59results about How to "Realize time synchronization" patented technology

The invention discloses a multi-core system time synchronization method and a system thereof; the time synchronization method comprises the following steps: A, establishing at least a clock synchronization domain, and distributing the cores respectively into each lock synchronization domain; B, selecting the core with the minimum load as the master clock synchronization source in each clock synchronous domain, and taking the clock synchronization domain having the master clock synchronization source with the minimum load among all the master clock synchronization sources as the master clock synchronization domain, and taking the other clock synchronization domains as the slave clock synchronization domains; C, after the master clock synchronization domain sends synchronization error detection information to each slave clock synchronization domain, calculating the time deviation value between each slave clock synchronization domain and the master clock synchronization domain; D, when the time deviation value is greater than the permitted deviation value, the master clock synchronization domain calculates the time adjustment quantity of each slave clock synchronization domain and releases the time adjustment quantity to each slave clock synchronization domain, then each slave clock synchronization domain makes adjustment based on the corresponding time adjustment quantity. The invention effectively solves the time synchronization problem of the multi-core system.

The embodiment of the invention discloses a method and device for selecting anchor masters. Time synchronization of equipment in an NAN cluster can be kept. The method comprises the steps that the equipment receives NAN Beacon frames carrying first AM information and first TSF information, and the first AM information comprises the first AMR, the first HC and the first AMBTT; if the NAN Beacon frames are used for selecting AMs, when the first AMR is smaller than the second AMR and the MR of the device is greater than the first AMR, the role of the equipment is converted into the AMs, second AM information of an equipment record comprises the second AMR, the second HC and the second AMBTT; if the NAN Beacon frames are used for selecting the AMs, when the first AMR is smaller than the second AMR and the MR of the equipment is smaller than the first AMR, the equipment updates the second AM information and second TSF information of the equipment record according to the NAN Beacon frames.

In a ring type network, a master node transmits a determination packet to a slave node; receives the determination packet having taken a round of a plurality of slave nodes; stores determination packet transmission and reception times in accordance with the timings of an internal clock; and transmits a transmission result notifying packet, which is indicative of the determination packet transmission and reception times, to the slave node. Each of the slave nodes receives the determination packet; transmits the received determination packet to a next node; stores a determination packet reception time in accordance with the timing of an internal clock; also receives the transmission result notifying packet; calculates a time correction value by using the determination packet transmission and reception times indicated by the received transmission result notifying packet, the stored determination packet reception time, the total number of the node apparatuses and using a difference in packet transfer order between that slave node and the master node; and corrects the time of the internal clock by using the calculated time correction value.