CANopen协议的详细说明，清楚的解释了什么是对象字典，以及SDO，PDO的通信规范，对CANOPEN通信状态机也作了说明。-CANopen protocol details, a clear explanation of what is an object dictionary, and SDO, PDO' s communications standards, for CANOPEN communication state machine are also described.

spi eeprom 通讯，通讯这块可以只用PDO方式传输而不用SDO方式传输，对象字典的参数部分存在PDO，部分存在SDO，当第一台伺服驱动器去修改第二台伺服驱动器对象字典中的参数时只能用SDO传输方式。-spi eeprom community

PIC18F单片机根据CIA301标准编写的CANOPEN通讯，可以实现NMT、SDO、PDO功能。(PIC18F microcontroller in accordance with the CIA301 standard written in CANOPEN communication, you can achieve NMT, SDO, PDO functions.)