The ESC requires non-volatile memory (for example,
an EEPROM with I2C interface), which is referred to as the SubordinateDevice Information
Interface (SII) memory, to store the EtherCAT SubordinateDevice Information
(ESI) data.
The ESI data contains information about the SubordinateDevice device
identification, supported features, and other network accessible properties.
Note: The ESI XML file is generated from Beckhoff's
SubordinateDevice Stack Code
(SSC) tool.
- EtherCAT SubordinateDevice
- Uses the SII upon
power-on or reset to load configuration data into the EtherCAT SubordinateDevice
configuration registers.
- EtherCAT MainDevice
- During development, the
MainDevice is used
to program the device SII memory with the ESI data.
- When the ESI file isn't
provided to the MainDevice, the MainDevice reads
the device SII memory upon boot-up to determine the SubordinateDevice
device properties such as the process data and their mapping options,
the supported mailbox protocols including optional features, as well as
the supported modes of synchronization.