified production condition; and a storage instruction unit to instruct a product storage device corresponding to the modified production condition to st

Abstract: A slave station (102), in an initial state, puts a relay device to a relay-disconnected status and transmits an assignment request requesting address assignment for the own slave station. A master station (101), in response to an assignment request from an adjacent slave station (102), performs address assignment for the slave station (102), and transmits an assignment request response containing an assigned address. The slave station (102), upon reception of the assignment request response, stores the address contained in the assignment request response to a memory, and puts the relay device to a relay status. If the slave station (102) receives the assignment request after address assignment for the slave station is completed, the slave station performs address assignment for a slave station being a sender of the assignment request instead of relaying the assignment request, and transmits an assignment request response containing an assigned address.

Abstract: An allocation device (100) includes an allocation consideration unit (150) to find a value obtained by arithmetic operation on a base, the value being a natural number equal to or less than a value obtained by dividing each of a plurality of communication intervals by a value equal to or more than an evaluation cycle, as a plurality of evaluation frequencies respectively corresponding to the plurality of communication intervals, to set a plurality of communication frequencies respectively corresponding to the plurality of communication intervals as once in a cycle indicated by each of the plurality of evaluation frequencies, and to determine a communication plan, the communication plan indicating a period in which a communication of each of the plurality of communication types is performed, by allocating a cycle number identifying a cycle to any one communication type of a plurality of communication types, thereby performing an allocation process.

Abstract: A communication system (100) includes communication device (1) to communication device (9). Communication device (1) to communication device (9) select a first representative device that represents a same domain. Communication device (3) is selected from domain D (1), communication device (6) is selected from domain D (2), and communication device (9) is selected from domain D (3). For communication device (3), communication device (6), and communication device (9) selected from each domain, communication device (3) sets to communication device (3), communication device (6) sets to communication device (6), and communication device (9) sets to communication device (9), domain D (0) as a common domain to which communication device (3), communication device (6), and communication device (9) belong. Communication device (3), communication device (6), and communication device (9) select communication device (9) as a network grandmaster that is a second representative device that represents domain D (0).

Abstract: A list distribution station of a communication station includes processing circuitry to record, in a memory, a grand master list containing a station code of a grand master and a station code of a communication station synchronized with the grand master, and receive a priority notification frame which contains, as a sender station code, a station code of a present grand master in the communication system. The processing circuitry is further included to decide, when notified of the station code of the present grand master, whether or not to update the grand master list based on the notified station code of the present grand master and the grand master list, and upon having decided to update the grand master list, to update the station code of the present grand master station on the grand master list with the notified station code of the present grand master station.

Abstract: A list distribution station of a communication station includes processing circuitry to record, in a memory, a grand master list containing a station code of a grand master and a station code of a communication station synchronized with the grand master, and receive a priority notification frame which contains, as a sender station code, a station code of a present grand master in the communication system. The processing circuitry is further included to decide, when notified of the station code of the present grand master, whether or not to update the grand master list based on the notified station code of the present grand master and the grand master list, and upon having decided to update the grand master list, to update the station code of the present grand master station on the grand master list with the notified station code of the present grand master station.

Abstract: A network system constituted by a communication device performing communication of a first communication protocol for periodically transmitting data requiring low-delay transmission, a communication device performing communication of a second communication protocol for non-periodically transmitting data requiring low-delay transmission, and a communication device performing communication of a third communication protocol for transmitting data that does not require low-delay transmission, wherein a period in which transmission with the first protocol is permitted, a period in which transmission with the second protocol is permitted, and a period in which transmission with the third protocol is permitted are allocated, and each communication device transmits data in a period in which transmission with the protocol supported by the communication device is permitted, and transfers data received from another communication device in a period in which transmission with a protocol supported by a data transmission sou

Abstract: A communication system includes a plurality of high-performance communication devices located in a first communication network and having a first communication processing performance, and a low-performance communication device located in a second communication network and having a second communication processing performance. A high-performance communication device, which is one of the high-performance communication devices and is located at a boundary of connection with the low-performance communication device, restricts relay of a broadcast frame transmitted and received in the first communication network to the second communication network.

Abstract: A communication system includes a plurality of high-performance communication devices located in a first communication network and having a first communication processing performance, and a low-performance communication device located in a second communication network and having a second communication processing performance. A high-performance communication device, which is one of the high-performance communication devices and is located at a boundary of connection with the low-performance communication device, restricts relay of a broadcast frame transmitted and received in the first communication network to the second communication network.

Abstract: A network system constituted by a communication device performing communication of a first communication protocol for periodically transmitting data requiring low-delay transmission, a communication device performing communication of a second communication protocol for non-periodically transmitting data requiring low-delay transmission, and a communication device performing communication of a third communication protocol for transmitting data that does not require low-delay transmission, wherein a period in which transmission with the first protocol is permitted, a period in which transmission with the second protocol is permitted, and a period in which transmission with the third protocol is permitted are allocated, and each communication device transmits data in a period in which transmission with the protocol supported by the communication device is permitted, and transfers data received from another communication device in a period in which transmission with a protocol supported by a data transmission sou

Abstract: A communication system includes: a first communication device that transmits a plurality of frames at a transmission time interval shorter than a time required for transmitting a minimum frame; and a second communication device that performs timing synchronization with the first communication device on the basis of the plurality of frames when a reception time interval of the plurality of frames received is equal to the transmission time interval.

