TECO JSDG2S-20A-EL - Page 555

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(3) Communication structure
EtherCAT communication can be applied to various application protocols. The application layer
protocol which JSDG2S-E servo driver utilizes is IEC 61800-7─CANopen motion control subprotocol.
In the servo driver, the system structure related to EtherCAT communication can be divided into
three parts: physical layer, data-link layer and application layer. The servo driver receives information
sent from the controller by physical layer, judge and process the received information by data-link layer
and lastly, distribute corresponding information to belonged CiA402 object by application layer to control
the servo motor.
(4) State machine
In the servo motor, there are two types of transmission available: Mailbox and Process data. In
EtherCAT communication protocol, these two types are controlled by state machine to facilitate the user
to choose the desired control method. Communication state machine can be divided into four states: Init,
Pre-Operationa-l, Safe-Operational & Operational. Under the selected corresponding mode, the user can
choose if to enable/disable Mailbox and Process data transmission respectively.
JSDG2S-E Servo Drive
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Data-link la
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e
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EtherCAT Ph
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sical La
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e
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Cia402 Ob
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ect dictionar
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Control Mode
switch
Servo Driver A
pp
lication
Register
Application Layer