Running Virtual EtherCAT device on virtual Linux

[phamnhatha090805]

Hello,

I have came across this library and I'm trying to run a virtual EtherCAT device on my Linux virtual machine. What I did is I operated the freedom-k64f or xmc4800 in the lo (loop back port). However, when I scanned the network with scanTopology tool, I could not detect any slave. Has anyone had this problem before? Any helps, supports, or documentation appreciated!

[leducp]

'lo' is not a suitable interface for this usecase: as soon as a frame is sent in this interface, the simulator will loop on it indefinitely because both sides (simulator and client, here scanTopology) are both connected to TX and RX together.

However, while reading the code and the README I encounters a few bugs in theses tools: PR #346 shall fixed theses.

If possible, the best way to connect the network simulator is to use the tap socket:
tap:server for the network simulator
tap:client for the standard master (here scanTopology)

Otherwise you can create a linux tap interface or start the simulator on another system to use a real network interface (or use two interface on the same machine to create a real loopback).

[phamnhatha090805]

Thank you so much! Now, I can do the simulation on a Raspberry Pi.

I have a question about another thing. I tried to simulate my actual EtherCAT slave, so I import the XML file, and the EEPROM BIN file of my own EtherCAT device. Then, I create a JSON file point to those files. But when I run the network simulator or the od_generator, it give me "Segmentation fault". I don't think the problems come from my XML file or BIN file because my EtherCAT device with these files are still working well with the TwinCAT. Can you please try to take a look into this problem? I also attached the XML file, the BIN file and the JSON file of my EtherCAT device.
sample_app_C.xml
LAN9253_SAMD51.json
Box 2 (sample_app_C).zip

[leducp]

I'll do a pass on your files this weekend. I didn't have the chance to put my hand on many ESI files so far so my guess is that the EsiParser class is buggy somehow. Thanks for the sharing it will be useful!

[phamnhatha090805]

Yes, we did find some bugs in the EsiParser. We modified the EsiParser a bit and now we can emulate our own EtherCAT device on the Raspberry Pi using network simulator.

[trns1997]

@phamnhatha090805 we just merged probable fixes to the bugs you mentioned here #347. It would be great to get you input on @leducp fixes. Hopefully it resolves everything

[phamnhatha090805]

Thank you for the fixing!
I'm trying to scan the virtual EtherCAT device that run on the Raspberry Pi using TwinCAT. However, the device cannot change to OP state and the TwinCAT is sending messages complaining about the SM watch dog. I have changed the EmulatedESC::checkWatchdog() function to be more robust and now the virtual device can go to the OP state. I will try debug a bit more and analyze the behaviour. If everything go well and you agree, I will do a pull request for you to review the changing.

[leducp]

With pleasure: the emulated ESC is in a "work in progress" state, expecially because I cannot test it with other master implementation. Any PR that improve its behavior are welcomed :)