Help with pinout. 2 motors (joints) on one axis. 2.8

Todd wrote:

(and more opportunity to confuse yourself or make mistakes).

Or opportunity to learn something new and make it neater.

LOL

I had been thinking the wrong thing for a short time. I thought with Stepgen.0 the 0 related to the joint. It doesn't so I'm lost again.

As I said, the "signal-name" can be anything. the signal-name is referenced to a source and then signal-name is referenced to a pinout. I have found how the signal-name is referenced to stepgen but that's just the step type not which joint. There must be a way to reference a signal-name to a joint. Just haven't found it.

Still looking.

To see what is controlling a stepgen you have to look at what the stepgen's inputs are connected to. Look for a pin named "stepgen.0.position-cmd" (or possibly "stepgen.0.velocity-cmd") for the one controlling stepgen.0. That will be connected to a signal (of any name) then you have to find what output pin controls that signal. It is most likely "joint.0.motor-pos-cmd", but it could also be any number of other things.

Todd wrote:

To see what is controlling a stepgen you have to look at what the stepgen's inputs are connected to. Look for a pin named "stepgen.0.position-cmd" (or possibly "stepgen.0.velocity-cmd") for the one controlling stepgen.0. That will be connected to a signal (of any name) then you have to find what output pin controls that signal. It is most likely "joint.0.motor-pos-cmd", but it could also be any number of other things.

That's exactly what I'm looking for. Thanks

I'll play with my configs when I get home from work.

Hey Rodw,

I think you mentioned somewhere that many use XYZA in Stepconf then change the config files. That's going to be a bit confusing as well as stepconf creates the A axis as a rotary axis.

I still think it's going to be easier just to create XYZ, copy and paste one of those axis and make appropriate changes. One for me will be bumping along the joint numbers as XYZ will be joints:

0 = X
1 = Y
2 = Z

I will make it joints:
0 = X
1 = Y
2 = Y
3 = Z

By the way, I got my first stepped motor to run from my computer late Thursday night. By Friday morning, I had it running up to calculated 400mm/Second before it stalled. My ball screws wont handle anywhere near that so it's good to know the motors, drivers or computer wont be anything to slow down my travel speeds. The max rpm for the ball screws are going to be my limiting factor.

Happy Days

joel0407 wrote:

Hey Rodw,

I think you mentioned somewhere that many use XYZA in Stepconf then change the config files. That's going to be a bit confusing as well as stepconf creates the A axis as a rotary axis.

I still think it's going to be easier just to create XYZ, copy and paste one of those axis and make appropriate changes. One for me will be bumping along the joint numbers as XYZ will be joints:

Yes, thats what I did. The sooner you get your head around hand editing hal and ini files the better I reckon!

rodw wrote:

The sooner you get your head around hand editing hal and ini files the better I reckon!

Yep, agree. I find it difficult with the manual trying to appease both audiences, the GUI and the command line. The GUIs aren't up to scratch at all for 2.8. They seem way behind. It's pretty evident with the first option for machine configuration in stepconf where it only gives 4 options (I think, at work and don't have it in front of me). There is no option for anything with 4 linear axis. It's pretty limited to standard basic cnc machines.

Happy Days

Hey guys,

I'm getting there. My problem now is, if I have anything other than

[KINS]
JOINTS = 4
KINEMATICS = trivkins coordinates=XYZA

in my INI file. I have problems.

If I have:

[KINS]
JOINTS = 4
KINEMATICS = trivkins coordinates=XXYZ

I can't get movement on the X axis

Or

[KINS]
JOINTS = 4
KINEMATICS = trivkins coordinates=XYYZ

I cant get movement on my Y axis.

When I run LinuxCNC. Which ever axis is not working is just skipped. If X is not working, left and right keys do nothing, Up and Down move the X axis and Page Up and Page Down move the Y axis without the Z.

Same if Y is not working, X keys move X, Y doesn't move with up and down keys but it does with page up and down.

You can't jog a slaved axis until after it is homed. (This is because they are not really slaved together until after homing is completed.)

Todd wrote:

You can't jog a slaved axis until after it is homed. (This is because they are not really slaved together until after homing is completed.)

Thanks Todd,

I'll have another crack when I get home in the morning (at work now).

Makes sense but I'm surprised that the jog skips it with the controls. So once it's homed, will it return to normal jog controls, arrow for X and Y then PGUP and PGDN for Z?

Jogging is disabled for the doubled axis, because trying to jog it would only move one side, racking your gantry. For this reason a gantry must have automatic homing configured for the master and slaved joints at a minimum.