关键词: STM32H743, I²C通信, 多主机系统, 电路老炼, 批量监控

Abstract: Aiming at the problems of hardware redundancy, high system complexity and high cost caused by the "single-master-single-slave" communication mode in traditional circuit burn-in test, this paper designs and implements a multi-channel I²C batch communication system based on STM32H743 microcontroller. In terms of hardware expansion mechanism, the system configures 25 groups of General Purpose input/output (GPIO) pins of STM32H743 and adopts software simulated I²C (Bit-Banging) timing, breaking through the bottleneck of the limited number of hardware I²C peripherals of the microcontroller, and successfully expands 25 groups of completely independent I²C master interfaces. In terms of centralized monitoring mechanism, the system adopts a master-slave polling structure combined with the core scheduling strategy of dual-loop traversal algorithm: the outer loop switches the communication target according to the address group, and the inner loop traverses all physical slaves within the group. Through time-division multiplexing mechanism, the state data collection and anomaly detection of up to 25×X (X is the number of slaves supported by a single master) slave circuits are realized, forming a systematic centralized supervision. The test results show that the system can read back and display all slave states in real time, the anomaly detection response time is less than 100 ms, and the success rate of cumulative more than 4.4 million communication transactions exceeds 99.95% after 48 hours of continuous testing at 125°C high temperature. Compared with the existing similar schemes relying on dedicated switching chips or multiplexers, the core engineering principle innovation of this scheme lies in the use of pure software simulation to achieve large-scale I²C host expansion, abandoning additional hardware dependence, thus bringing significant advantages in engineering application: a single motherboard can centrally manage hundreds of nodes, and the system complexity and hardware cost are estimated to be reduced by more than 40% compared with the traditional scheme, providing a higher cost-effective, simpler and more reliable new solution for mass screening of high-reliability electronic equipment.

Key words: STM32H743, I²C communication, Multi-master system, Circuit burn-in test, Batch monitoring