More advanced EtherCAT setup questions

If you really wanted to lock it down you could try using the comp component with your lcec.0.slaves-responding against the expected number of slaves (eg set with setp). Then if you used estop-latch to manage your estop (which you should be using anyway), you could add an additional estop-latch in your estop chain so the machine could not be enabled until all slaves report in.

@spumco I think the underlying functionality (i won't say issue, as it's probably intended functionality) of drv-fault is in the lcec component, as once the drives unplugged, the drive can't really report a problem, and they don't trigger an error if communication is lost, they simply go idle.
I'm assuming the drv-fault only triggers once the drive actually errors, but I've not found an easy way to get the drives to fault yet, although i did just think about how to do it without risking blowing one up.

@rodw that's the kind of thing that I'm aiming for.

I haven't read deeply in to lcec component, but I wonder if there's a polling process to check for changes.  I'd be interested if drives change state on some parameter if they're disconnected.

spumco wrote:

I haven't read deeply in to lcec component, but I wonder if there's a polling process to check for changes.  I'd be interested if drives change state on some parameter if they're disconnected.

Looking at the ethercat documentation, the main parameter I can see is lcec.<m>.slaves-responding, which does what it says.
It doesn't appear to refresh that quickly, although that may just be that Halshow is slow to update.
I'd guess should a slave disappear during motion, a joint following error is likely to be triggered quicker.

Going back to setting drive parameters, is there anyway to set ModParam with the generic cia402 driver, by addressing the required register directly and not using a 'named' parameter?

Just took a look at your drive manual, and it's... really sparse.

I don't know of anything in lcec or cia402 that constantly polls the drive(s) for communication status, but I had an idea that might be worth exploring...

What I was thinking is to use one of the drive's digital outputs as a tattle-tale.  It's not clear in the manual if the DOs reset on loss of communication, but on my Stepperonline A6's that's an option only found in the tuning software.

I can program my drives' digital outputs to either retain the last state or turn off if communication is lost.

If you can set yours to turn off, then you could create DO hal pins in xml file.  Those pins are then turned on in HAL whenever LCNC is running.  The DO is then connected to an LCNC input - a DI on a different drive or other Ethercat slave device.  That input is connected to motion.external-fault-NN - and it all acts like a drive communication estop.

If the drive is unplugged, the DO turns off... then input then turns off, which triggers an external fault in LCNC.

It all depends if you can set the outputs to non-latching in the drive tuning software and you have a spare input somewhere.

Reminds me I need to test my own system for an Ethercat cable failure.