基于S12X系列双核单片机的CAN网关设计

集成XGATE协处理器内核的S12XE系列双核单片机具有处理速度快、反应时间短、功耗低等优点,在嵌入式应用中具有独特优势和很好的应用前景。本文采用16位双核单片机MC9S12XEQ512作为主控制器,以集成信号和电源隔离功能的CAN收发器芯片ADM3053来实现CAN接口电路,设计并实现了一个可以连接3个CAN通信子网的CAN网关,有效实现了系统的小型化、低功耗、低成本。采用双核处理技术来优化CAN网关的处理流程,由协处理器XGATE来处理各种中断,S12X主CPU则专注于协议处理和消息转发。实际应用表明,系统运行稳定可靠,与传统的采用单处理器实现的CAN网关相比,系统的数据吞吐能力和实时性得到了明显改善。

Design of CAN Bus Gateway Based on S12X Series Dual-core MCU

S12X series dual-core MCU with a coprocessor XGATE has the advantages such as high speed of data processing, short reaction time and low power consumption. So it has more good application prospect in the field of embedded application. In this design, the 16-bit dual-core MCU named MC9S12XEQ512 has been selected as the main processor. The CAN transceiver chip ADM3053 has been used to implement the CAN interface circuit, in which CAN transceiver, the signal isolation function and isolated DC-to-DC converter are all integrated. The paper describes the design and implement of CAN gateway having three CAN interfaces for solving the CAN network"s extending and interconnection, achieving the purposes of interface miniaturization, low power consumption and low cost. The technology of dual processors in embedded system design has been also applied to optimize the performance of the gateway. The coprocessor XGATE is used to handle the miscellaneous interrupts and the main processor S12X CPU is used to analyze the protocol and exchange messages. The application results show that the gateway can work stably and reliably. Compared with the existing gateway realized by the traditional single core processor, the performance of data throughput and reliability has been improved.