Starting over

I purchased a three axis kit with 4 steppers, 4' by 8'. Two on the X, one on the Y and the Z. I have it together and am installing limit switches on all the axis extremes. I don't have a router yet.

I bought a Mesa 5i25 and G540 before I'd thought it though.Linux I know but learning Linuxcnc, the Geko and the Mesa was a bit more than I expected. Not knocking them but I've since read of a lot of other frustrated guys fighting that config and having problems getting the HAL and INI worked out, especially on a 4-axis machine with a lot of switches.

I am not married to either the Mesa or the Geko. I would like to discover and use the hardware which has mature config files and best support within the forum. I realize I could get my existing hardware working after I do endless edits and hammer the forum with questions while you teach me esoteric HAL programming but I'd rather swim with rather than against the tide.

Which config is the most robust and best supported within the group? What hardware does it expect to interface too?

Patrick Obrien wrote: Which config is the most robust and best supported within the group? What hardware does it expect to interface too?

Probably parallel port and G540.

And that might be the way to go. Set up for a G540 with stepconf and the parallel port. Then swap the parallel port for the 5i25 when you feel more comfortable with the rest of the system.

You don't have a 4-axis machine, you have a 3-axis machine. You can just connect X-step and X-dir to two pins each on the parport in stepconf.

Eventually I would suggest installing the 5i25 and upgrading LinuxCNC to 2.8 where support for systems with more than one motor per axis are significantly better supported.

Or, just hammer the forum with questions, it helps us feel useful

I thought about the wiring shortcut but then remembered how many ways I could regret that. Just me.

Ok question one. I don't recall a global for the interface,something like

interface = parport
# interface = 5i25

so there must be a config rewrite. I looked through the forum but didn't find a guide.. If there is a form reference I missed, let me know.

Have you tried running PNCConf?

Not in a while. I recall it wanted an 5i25 with another mesa card. G540 was not an option.

Is the 5i25 flashed for the G540?

www.mesaus.com/info/mesaflash.html

The biggest problem people have are with the charge pump on the G540 which can be turned off.

If you have a lot of I/O you might consider a 7i76 or a standard breakout board attached to P2.

JT

Patrick Obrien wrote: Not in a while. I recall it wanted an 5i25 with another mesa card. G540 was not an option.

Because the pin allocation is set in firmware, and not HAL, it turns out that the HAL code is almost (and sometimes exactly) the same even if the firmware and physical pins change. So you can use the settings for a probotix breakout as long as your actual firmware is G540.

So, in PNCConf choose the 5i25 internal data and prob_rfx2 option (which is a simple dumb breakout). and choose "accept component changes"
Then configure connector 3. (which is the DB25 connector on the 5i25) and you will see "unused stepgens" numbered 0, 1, 2 and 3. Choose axes for these to suit how you want to wire the G540, for example 0 = X, 1 = tandem X, 2 = Y, 3 = Z.

I think that GPIO 000 is charge pump on the G540? If so then choose GPIO 000 as control-> charge-pump

This setup should be really very close:

Having followed this through, I see that you can't change the PGain fro 50 for the stepper PID. Is that the right number?

BigJohnT wrote:
Is the 5i25 flashed for the G540? The biggest problem people have are with the charge pump on the G540 which can be turned off.

If you have a lot of I/O you might consider a 7i76 or a standard breakout board attached to P2.

It came that way and I've redone it several times. I'm not against either but I get into trouble doing configuration tweaks. My logic was to use what everyone else is using on an 4 motor 3-axis and avoid the hole most rookie tweakers fall into.

I would love to have an I/O problem. Not there yet.

andypugh wrote: ... you can't change the PGain from 50 for the stepper PID.

You lost me there but I will give the above a try.