Does NI master support FoE ethercat communications?

[sillyfish]

Hi,

Having troubles getting a straight answer on this, so I thought I'd post. I need to hook up a third party slave to a NI cRIO EtherCAT master. I need to transfer a large amount of data (~several MB) to the slave device. Do the NI cRIO master devices support "File over EtherCAT" (FoE) communications? The slave device was designed for use with Beckhoff TwinCAT, and used FoE for data transfer from TwinCAT (I can't use TwinCAT for what I'm doing, however).

I found this page that says Labview/cRIO uses FoE to flash firmware for the NI-9144 module. However, I'm not looking to overwrite the firmware on the slave, only send the slave some data via FoE. Is what I'm seeking to do possible?

Apologies in advance if it sounds like I don't know what I'm talking about... because I don't. This EtherCAT thing is rather new to me.

[a_clucker]

Hi sillyfish,

This is a good question. I'm talking with one of my colleagues to get a more definite answer, and one of us will reply when we have more information. 

Right now, it sounds like you have a good grasp of the information that's out there.

"Do the NI cRIO master devices support "File over EtherCAT" (FoE) communications?" Yes**

**but, not as a blanket statement. It does support FoE to transfer firmware and custom bitfiles to the NI slave (9144). My colleague and I are looking into what else, if anything, should be added to this " ** " explanation.

Perhaps someone on the forum will chime in if they have tried, successfully or not, to transfer files via FoE to a 3rd party slave using an NI Master.

[TheEngineeringBear]

What kind of Data are you trying to send the the Ether Kitten?

In my experience I have never passed a file to an Ether kitten and/or received one from it outside of updating the bit file.  Can you tell us what your use case and application is to have a more accurate understanding of what you are trying to do?

-Bear

[karupinwendy]

Hi,

NI EtherCAT master supports FoE communication as long as the 3rd party slave you are using is compatible with our master and the slave also supports FoE itself.

You can refer to the Write FoE example VI shipped with NI EtherCAT driver. The example is located here:

But you need to re-structure the VI based on your slave's spec about FoE data transfer.

One thing to note is that FoE transfer in EtherCAT needs to be in Bootstrap mode. All the FoE related information in the ETG (EtherCAT Technology Group) spec tells that. So you cannot use the FoE Write example VI in active mode.

You can tell me what kind of data you want to send to slave and why you need to do it using FoE. I may be able to give you more advice.

Wendy

[sillyfish]

Thank you everyone, I'll give it a shot and come back if I have more questions.

Sillyfish

[sillyfish]

Hi everyone,

I'm back... 

Bear, the slave (=kitten?) I'm using controls a large series of devices (let's say motors). They have some rather complicated settings that need to be set by a parameter file. There's also a status file that I need to pull off the slave using FoE. I'm guessing the creator did this because it would take an insane number of SDOs to accomplish the same thing. 

Wendy, I studied the "Write FoE.vi" example, and I think that's exactly what I'm looking for. The only problem is the "IndComECAT" class in the example seems to only support writing via FoE. Is this the case? I'm surprised that there is the ability to write, but not the ability to read.

Is there anyway to read something off the slave through FoE? At very least, I would like to readback to verify the data sent to the slave.

Sillyfish

[TheEngineeringBear]

I don't think you are going to be able to do what you are hoping to.  The Ethercat protocol NI uses treats the Ether Kittens (yes ethercat slaves) as extensions of the master chassis.  All it is used for is communicating data across the network in a deterministic fashion.  This is not meant for file transfer and collecting data on the ether kitten's.

Understanding it this way I do not believe there is a way of doing file transfer to the ether kittens like you are looking for.  It wouldn't be supported as well.

-Bear

[karupinwendy]

Hi,

Sorry for late response.

I am afraid current NI master does not support FoE read from slave. But we have plan to support it in the furture.

Wendy

[MichaelAivaliotis]

Can someone from NI update us on when this future will be? I need this feature.

[MichaelAivaliotis]

If anyone wants to convince NI to add this feature, please vote for it here:

https://forums.ni.com/t5/Additional-NI-Software-Idea/Add-support-for-ReadFoEData-for-Ethercat-Read-d...

Thanks.