Huanyang VFD Not Receiving

I'm not sure what changed, but a couple days ago I suddenly noticed LCNC isn't receiving data from the VFD. I haven't changed anything in HAL but wanted to see if anyone had ever heard of such a thing. I've rewired it twice thinking maybe it was due to an electrical issue, but nothing has worked. LCNC is controlling the VFD just fine and I'm not getting errors, just no signal from the VFD.

Possibly the USB-serial device has changed ID. Have you plugged in another USB-serial device?

Unplug the USB-serial device (assuming you are using one) and
ls /dev/
Then plug it back in, repeat the
ls /dev/
and check that the device that appears matches the device in the loadusr hy_vfd line in your HAL file.

Thanks for the help. I tried that and it didn't end up being the issue. While watching the Machine > Show Hal Configuration I noticed the pins for the hy_vfd aren't loaded until you toggle machine power (F2). That seems to load the changes, and any new changes just require an AXIS restart then F1, F2 again.

Having said that, my vcp panel still isn't displaying any of the values shown in Machine > Show Hal Configuration. I'm not sure what's going on there, but my guess is the pin names changed at some point (I did run sudo apt update not long ago) and I need to manually update my XML file. I'm about to check into it and will report back.

UPDATE: Something did change, as an example the hy_vfd documentation lists the pin hycomm-ok, and I've been using modbus-ok. Making that change didn't suddenly make the indicator work though, so something else is going on I'll need to look into. I'll start a new thread to dig into this further if needed.

Start Linuxcnc from the command line and you may see warnings about which pins do not exist.
I think that errors in postgui HAL files might just cause the file read to stop, with LinuxCNC staying loaded rather than erroring-out