yalang yl620 VFD rs485/modbus communicaiton

OK got it working. Cleared all the configs, started again. Used Classic ladder this time and it worked first try.

Take a look at this

Hi,
Not sure if this is the correct topic to ask this, or whether I should post it in the VFDmod thread at:

• forum.linuxcnc.org/24-hal-components/387...trol-over-modbus-rtu.
  
  
  I'm a noob LinuxCNC setting up for the first time and want to control my 220V 2.2kW 400Hz water cooled spindle over rs485 modbus.
  
  I have installed VFDmod (as per instructions at github.com/aekhv/vfdmod), and then proceeded with the instructions given on xsnoopy's yalang yl620 VFD rs485 modbus page at:
  • github.com/xsnoopy/LinuxCNC-Yalang-yl620...s485-Modbus---VFDmod
    
    and also changed my VFD settings as instructed, but LinuxCNC errors out with:

       Debug file information:
        Note: Using POSIX realtime
        vfdmod: Permission denied
        vfdmod: fatal error.
        ./custom.hal:4: waitpid failed vfdmod vfdmod
        ./custom.hal:4: vfdmod exited without becoming ready
        5203
        Stopping realtime threads
        Unloading hal components
        Note: Using POSIX realtime
    
    Full LinuxCNC Error Report attached.
    
    Can anyone see where I've gone wrong or suggest a fix?
    
    Thanks,
    
    Phil.

Thanks Andy, adding the user to the "dialout" and "tty" groups fixed the problem.

Next problem: It's now erroring out with:

"pyvcp_options.hal:8: Pin 'pyvcp.spindle-speed' does not exist."

I imagine there's a simple fix, but I don't want to break anything by randomly applying my own fixes! Any help/suggestions are welcome.

Phil.

Ignore my last message - after a bit more fiddling around (setting up a fresh mill configuration in StepConf) it all seems to work now! Fingers crossed.

Just a quick addendum for anyone setting up an RS485 Modbus PC->VFD link: I found it necessary to add a 120 Ohm resistor to both ends of my screened twisted pair cable. Without the resistors, LinuxCNC doesn't always see the RS485 connection and throws a error. As soon as I added the resistors, the connection was stable.
More here: www.analog.com/en/technical-articles/rs4...axim-integrated.html

hey david can you post your files that you used to get this working as ive done a fresh config with stepconf using classicladder but the pyvcp panel doesnt respond, the gauge doesnt move and the spindle at speed and rs485 indicator are red so i dont know what the problem is but i get a stable modbus connection to the vfd and can run and stop the spindle with the plus and minus buttons in axis gui,

yalang and huanyang are not the same VFD