Time correction processing method and device and computer storage medium

Abstract

The invention discloses a time correction processing method and device and a computer storage medium, and the method comprises the steps: determining the duration from the current random millisecond moment to the next whole second or the later second whole second as the interval duration when the verification processing is started; and controlling the master station to sleep at an interval beforethe master station sends the time correction message subjected to the time correction processing. According to the embodiment of the invention, the time correction error of time correction processingis reduced, and the operation quality of an automatic system is improved.

Description

technical field [0001] This article involves but is not limited to automation technology, especially a method, device and computer storage medium for time correction processing. Background technique [0002] The Modbus protocol is a balanced response communication protocol widely used in the field of industrial automation, and has become a general industrial standard. The Modbus protocol supports traditional serial (RS-232, RS-422, RS-485) and Ethernet devices. Modbus communication uses master (Master, also called master station)-slave (Slave, also called slave station) technology, that is, at the same time, only one master device can initiate the query (also called request, sequential query is called polling), slave The device responds accordingly according to the content of the message provided by the master device. The master device can communicate with the slave device alone, and can also communicate with all slave devices in broadcast mode; when communicating alone, t...

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Problems solved by technology

2. The master station takes the current time of the master station at a random number of milliseconds, rounds the number of milliseconds (five rounds means adding one to the number of seconds), and packs the time information including seconds and above according to the protocol format agreed by both parties The completion time message is sent to the slave device, and after the slave device obtains the time information provided by the master station, it corrects the local clock of the slave device; because the milliseconds at the moment when the time calibration process is initiated is random, but after simple rounding, the time calibration error is -500~499 milliseconds

3. The master station specially designs an accurate timing timer, which is expected to be triggered on time when the system time is 0 milliseconds, so as to complete a time calibration of the slave device; this method expects the timer to be triggered on time at 0 milliseconds, Not every operating system and every hardware platform can be implemented, and in a multi-threaded environment, it is impossible to ensure that the central processing unit (CPU) can trigger the timing timer on time at 0 milliseconds; in addition, even if it is triggered on time Timing timer, because Modbus is a response protocol, all requests from the master station to the slave devices must be queued in turn. At this time, if a question and answer from the master station is not completed, the timing operation must be queued.

[0006] In summary, the timing accuracy of existing timing methods in related technologies needs to be further improved

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