Method for transmitting process data between master driver and slave driver based on CAN bus

Abstract

The invention discloses a method for transmitting process data between a master driver and a slave driver based on a CAN bus. A master station servo driver periodically broadcasts a frame through the CAN bus to add a data frame of a 1-byte counter, the initial value of the counter is 0, and 1 is added to the value of the counter after the data frame broadcasted by the master station servo driver is successfully sent; each slave station servo driver receives the data frame broadcasted by the master station servo driver, analyzes the data frame, performs remainder operation processing on the obtained value of the counter, and further determines whether to feed back updated state information to the master station servo driver according to the remainder. The method has the advantages that the situation that a plurality of slave station servo drivers feed back state information at the same time does not exist, the phenomenon of data collision does not occur, frame synchronization of a CAN link layer is not affected, arbitration failure of a certain slave station servo driver with a low priority is not caused all the time. Therefore, the master station servo driver loses the state information of the slave station servo driver with the low priority for a long time.

Description

technical field [0001] The invention relates to a process data transmission technology between master and slave drives, in particular to a CAN bus-based process data transmission method between master and slave drives. Background technique [0002] In industries such as injection molding machine manufacturing and forging press manufacturing, high-tonnage machines are not realized by a set of servo drives, motors and oil pump power units, but by combining multiple sets of servo drives, motors and oil pump power units. This solves the problems of high procurement cost of high-power components, long delivery cycle of non-mainstream components, and complicated after-sales maintenance. The most common method of coordination between multiple sets of servo drives is: the master station servo drive periodically broadcasts data frames to each slave station servo drive through the CAN bus, and each slave station servo drive feeds back its own status information to the master station s...

AI Technical Summary

Problems solved by technology

Although it is simple to implement this general method of process data transmission between master and slave servo drives, it does not take into account that multiple servo drives send frames at the same time (that is, the data frames broadcast by the master servo drive, from status information fed back by the station servo driver), so not only data collisions will occur, but also the frame synchronization of the CAN link layer will be affected; at the same time, when the number of slave station servo drivers is large and the command cycle is short, even It will cause a low-priority slave servo driver to always fail to arbitrate, and the master servo driver will lose the status information of this low-priority slave servo driver for a long time, which may also affect the slave servo driver receiving the master servo. Data frame broadcast by the driver

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