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Occasionally, when using 'run' on the 'Test/Tune Axis' panel, for a back and forth test of 2", the movement at the end of travel oscillates around the endpoints. It isn't consistent, it will oscillate for a little bit and then stop oscillating and then start up again. I will try and post a video of this shortly. Any insight would be greatly appreciated!

This typically means that the P term is set too high in the local PID control loop.
For local control loops, P should be set to 1/(servo period in seconds), That is,
1000 for a 1 ms servo thread period or 500 for a 2 ms servo thread period.

The physical meaning of this P term setting is that any detected position errors
are corrected by the next servo thread invocation.

@ccatlett1984
Do not change the subject tittle as it makes it impossible to find when searching.
Thank you.

On the latest Linuxcnc images SPI should be enabled by default, this was an issue I had with the previous releases.
You specify which spidev mesaflash uses on the command line switch as the --addr, spix can be forced to use a particular SPI interface. The Linuxcnc docs for spix are a good read as it points everything out.

Many thanks to everyone who has offered some advice. I found a single stepperonline DM860T stepper driver on marketplace to test with and I now have the x-axis wired to my 7i96 for and moving, more-or-less as expected. I have the driver and Mesa card wired for differential inputs (dir +/- and step +/-). For settings, I'm simply using 5000/5000/10000/10000.

 

For what it is worth, the timing page in the stepperonline manual lists:

• dir must be ahead of pul by 5000ns
• pulse with not less than 2500ns
• low level width not less than 2500ns
  
  
  Two quirks I've noticed:
  1. The max limit for direction hold/setup in the 'Test/Tune Axis' option is 10000, rather than the recommended 20000.
  2. Occasionally, when using 'run' on the 'Test/Tune Axis' panel, for a back and forth test of 2", the movement at the end of travel oscillates around the endpoints. It isn't consistent, it will oscillate for a little bit and then stop oscillating and then start up again. I will try and post a video of this shortly. Any insight would be greatly appreciated!

RPI5 OS with 7c81 Interesting note:
- Leaving config.txt alone creates only spidev10.0 and hal_spix works fine, but mesaflash does not.
- Enabling spi in config.txt (dtparam=spi=on) creates spidev0.0, spidev0.1, and spidev10.1, hal_spix works fine, and mesaflash works fine with --addr /dev/spidev0.0

It would appear that hal_spix just looks for the first spi device, whichever one it is, or scans all of them; and mesaflash explicitly requires it to be on spidev0.0.

Peter? 

Hi, I'm trying to setup an ATC carousel with "style" I could have added an axis and use the standard probe basic marcos but the carousel component is something I would like to learn. 

1) I tried to feed the carousel.0.count-target straight as a pos-cmd getting a following-error, guess due to the sudden change in position, the motor moves a bit then stops with an error.
2) as a second attempt I've added a joint (without axis) to feed the new servo position from joint.N.motor-pos-cmd hoping that the servo would be controlled as an axis but motor.pos.cmd is an OUT pin..

At this point I'm lost, but don't want to give up using an axis, any suggestion?

Attached my actual toolchange.hal