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EtherCAT:DIGITAL-IOS Digital Inputs/Outputs.

The front page is EtherCAT

The user can associate between system digital Inputs/Outputs and a motion drive’s digital inputs/outputs or an IO module inputs/outputs.
This association allows the user to set/get those IOs using the following MC-Basic syntax:

Read inputs:
?Sys.din[<first system digital input bit>][<Range>]

Write outputs:
Sys.dout[<first system digital output bit>][<Range>] = <value>


It is up to the user to assign system IOs carefully, and make sure that the same system IO isn't mapped
to more than one IO (of a motion drive or an IO module).

Behavior is UNDEFINED if this rule is broken !!!

Attaching System IOs to EtherCAT slave IOs

In an EtherCAT slave the digital IOs are handled by reading/writing to certain objects. These objects are mapped to PDO. Naturally, inputs are mapped to Tx PDOs (Slave to Master) and outputs are mapped to Rx PDOs (Master to Slave). The association between the relevant PDO, number of IOs, etc, is done using the subroutine EC_ASSOCIATE_PDO_TO_SYS_DIO.

Please refer to the page EC_INSTALL_STX_CDHD for an example how to use this function.