Solved - LinuxCNC does not work with new Delta ASDA-A2 drive

Hello,

I have built a rather large 3 axis CNC mill some years ago, using LinuxCNC/Axis on a standard PC, Step/Dir pulses via parallel port communication, a basic 5-axis BOB and 4 Delta ASD-A2-0743-M with Delta motors. The machine has been working reliably for some years, and although aware of the limitations of this setup, I was quite happy with it. Then one of the Delta drives failed by the end of December, and I'm now trying to fit in a replacement part.

The new drive is the same, brand new, exact reference. I was able to swap the unit and plug it exactly like the old one. I had a back-up of the parameters file last in use on the old drive, that I have uploaded to the new drive with ASDA Soft 5.5.0. I got a warning that the firmware on the new drive was more recent than that in the file (V4,052, Sub:2 ---->>> V4,061, Sub:340), and the soft offered to upgrade the file before uploading it. In the end, it seems that 2 parameters (P2-95, P2-97) were added, with default values.

Problem is that I can get the axis moving through the JOG screen in ASDA Soft, but not with LinuxCNC jog : the position displayed on the screen changes, but the machine's axis does not move, and the motor makes no noise at all (there is no feedback from the drives to LinuxCNC due to parport limitations).
When I have tried to Home All axis, the Z (vertical) and X (gantry, 2 drives/motors) were OK, but the Y axis, that of the new drive, keeps "moving" virtually on the screen while nothing actually happens on the drive (?) and motor.

I think, but I'm not quite sure, that the machine's axis moved on the very first attempt, albeit in the direction opposite to expected.
I dont' get any error code on the drive's panel, and no errors in LinuxCNC either.

I have probably missed something basic, but I can't figure out what. Any idea ?
Thank you for reading this far, any help is appreciated.

Hello @tommylight, thank you for your suggestion.

I'm off the machine at the moment, and working through the Delta documentation and build notes from back then. I suspect that the backup parameters file might be wrong, I'll check tomorrow by downloading the X axis parameters first to compare.

Thanks again

M drives are Can bus. They can be switched to analogue or pulse though. Most likely it is defaulted to Can bus operation.

Hello,

Got the drive working again today, the parameters for Control Mode and Pulse Type were indeed wrong (so you were both right

Turns out that my backup parameters file was not good at all, I ended up just copying the working parameters from one of the X drives to the new Y drive. Both axis have the same mechanical setup, gear reduction ratio etc...

@ihavenofish : you are right, these drives have CAN bus capability. I made this choice at the time as I was not quite clear about the various options. Now, I wish I had chosen the E version that offers EtherCat...

I'm thinking about upgrading the whole setup to EtherCat, possibly running LinuxCNC from a RaspBerry. Pi. That would allow me to get rid of the PC/Parallel Port limitations, move all the hardware inside the control cabinet, and have more I/O to finally add some extras to the machine.

Thank you all for your help, great to see this community thriving !

cool.

downside to the ethercat is its ONLY ethercat. i wish it has pulse as well. would be more versatile.

> downside to the ethercat is its ONLY ethercat. i wish it has pulse as well. would be more versatile.

That's right. Now I remember that this is what pushed me to choose the M version. It seemed to me at the time that the pulse/dir was the simplest method, so it was less risky for me (this machine was my first build), and I paid some extra to get another option for the future. Turns out that CanOpen does not seem to be a viable option with LinuxCNC, but well...

If EtherCAT works well, wouldn't it make the pulse option look rather outdated ?

(Still need to do a lot of reading before I can consider an upgrade to EtherCat)

ihavenofish wrote:

cool.

downside to the ethercat is its ONLY ethercat. i wish it has pulse as well. would be more versatile.

It does if you use an Ethercat stepper driver. There are many. I use rtelligent ECT86

talking specifically about delta servos.

"If EtherCAT works well, wouldn't it make the pulse option look rather outdated ?"

basically yes. pulse and analogues went out of date in the mid 90s and everyone went separate ways with serial protocols. Pulse stuck around for hobby people but the dust has settled now and ethercat is the way forward for sure.

Whether it is your present depends on a lot of factors. Usually money