Conveyor system controller, conveyor system and method of data synchronization

A method of data synchronization between a plurality of conveyor system controllers of a conveyor system,

• wherein each conveyor system controller comprises:
• a data storage unit configured to store a plurality of data entries, each data entry comprising a data entry ID, a data entry version identifier, and a data payload representing operating information of the controller or another controller;
• a processing unit;
• and
• a first interface for communicating with said another controller;
• the method comprising, in each controller:
• transmitting a first heartbeat data packet comprising data entry ID and data entry version identifier of a data entry in the data storage unit, via the first interface, to other controllers;
• receiving a second heartbeat data packet transmitted by said another controller, via the first interface, the second data packet comprising data entry ID and data entry version identifier of a data entry of said another controller;
• and
• comparing the received data entry version identifier of the second heartbeat data packet, with a data entry version identifier of a corresponding data entry in the data storage unit having a same data entry ID as the second heartbeat data packet;
• wherein, when the controller determines that the data entry stored in its storage unit is newer than the corresponding data entry in said another controller, the method comprises:
• transmitting to said another controller a first synchronizing data packet comprising the data entry ID, the data entry version identifier, and at least a portion of the data payload, of the corresponding data entry in the data storage unit;
• wherein a size of the first synchronizing data packet is greater than a size of the first heartbeat data packet;
• receiving a second synchronizing data packet comprising a second data entry ID, a second data entry version identifier, and at least a portion of a second data payload, of a second data entry in said another controller's data storage unit,
• wherein a size of the second synchronizing data packet is greater than a size of the second data packet, and
• when the second data entry version identifier of the second synchronizing data packet is indicated as newer than a data entry version identifier of a corresponding data entry in the data storage unit, the method further comprises updating the data payload and the data entry version identifier of the corresponding data entry in the data storage unit, according to the portion of the second data payload and the second data entry version identifier of the second synchronizing data packet;
• wherein each controller further comprises a second interface for communicating with an external unit;
• wherein the method comprises, in each controller:
• receiving a first signal from the external unit, via the second interface, for updating a data payload of a data entry in the data storage unit;
• updating the data payload of the data entry in the data storage unit according to the first signal;
• and
• updating the data entry version identifier of the updated data entry to indicate a newer version.