CAN总线技术在光电编码器中的应用

Application of CAN bus technique to photoelectric encoders

介绍了光电编码器CAN总线接口的设计与应用。设计了由单片机、独立CAN总线控制器SJA1000、CAN总线收发器TJA1050及高速光耦TLP113等构成的光电编码器CAN总线接口硬件电路;给出了光电编码器CAN总线接口的软件设计,包括初始化设计、CAN总线报文接收及发送设计;最后,通过周立功公司的"USBCAN1"型号CAN总线接口卡验证了该光电编码器CAN总线接口设计的可行性。实验中采用1m长的屏蔽双绞线作为传输介质,通信速率达800kb/s,误码率<10-11。实验结果表明:带有CAN接口的光电编码器克服了传统的通信线路的缺点,具有更高的实时性、可靠性,且通信速率高、传输距离长、抗干扰能力强。

A photoelectric encoder CAN bus interface is designed for use in a transmission system based a CAN bus. The hardware circuit of the photoelectric encoder CAN bus interface is presented, which is composed of a singlechip, a CAN bus controller SJA1000, a CAN bus transceiver TJA1050 and a high-speed optical coupling TLP113. Then, the CAN bus interface software is designed, including the design of initialization and the design of receiving messages and sending messages. Finally, the feasibility of photoelectric encoder CAN bus interface is proved by a “USBCAN1” CAN interface card produced by ZLG Company. Experimental results indicate that communication rate has been up to 800 kb/s and the error code rate is less than 10TM when the one-meter shield twisted pair line is used as the transmission medium, which shows that the photoe- lectric encoder with CAN bus interface overcomes shortcomings of communication lines in classical photoelectric encoder systems, and has the advantages of more real-time and reliability, high transfer rates, long transfer distances and high resistances.