摘要:
A method is based on a communication- and data network for the automatic time synchronization of field devices, namely fill-level measuring devices and pressure measuring devices as well as field-device control units. The method comprises the steps of: determining a current time value by the field device or by the field-device control unit, and providing a desired value in a central server. Furthermore, the method comprises the following steps: comparing the current time value with the desired value, and setting the current time value to the desired value when the desired value differs from the current time value by more than a predetermined threshold value.
摘要:
A programmable data link module (32) for use in a time division multiplexing control system (30) having a plurality of modules interconnected by a bus (40) for passing control signals between data link modules on a serial multiplex basis. Each module includes an integrated circuit (80) having signal conditioning circuits (180, 186 and 188) including a programmable hysteresis circuit (126), a power on reset delay circuit (190), a safety input inhibit circuit (220), a clock loss detect circuit (240), a safety output protection circuit (262), a data verifier (260), a polarity selector for a third output terminal (350), an input synchronizer (182 and 184), a combined mode/sync output terminal (110), a multiplex clock output terminal (108), a programming circuit (232) for accepting programming over the clock bus (44) and data bus (46), input/output word extender circuits (104, 106), a high voltage protection circuit (420) including a transistor (600) and a data bus integrity checker (630).
摘要:
A programmable data link module (32) for use in a time division multiplexing control system (30) having a plurality of modules interconnected by a bus (40) for passing control signals between data link modules on a serial multiplex basis. Each module includes an integrated circuit (80) having signal conditioning circuits (180, 186 and 188) including a programmable hysteresis circuit (126), a power on reset delay circuit (190), a safety input inhibit circuit (220), a clock loss detect circuit (240), a safety output protection circuit (262), a data verifier (260), a polarity selector for a third output terminal (350), an input synchronizer (182 and 184), a combined mode/sync output terminal (110), a multiplex clock output terminal (108), a programing circuit (232) for accepting programming over the clock bus (44) and data bus (46), input/output word extender circuits (104, 106), a high voltage protection circuit (420) including a transistor (600) and a data bus integrity checker (630).
摘要:
A synchronization method, a control system and a slave unit for the time synchronization of at least two slave units, in which the slave units and the master unit are connected by two signal lines. A signal transmitted by the master unit returns to the master unit after passing through all the slave units. Two independent counters are provided in each slave unit, these counters being activated by reception of a reference signal transmitted by the master unit. The first time counter counts the time since the receipt of the reference signal via the first signal line and the second time counter counts the time since the receipt of the reference signal via the second signal line. The counter contents are read out as soon as the sum of the counter contents reaches a signal throughput time transmitted previously by the master unit.
摘要:
A synchronization method, a control system and a slave unit for the time synchronization of at least two slave units, in which the slave units and the master unit are connected by two signal lines. A signal transmitted by the master unit returns to the master unit after passing through all the slave units. Two independent counters are provided in each slave unit, these counters being activated by reception of a reference signal transmitted by the master unit. The first time counter counts the time since the receipt of the reference signal via the first signal line and the second time counter counts the time since the receipt of the reference signal via the second signal line. The counter contents are read out as soon as the sum of the counter contents reaches a signal throughput time transmitted previously by the master unit.
摘要:
The invention relates to a synchronous clocked communication system, for example a distributed automation system, the stations of which can be arbitrary automation components and which are coupled to one another via a data network (1). Using the disclosed method for integrating decentralized input/output modules (2, 3), these decentralized input/output modules (2, 3) can be linked into the synchronous clocked communication system in such a manner that they can use their characteristics unrestrictedly. Thus, in particular, the detection of input signals and the output of output signals is possible in a deterministic and synchronous manner in the decentralized input/output modules 2, 3. In addition, the disclosed method enables input signals to be detected with an accuracy of less than the length of one communication cycle of the communication system and to support the switching of output signals in smaller time granularities than the length of one communication cycle which, in particular, finds use, e.g. for switching cams. In addition, the invention provides for synchronization for actual-value detections and nominal-value outputs of the most varied types of automation components such as, e.g. decentralized input/output modules (2, 3) and digital drives (4, 5, 6). All possible bus systems such as, e.g. field bus, professional field bus, Ethernet, industrial Ethernet, FireWire or also bus systems internal to a PC (PCI) etc. are conceivable as the data network (1) of the communication system.
摘要:
A programmable data link module is used on a time division multiplex data bus. The module is functional as an input device, an output device, or both as an input and output device. It can receive data from the data bus during the selected time slot for a selected number of frames to control output devices connected to it. The data link module includes an input circuit for generating a data output signal data to the data bus in response to the input signals from an input device coupled to the module. The input circuit includes a programmable input communication mode selector, allowing the data bus and the data link module to function with or without a host computer. The mode selector provides simplex or duplex.
摘要:
A programmable data link module is used on a time division multiplex data bus. The module is functional as an input device, an output device, or both as an input or output device. It can receive data from the data bus during a selected time slot for selected number of frames to control output devices connected to it. The data link module includes an input circuit for generating a data output signal data to the data bus in response to input signals from in input device coupled to the module. The input circuit includes a programmable input communication mode selector, allowing the data bus and the data link module to function with or without a host computer. The mode selector provides simplex or duplex.
摘要:
A programmable data link module for use with a time division multiplex data bus includes an input and a high voltage protection circuit to prevent outputting of data to the data bus under several different operation conditions. These include programming of the data link module and verification of the programming. The data link module also inhibits the outputting of data signals to the data bus in response to changes of the input signals from a local input device until the power to the data link module has stabilized for a preselected period of time. The high voltage protection circuit protects the data link module from excessive overvoltage from other devices connected to the data bus.
摘要:
A programmable data link module is used on a time division multiplex data bus having a repetitive time frame, each time frame having a plurality of time slots. The module receives data from the data bus during a selected time slot for a selected number of frames. The data link module includes a data verifier for storing the received data during the selected frames and inhibits outputting of data signals to the data bus until a repetitive occurrence of the received data over the selected number of frames has been verified.