Why do I receive TCP/IP communication errors when I try to operate my Simulink Real-Time target computer as the EtherCAT main device?

I am using a Simulink Real-Time (SLRT) target computer that communicates with multiple subordinate devices via EtherCAT. I am able to successfully build the model and load it onto the target. However, when I start the real-time simulation, I receive errors in MATLAB such as:

Error 1:

ERROR: External Mode Open Protocol Start command failed

Error 2:

ERROR: Executing the 'Start' command produced the following error:
TargetPC1: TCP/IP timeout while receiving data

Error 3:

ERROR: Executing the 'FinalUpload' command produced the following error:
TargetPC1: TCP/IP Read Error

At the same time, the target screen displays the following output:

System: initializing application finished
System: model thread stack is 64K bytes
EtherCAT Update rate 0.00025 sec
Could not set master state to PREOP
ERROR: EtherCAT error: No Error

System: execution cannot be started
System: execution stopped at 0.000000
Rx time is 0.000001
Cycl time is 0.000000
McSt time is 0.000003
MasterTimer is 0.000004
AsynctTime is 0.00000
xpcEtherCATstop called
EtherCAT Update rate 0.00025 sec

Answer 1

[MathWorks Support Team]

The above error messages may indicate that there is a conflict between the Ethernet ports used for the host-target connection, and the one used to connect to the EtherCAT network. This may be due to incorrect settings in the EtherCAT Init block.

R2020a and earlier:

Ensure that all fields (such as "PCI Bus" and "PCI Slot") within the EtherCAT Init block are specified correctly, i.e., they match with the actual hardware setup.

R2020b and later:

Use the Ethernet Configuration utility (speedgoat.configureEthernet) which is part of Speedgoat I/O Blockset to reserve the correct Ethernet port for the EtherCAT Master:

https://www.speedgoat.com/help/slrt/page/io_main/refentry_ethernet_configuration

If everything is specified correctly and the issue persists, please check that the network card(s) work.