This repository is just an edit of an existing repository that i have uploaded with changes that needed to be made to get it working as the original had some mistakes but i have made the relevant changes so you can get it working with some other handy tips if youve been strugglng like me to get this working, i take no credit for the original file as all the hard work was done by the original uploader
https://github.com/xsnoopy/LinuxCNC-Yalang-yl620-VFD-rs485-Modbus-ClassicLadder
i have just made the relevant changes as i cant message him on github or contact him on the linuxcnc forums so if you want to thank anybody thank him as i only made the relevant changes to the readme file for it to show the pyvcp panel and get the panel working and giving feedback, snoopy did all the hard work so a great big thankyou to him and here is the edited repo which i am using on linuxcnc 2.8.4 using the axis gui
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Set up the VFD drive to receive signals via Modbus.
- P00.01 = 3 Start/Stop command source RS485
- P03.00 = 4 for 19200Bps
- P03.01 = 1 RS485 slave address 1
- P03.02 = 2 Data transfer format 8 bit data, 1 stop bit, no parity
- P07.08 = 5 Frequency source selection RS 485
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Connect the VFD with your USB Rs485 adapter.
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Download vdf.hal vfd.clp and vfd.xml to your linuxcnc/config/NAME folder. Replace NAME with the name of your machine.
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Add this to "YOUR_MACHINE.Hal" file at the end ============================================================================================= loadrt classicladder_rt numS32out=100 addf classicladder.0.refresh servo-thread loadusr classicladder --modmaster vfd.clp net spindle-on classicladder.0.in-00 spindle.0.on net spindle-brake classicladder.0.in-01 spindle.0.brake net spindle-forward classicladder.0.in-02 spindle.0.forward net spindle-reverse classicladder.0.in-03 spindle.0.reverse net spindle-cmd-rpm <= spindle.0.speed-out net spindle-cmd-rpm-abs <= spindle.0.speed-out-abs net spindle-cmd-rps <= spindle.0.speed-out-rps net spindle-cmd-rps-abs <= spindle.0.speed-out-rps-abs classicladder.0.floatin-00 =============================================================================================
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Add this to your machines "YOUR_MACHINE.ini" file in the relevant sections
- Set up classic ladder with the settings from these images in the
also for people using a usb adapter that has the name /dev/ttyACM0 and hasnt added their user to the DIALOUT usergroup whis is need to get this working or configured thier adapter in linux this should help you out
https://www.waveshare.com/usb-to-rs485.htm
also to point out if you use the usb to r485 adapter linked above or any other adapter that shows up as /dev/ttyACMO as the classicladder configuration tab doesnt have this as a selectable option so to remedy this open the vfd.clp file towards the bottom you should see this text
MODBUS_MASTER_SERIAL_PORT=/dev/ttyUSB0 MODBUS_MASTER_SERIAL_SPEED=19200 MODBUS_MASTER_SERIAL_DATABITS=8 MODBUS_MASTER_SERIAL_STOPBITS=1 MODBUS_MASTER_SERIAL_PARITY=0 MODBUS_ELEMENT_OFFSET=0 MODBUS_MASTER_SERIAL_USE_RTS_TO_SEND=0 MODBUS_MASTER_TIME_INTER_FRAME=100 MODBUS_MASTER_TIME_OUT_RECEIPT=500 MODBUS_MASTER_TIME_AFTER_TRANSMIT=100 MODBUS_DEBUG_LEVEL=0 MODBUS_MAP_COIL_READ=0 MODBUS_MAP_COIL_WRITE=1 MODBUS_MAP_INPUT=0 MODBUS_MAP_HOLDING=0 MODBUS_MAP_REGISTER_READ=1 MODBUS_MAP_REGISTER_WRITE=0 _/FILE-com_params.txt
"MODBUS_MASTER_SERIAL_PORT=/dev/ttyUSB0"
(this is the line that needs editing with /dev/ttyACM0)
edit the text and save the file
when you open linuxcnc and open up the config window in classicladder you will see it has changed to/dev/ttyACM0 and it will now work also i set the vfd to 19200 8 n 1 and kept the same in the the classicladder config tab to get mine working,
also you need to add your user to the dialout group and configure your usb adapter to the correct setting
to add user to dialout group open a terminal and type this command
sudo adduser "YOUR USERNAME" dialout
then check groups for your user with this command
sudo groups "YOUR USERNAME"
and it will list the groups your username is added to
and to configure the usb adapter i installed an app called GTKTERM by again opening a terminal and typing this command
sudo apt-get install gtkterm
when installed go to applications and under accessories should now be a new application called "serial port terminal" open it up and on the configuration tab you can now change and save a permanent configuration for your adapter and any other adapter you are using. this way i had a solid connection as some people were complaining about the vfd being noisy and dropping connection, so they gave up using the rs485 method but im not using a shielded cable from the rs485 port on the vfd, it is a jst-xh 3 pin male cable thats about 20cm long. DO NOT and i repeat DO NOT BY ANY MEANS use a usb extention cable. the adapter came with a cable that has a built in ferrite and is also shielded but if i used it, as soon as i send a command to linuxcnc the connection would drop straight away. so if your trying to get this method working DONT use an extention cable for the usb adapter. also buy the adapter i listed above as people were sayin they had to use resistors to negate noise from the vfd signal to the adapter but this has them on the adapter pcb and is also lighting proof according to the specs. i tried a cheap usb adapter previously but due to a noisy signal couldnt get that working, you may be lucky but the setup is problematic enough without adding caveats yourself.