EtherCAT Master System Development Based On Embedded Linux

The serious slowness of the traditional fieldbus’s transmission rate has become the bottleneck of development of the servo-controlled system which seriously hinders the servo-controlled system’s development. With the advent of the EtherCAT, this problem is completely solved. Depending on its ultrahigh communication rate and many other advantages, it rapidly takes the leading role in the field of motion control. But the design of EtherCAT master is mainly based on PC at present and its huge mass and size makes itself inapplicable in many occasions. Hence, the EtherCAT master based on ARM is designed in this thesis.First, the technique and principle of EtherCAT are analyzed in detail in this thesis. Then the hardware platform of EtherCAT master based on the ARM9 and Ethernet control chip DM9000 is designed. And the software code is overall and hierarchically designed which is divided into 3 layers and 5 modules.The drive of EtherCAT at the lowest level is used to receive and dispatch the hardware data frame and realize the support for EtherCAT protocol. The protocol of EtherCAT master runs in the kernel layer. It realizes the work of the data link layer of EtherCAT, including mailbox communication process data communication and other basic communication operations, and the support for CANopen application layer protocol by CoE interface. The application program at the top level is designed based on the application layer of CoE and realizes two operating modes:velocity control and position control. The experiments of the communication and motor motion control are successfully carried out on the platform of EtherCAT master based on embedded Linux which is designed in this thesis. The functions of communication and application of EtherCAT master are verified in the end. Experimental results show that the communication function of communication function has been fully implemented. Additionally, embedded EtherCAT master can control motor simply, and the control cycle is 5ms.The main innovation of this thesis is the design of EtherCAT master based on the ARM platform which is barely studied both at home and abroad. In view of the huge advantages of ARM and with the constant improvement of the hardware performance of ARM, the servo-controlled system based on the embedded platform will be definitely widely used. Basing on this background, the EtherCAT master based on the embedded platform is designed in this thesis. It takes the first step in this field and provides the platform for future development.