Ethercat SDOS to XML

So in summary, this slave won't let you set SDO's again after they are set. Power cycling the slave resets all the SDO's to zero and allows linuxcnc to set them as per the ethercat xml file

Any clues in syslog?

Hakan wrote:

Any clues in syslog?

noe that I saw. I think the slave may misbehave. in some places it says you can't change values once they are set

Have you tested the module in Twincat yet?
If it runs without any issues there, you could use Wireshark to monitor the communication. Maybe that will turn something up.

After you set it the first time, does it disappear from the sdos listing or does it just become read-only?

andrax wrote:

Have you tested the module in Twincat yet?
If it runs without any issues there, you could use Wireshark to monitor the communication. Maybe that will turn something up.

I do not use Windows here! 
Well I sometimes did until this last week dual booting to run Anycubic Slicer Next for my 3D printer but now I have it working under Linux so I am never booting into Windows again just to be beseiged with ads. 

I understand.

I would have chosen that approach.
First, set up a system where the module runs, and then read the communication data.
I think it’s very consistent of you not to use Windows.
Respect.
As far as I know, there are also system managers that run on Linux.
Would that be an option?

I've actually got bigger problems here now.  I am not getting proper communication between linuxcnc's lcec driver and the ethercat slave.

I don't have any errors on startup but if I toggle an output from halshow, the light comes on in halshow but the actual state does not change on the device. This worked previously but on a different config. eg, this no longer toggles the physical outputs.


I can set the same output pins on and off using the ethercat upload and download commands.
I Stripped out all of the SDO commands for modbus but it is still not working. Not sure how to resolve this issue.

Ahh, now I have it working again. dmesg showed an error loading my xml but Linuxcnc was silent on this. I missed something! Now I will add stuff back in slowly.

I don't really have anything here like a USB to 485 adapter to test vfd comms with and there are no status lights.

What I have worked out uploading registers is that I have a timeout error and the error count increments all the time

I think I have worked out all the XML syntax and settings.

SO when uploading an SDO in dmesg, I get 
SDO download aborted
Unsupported access to an object 

I mighht try configuring with ethercat download commands before starting. Wierd

Success! I used Ethercat download to set the parameters for one VFD register to measure the bus voltage instead of the ethercat-conf.xml file and I got a reading that changed from time to time. At one stage it was at 321.0 which also showed up on the vfd console. This is meant to be intermediate DC power which should be  1.414 x mains power input. Working backwards, that was 227 volts (should   be 240 volts). So learnings are:
1. Once a SDO is set, it can't be changed
2. You need to set the SDO's via Ethercat download, not via XML
3. SDO's are cleared when the slave is powered off. 

Out of time now but It looks like I'll be able to get this going now. It was frustrating not being able to see anything at all.

Thanks for the help....