Abstract: A communication device for forming a communication network, which generates a search frame, which is a frame for searching for a communication path in setting a communication path to/from another communication device, transmits the search frame to other communication devices, and selects a communication path with a shortest delay time to each of the other communication devices on the basis of information in the search frame having passed through other communication devices and returned to the communication device.

Abstract: Even if the propagation time interval of a sync signal is not constant, an accurate correction parameter is calculated, so that a corrected time point synchronized with a main clock device is obtained. A main transmission time point storage part stores respective main transmission time points at which a main device has transmitted a plurality of main sync signals and which are measured using a main clock device. A subordinate reception time point storage part stores respective subordinate reception time points at which a subordinate device has received the plurality of main sync signals and which are measured using a subordinate clock device. A speed ratio calculation part calculates a speed ratio of a ticking time speed of the main clock device to a ticking time speed of the subordinate clock device, based on a main transmission mean time point being a mean of the main transmission time points and a subordinate reception mean time point being a mean of the subordinate reception time points.

Abstract: A communication device which has a frame reception unit to separate a frame received from one device into a relay sub-payload that is not addressed to the device itself, and an own-device addressed sub-payload that is addressed to the device itself, an error detection unit to perform error detection based on the error-detection code within the own-device addressed sub-payload, a relay sub-payload storage unit to store the relay sub-payload, a communication-start notification unit to notify a communication-start timing to start communication simultaneously with other devices, and a frame transmission unit to start transmitting to another device the frame including a preamble and the relay sub-payload upon being notified of the communication-start timing, and to add the relay sub-payload to an end of the frame currently being transmitted, so as to continue transmission of the frame, when the relay sub-payload is stored in the relay sub-payload storage unit.

Abstract: Even if the propagation time interval of a sync signal is not constant, an accurate correction parameter is calculated, so that a corrected time point synchronized with a main clock device is obtained. A main transmission time point storage part stores respective main transmission time points at which a main device has transmitted a plurality of main sync signals and which are measured using a main clock device. A subordinate reception time point storage part stores respective subordinate reception time points at which a subordinate device has received the plurality of main sync signals and which are measured using a subordinate clock device. A speed ratio calculation part calculates a speed ratio of a ticking time speed of the main clock device to a ticking time speed of the subordinate clock device, based on a main transmission mean time point being a mean of the main transmission time points and a subordinate reception mean time point being a mean of the subordinate reception time points.

Abstract: Even if the propagation time interval of a sync signal is not constant, an accurate correction parameter is calculated, so that a corrected time point synchronized with a main clock device is obtained. A main transmission time point storage part stores respective main transmission time points at which a main device has transmitted a plurality of main sync signals and which are measured using a main clock device. A subordinate reception time point storage part stores respective subordinate reception time points at which a subordinate device has received the plurality of main sync signals and which are measured using a subordinate clock device. A speed ratio calculation part calculates a speed ratio of a ticking time speed of the main clock device to a ticking time speed of the subordinate clock device, based on a main transmission mean time point being a mean of the main transmission time points and a subordinate reception mean time point being a mean of the subordinate reception time points.

Abstract: A communication system includes: a first communication device that transmits a plurality of frames at a transmission time interval shorter than a time required for transmitting a minimum frame; and a second communication device that performs timing synchronization with the first communication device on the basis of the plurality of frames when a reception time interval of the plurality of frames received is equal to the transmission time interval.

Abstract: A synchronous frame reception unit receives a synchronous frame describing a reference value for time synchronization with a management apparatus which is transmitted repeatedly from the management apparatus. A propagation delay computation unit computes, each time when the synchronous frame is received, a propagation delay of the synchronous frame. A propagation delay time period computation unit computes, each time when the propagation delay is computed, a propagation delay time period by adding a target value of a synchronous accuracy to the propagation delay. A propagation delays computation unit operates a logical OR operation of M pieces of propagation delay time periods computed for M pieces of synchronous frames which precede a latest synchronous frame.

Abstract: To include a frame reception unit to separate a frame received from one device into a relay sub-payload that is not addressed to a device of its own, and an own-device addressed sub-payload that is addressed to a device of its own, an error detection unit to perform error detection based on the error-detection code within the own-device addressed sub-payload, a relay sub-payload storage unit to store therein the relay sub-payload, a communication-start notification unit to notify a communication-start timing to start communication simultaneously with other devices, and a frame transmission unit to start transmitting to another device the frame including a preamble and the relay sub-payload upon being notified of the communication-start timing, when the frame is not being transmitted, and to add the relay sub-payload to an end of the frame being transmitted, so as to continue transmission of the frame, when the relay sub-payload is stored in the relay sub-payload storage unit while the frame is being transmitt