Abstract : This paper addresses the shortcomings of low communication speed and high data transmission error rate in microcomputer protection and control systems by designing a microcomputer protection and control device based on the CAN fieldbus. In this paper, the authors construct a microcomputer protection and control system with the TMS320F2812 embedded eCAN module as its core, taking advantage of the features of the enhanced CAN controller module, and present the hardware design scheme. In terms of software design, the collected information is communicated with the monitoring computer via the CAN bus, thereby realizing remote control and real-time monitoring. Furthermore, considering the specific application of the microcomputer protection and control device, the authors define the application layer communication protocol and detail the design method and process of the communication software. Communication experiments were conducted to verify the system's reliability and accuracy. To facilitate user understanding of the monitoring and control status, an LCD and keyboard module was designed, enabling real-time data display and action information query functions. This device has been applied in the field with reliable and effective operation, and has certain reference value. Keywords : TMS320F2812, eCAN, microprocessor-based line protection 1. Introduction The communication technology between microprocessor-based protection and control devices is an important indicator of the sophistication of a substation automation system. The initial communication technology used RS485 bus, employing a master-slave communication method. While simple, this method revealed many problems in actual operation: low communication speed, generally not exceeding 9.6Kbps, and a high error rate when transmitting large amounts of data; it also prevented the inclusion of more than one master in the communication network, thus failing to utilize the superior performance of multi-master technology. As users continuously raised new requirements for the functionality of substation automation systems, attention turned to the CAN fieldbus. Currently, TI's TMS320F2812 DSP chip embeds an enhanced CAN bus controller eCAN module, offering more flexible and convenient data transmission, larger data volume, higher reliability, and more complete functionality during CAN bus communication. This system uses the TMS320F2812 embedded eCAN module to enable communication between each functional unit and the main control computer, thereby achieving remote transmission and exchange of information, making the system more stable and reliable, and providing more flexible communication methods. (Full text download available for "DSP Embedded eCAN Module in Microcomputer Protection and Control System")