drivers for waveshare RS 485 usb serial converter for huangyang vfd

loadusr -Wn vfd hy_vfd -n vfd -d /dev/ttyUSB0gives error:

ERROR Communication time out (-12)
error reading setup from VFD, retrying
WAIT_DATA(): comms time out

loadusr -Wn vfd hy_vfd -n vfd -d /dev/ttyUSB0 -r 19200 -b 8 -p none -s 1 -t 1 -g Gives new errors: 

vfd: device='/dev/ttyUSB0', baud=19200, bits=8, parity='none', stopbits=1, address=1, debug=1, PID=2733
Opening /dev/ttyUSB0 at 19200 bauds (none)
read_setup: reading setup parameters:

query_length = 6
hycomm query = [01][01][03][05][00][00][2C][4F]
query_ret = 8
response_length_computed = 8
waiting for message (8 bytes)...
read 1 bytes:  0x00
message was incomplete, length still to read = [07]
WAIT_DATA(): comms time out

ERROR Communication time out (-12)
read_setup: FAILED
error reading setup from VFD, retrying

Ground wire connected, makes no difference in anny of the three " loadusr" lines.

No one has any thoughts?

SvenH wrote:

No one has any thoughts?

Not me, sorry.

In reading over the product page www.waveshare.com/wiki/USB_TO_RS485

It mentions:

Question:What should I do if the RS485 short-range communication is abnormal?
Answer:
Remove the 120-ohm termination matching resistor from RS485.

Is that something that I might try?

SvenH wrote:

The bits that seem to matter:

Code:

xhc-hb04.tcl: !!! <halui.spindle.stop> target pin does not exist, continuing xhc-hb04.tcl: !!! <halui.spindle.start> target pin does not exist, continuing

I think that this might be important too.

It appears that you have updated from 2.7 to 2.8+ and there are hal pin name differences between the two as LinuxCNC now supports multiple spindles.
linuxcnc.org/docs/2.8/html/getting-start...iple_spindle_support

It says there that the update script will fix the hal pin names, but you have found a gap in the coverage, as you seem to have a custom xhc-hb04.tcl file in your config? The updater script only fixes HAL and INI files.

Try editing that file so that halui.spindle.start is halui.spindle.0.start and the same for spindle.stop.
linuxcnc.org/docs/2.8/html/man/man1/halui.1.html

I think that this might be the only problem, the hy_vfd module does send a lot of spurious error messages before it is enabled.