[ Vfdmod ] An easy VFD control over MODBUS RTU

Hi

Relative newcomer though I am, I have implemented a couple of 3-axis machines interfaced via parallel port to the stepper drivers and RS485 to the vfds. The first used the HY-01 vfd and the associated inbuilt LinuxCNC driver. The second system uses the H100 vfd, with VFDMOD as the driver. These systems used old 64 bit AMD based PCs. I have decided to upgrade to MESA 7i92T and purchased one a month or so back, I also received a RPi5 in the post around the same time and decided it would be a more compact solution and could be fun to implement RPi5 + MESA 7i92. The interfacing to the steppers/switches was straightforward once the manual had been decoded (!) and the CNC is now functional. The modbus interface to the pi is causing me problems - as RPi5 is 64 bit only, and the VFDMOD release for the pi is 32 bit armhf. Can anyone give me pointers on implementation of VFDMOD on the RPi5? Is anyone else out there doing a similar thing?

You were right, VFDmod works with G96, it's all in how the different spindle and vfdmod pins are connected, unfortunately there are no clear examples of lathe configurations with this component.

Pickle, I can only speak for myself, but for me it it was to much hassle to get VDFMOD working on a PI. I just used a standard component of Linuxcnc: MB2HAL. linuxcnc.org/docs/html/drivers/mb2hal.html
Your VFD looks well documented. First look for modbus capability's, does it support:

read_coils
read_discrete_inputs
read_holding_registers
read_input_registers
write_single_coil
write_single_register
write_multiple_coils
write_multiple_registers

Work with the ones your VFD supports. Look for examples,  ask some questions, don't expect it will be easy, and be happy

Thanks for your input. I tried with mb2hal first with my H100 vfd on an old (sempron) pc, but couldn't get anywhere, hence the switch to VFDMOD. To my mind the "user manual" for mb2hal is not written for the uninitiated! The VFDMOD instructions were easy to follow and once I had decoded the H100 manual the implementation on PC was straightforward.   I have revisited MB2HAL for the Pi5/arm64 but I cannot get my head around it - mental block.  I could (and may have to)  go back to the PC and implement VFDMOD alongside the mesa 7i92 on that, but solving the RPi5 implementation is a challenge I don't want to fail on! 
Perhaps - and I realise it is a big ask - you could share your config files to give me another view on the implementation?


 

I don't know if anybody uses VFDMOD on a PI. I'm not a Linux-guru. It is indeed easier. The manual of MB2HAL is....... and you can't do calculations (scaling) within MB2HAL. So you have to do that in your HAL-files.

Here you see me struggling.  On page 2 I share my files. They are not well documented, you can probably just copy/paste it and change your modbus addresses. If you had a working VFDMOD config, you are very close

I had to use my PI because my 7c80 requires it, but if I had an other interface I would just use a PC.... well, a PI5 is nice.....

 

Thanks....you are a star! If I have any success I will post here....