摘要:
The invention refers to a method for monitoring a communication media access schedule of a communication controller (5) of a communication system (1) by means of a bus guardian (6). The communication system (1) comprises a communication media (2) and nodes (3) connected to the communication media (2). Each node (3) comprises a communication controller (5) and a bus guardian (6) assigned to the communication controller (5). Messages are transmitted among the nodes (3) across the communication media (2) based on a cyclic time triggered communication media access scheme. In order to provide a mechanism which allows the bus guardian (6) to monitor the communication media access scheme of the communication controller (5) even during startup of the communication it is suggested, that the bus guardian (6) has a priori knowledge about possible deviations from the communication media access schedule during startup of the communication and that the bus guardian (6) during startup makes use of the a priori knowledge to distinguish between an allowed deviation and a forbidden deviation caused by a failure of the communication controller (5).
摘要:
A data communication network may, include a first sub-network and a second sub-network. The first sub-network may include two or more two master clocks, and a synchronization system connected to the master clocks. The synchronization system may, for determine a time-base for the master clocks and control the master clocks based on the determined time-base. The first sub-network may include one or more slave synchronization data source for generating slave clock synchronization data derived from time information of the master clocks. The second sub-network may include one or more slave clocks and a slave clock time-base controller connected to the slave synchronization data source. The time-base controller may receive the slave clock synchronization data and control one or more of the one or more slave clocks in accordance with the slave clock synchronization data.
摘要:
A data communication network may include two or more master clocks, and a synchronization system connected to the master clocks. The synchronization system may determine a time-base for the master clocks. The synchronization system may control the master clocks according to the determined time-base. The data communication network may include one or more slave clocks. The slave clocks may be controlled by a slave clock time-base controller based on time information of a single selected master clock selected from the master clocks.
摘要:
A method and a bit stream decoding unit for bit stream decoding has a bit stream comprising a number of consecutive samples. In order to provide for rapid and, in particular, reliable decoding of the bit stream, a detection window comprising a number of samples is defined and the detection window is positioned at certain positions on the bit stream in order to comprise certain samples with respective sample values. A majority voting is applied to the sample values in the detection window and, in dependence on the result of the majority voting, the bit stream is decoded and respective bit values are generated.
摘要:
A multi-node communications system is provided with communications protocol using both static (11, 12, 13, 18) (pre-determined) and dynamic (51, 52, 53 . . . ) (run-time determined) consecutive communication slots is used. The system has a number of distributed communication nodes, each node being arranged for communicating frames of data with the other nodes during both the static (11, 12, 13 . . . ) and the dynamic (51, 52, 53 . . . ) communication slots. Each node includes a synchronized time base 5 made up of consecutive timeslots (11, 12, 13 . . . , 51, 52, 53 . . . ). The timebase 5 has substantially the same error tolerance in each node. For static communication (10), a predetermined number of timeslots (20) are utilized for each static communication slot. For dynamic communication a dynamically allocated number of timeslots (60) are utilized for each dynamic communication slot. In this way both static and dynamic media arbitration is provided within a periodically recurring communication pattern. Communication jitter is well defined and dealt with, and large oscillator drifts are compensated for.
摘要:
A data communication network may, include a first sub-network and a second sub-network. The first sub-network may include two or more two master clocks, and a synchronisation system connected to the master clocks. The synchronisation system may, for determine a time-base for the master clocks and control the master clocks based on the determined time-base. The first sub-network may include one or more slave synchronisation data source for generating slave clock synchronisation data derived from time information of the master clocks. The second sub-network may include one or more slave clocks and a slave clock time-base controller connected to the slave synchronisation data source. The time-base controller may receive the slave clock synchronisation data and control one or more of the one or more slave clocks in accordance with the slave clock synchronisation data.
摘要:
A data communication network may include two or more master clocks, and a synchronisation system connected to the master clocks. The synchronisation system may determine a time-base for the master clocks. The synchronisation system may control the master clocks according to the determined time-base. The data communication network may include one or more slave clocks. The slave clocks may be controlled by a slave clock time-base controller based on time information of a single selected master clock selected from the master clocks.
摘要:
A multi-node communications system is provided with communications protocol using both static (11, 12, 13, 18) (pre-determined) and dynamic (51, 52, 53 . . . ) (run-time determined) consecutive communication slots is used. The system has a number of distributed communication nodes, each node being arranged for communicating frames of data with the other nodes during both the static (11, 12, 13 . . . ) and the dynamic (51, 52, 53 . . . ) communication slots. Each node includes a synchronized time base 5 made up of consecutive timeslots (11, 12, 13 . . . , 51, 52, 53 . . . ). The timebase 5 has substantially the same error tolerance in each node. For static communication (10), a predetermined number of timeslots (20) are utilized for each static communication slot. For dynamic communication a dynamically allocated number of timeslots (60) are utilized for each dynamic communication slot. In this way both static and dynamic media arbitration is provided within a periodically recurring communication pattern. Communication jitter is well defined and dealt with, and large oscillator drifts are compensated for.
摘要:
The invention refers to one of a number of nodes of a communication system. The nodes are connected to a communication media for transmitting data among the nodes. Said one node comprises a communication controller, across which the node is connected to the communication media, and a bus guardian for controlling access of the communication controller to the communication media. In order to provide a cheap but nevertheless reliable way for monitoring the synchronized clock signal of a node of a communication system and in particular for detecting deviations of the synchronized clock signal it is suggested that a synchronized clock signal from the communication controller is made available to the bus guardian, and that the bus guardian comprises means for monitoring the synchronized clock signal using a bus guardian internal clock signal, which is generated by means of an electronic circuit and which is less accurate than the synchronized clock signal to be monitored.
摘要:
A system for testing a logic circuit which has two or more test routine modules. Each module contains a set of instructions which is executable by (a part of) the logic circuit. The set forms a test routine for performing a self-test by the part of the logic circuit. The self-test includes the part of the logic circuit testing itself for faulty behavior, and the part of the logic circuit determining a self-test result of the testing. The system includes a test module which can execute a test application which subjects the logic circuit to a test by performing the self-test on at least a part of the logic circuit by causes the part of the logic circuit to execute a selected test routine, and determining, by the test module, an overall test result at least based on a performed self-tests. The test module includes a control output interface for activates the execution of the a selected test routine. A second test module input interface can receive the self-test result from a selected test routine. At a test module output interface the overall test result may be outputted. The test routine includes instructions for outputting, by the part of the logic circuit, data to a test routine output interface which is not connected to the second test module input interface, for outputting information about the self-test result by the test routines without passing the information through the test module.