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

I believe everything is arbitrary but have not used a par port. (other than to make my own crude breakout board 30 years ago for an animated window display that won me some nice crystal glasses)

If you have a look at this post on the other thread
forum.linuxcnc.org/49-basic-configuratio...lease?start=20#96019

This is the only fixed bit - the LCNC stepgen
And through this construct, you can send the stepgen output to any parport output pin

I think this is what makes LinuxCNC so flexible. You can do almost anything.

What each pin on the parallel port is used for is completely arbitrary up to the point that inputs must be inputs and output must be outs. But what each in or out does is completely up to you. There are also 3 different configuration options for the parallel port driver that give different combinations of ins and outs. Configured as OUT (default) gives 5 inputs and 12 outs, as IN gives 13 inputs and 4 outs, as X gives 9 inputs and 8 outs. There are breakout boards that support both the In and Out option, but I do not know of any that work with X. Also note that not all parallel ports support X mode, and that the port usually has to be set to SPP mode to use it. linuxcnc.org/docs/html/hal/parallel-port.html

I still think it would be slightly simpler to set up XYZY rather than XYYZ. But in the end it doesn't really matter, it can be set up either way. Just little more hand editing one way than the other (and more opportunity to confuse yourself or make mistakes).

Part of what makes Linuxcnc so powerful, is its flexibility in how it can be configured. This also is what makes it so complicated to set up. It is not locked into specific pin assignments or combinations for anything, unlike some other controllers.

Todd Zuercher 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 Zuercher 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