关键词: CKS32, CAN总线, IAP, 断点重传, 多节点

Abstract: A remote online upgrade solution based on CAN bus and IAP technology was proposed, which could solve the inconvenience of firmware updates in distributed control systems. The solution successfully achieved synchronous online upgrades for single and multiple nodes. In this solution, the PC host computer was designed using PyQt5 Python, and communication interaction with the various CKS32 CAN slave nodes was realized through a USB-to-CAN interface. The CKS32 CAN slave nodes were based on the IAP technology feature, which divided the on-chip Flash into four segments and loaded code in a time-division manner. To avoid abnormal interruptions and errors during data transmission, the system has been equipped with a mechanism for resuming transmission from the point of interruption, counting, and CRC16-MODBUS verification, thus improving the security and efficiency of the upgrade. After testing, the total upgrade time in the distributed system was shortened, the upgrade success rate was greater than 95%, and even if the CAN slave node upgrade failed, it could report the results and continue to operate according to the previous state.

Key words: CKS32, CAN bus, IAP, breakpoint retransmission, multiple nodes