[ Vfdmod ] An easy VFD control over MODBUS RTU

ok one step more
it's look like :

Opening /dev/ttyUSB0 at 9600 bauds (N, 8, 1)

vfdmod: reading 'spindle.rpm-out' from address 8203 (0x200B)...
[01][03][20][0B][00][01][FE][08]
Waiting for a confirmation...
<00>
vfdmod: setting command speed value to 5 (0x0005)...
[01][06][20][01][00][05][13][C9]
Waiting for a confirmation...
<00>
vfdmod: reading 'spindle.rpm-out' from address 8203 (0x200B)...
[01][03][20][0B][00][01][FE][08]
Waiting for a confirmation...
<00>
vfdmod: setting command speed value to 5 (0x0005)...
[01][06][20][01][00][05][13][C9]
Waiting for a confirmation...
<00>
and so on ...
but the minimum speed is correctly written to the inverter - it changes from zero to 5

Try to increase ProtocolDelay to 5...15 and watch to debug, is something changes?

After increasing ProtocolDelay, ignored replies from random senders show "The responding slave 127 isn't the requested slave 1 , ...,
The responding slave 217 isn't the requested slave 1 "and after several such replies return to " ERROR Connection timed out: select. " Only the read request 8203 and write 8193 is sent. The minimum frequency is correct.

I changed the converter to yours and now the debug out looks correct - next commands and the inverter answer, but the running program still shows connection errors and you can not control the direction or rotation

Error code for RS485 is 112345679 and diode is RED

No returned value after this block, it seems like my read coils function works wrong. Try to delete "user-coil-parameter" parameter from your ini.

You are genius
I deleted this fragment and made my-pyvcp-panel.xml file and postgui.hal file again. The connection is green and no errors
I'll check the rest in the evening because work is waiting. Thanks again Aekhv

Communication is ok but no reaction to traffic commands. The "Spindle at speed" diode is red and there is no reaction to start and stop and RPM setting. Information about the minimum revolutions is sent to the inverter, but only the revolutions without a movement command - the display on the inverter blinks with value of minimum

Well, possible reasons are:
a) wrong control register address and / or wrong control world values. See your device manual to be sure.
b) wrong HAL connections. Show your HAL files please, I'll try to help.

I think the registers are ok - sending the value 0x0012 to the address 0x2000 causes the start to the right, etc.