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Yes, that is correct.

Axis GUI?
Did you accidentally press the 0 on the keyboard? That would set the feed rate to 0 and would do exactly as you describe, namely start and go to the first cut and stop there waiting.

I will try that tommorrow , There is no real Identification on the PC, Small Black Box , Has a Motherboard and a Hard drive only.

It wasn't spindle at speed, I had checked that first thing. It wasn't the M0 pause, I had tried running it with that line deleted with the same result. Starting the program rhe machine would raise the spindles, start the spindles, move to the starting point, lower the spindles down to 0.25, and pause, At this point clicking the pause button or pressing the next line buttons would have no effect. I tried debugging the parameter that was setting the feed rate before Line 20, and it was what it was supposed to be. I tried deleting the parameter for the feed and expicitly setting the F term with the real feed number, no effect. Deleting the M0 only changed that the pause button on the menu bar wouldn't toggle on, but the machine still would not proceed beyond line 20.

I still don't know what the real problem was, but I restarted the Linuxcnc from the command line to try to see if there were any messages there, and then it ran fine. weird

Hi Everyone,

I have never setup a CNC machine before, so while I found many other people's posts on similar topics helpful, I'm still not confident enough to try it myself without asking someone if I have it correct. I have a 7i96s board, and I can see that the TB2 PINs 22,23,24 are as follows.

22 - SPINDLE-
23 - SPINDLE OUT
24 - SPINDLE+

And the below image is my VFD's pinout


From this I gather the following

22 - SPINDLE- to COM
23 - SPINDLE OUT to AI1
24 - SPINDLE+ to +10v

Is this correct? I also wanted to know how to control the direction. Thank you for being so helpful.

Gautham

 

In this mode it uses a Renesas ISL32173 chip to take in the differential signal through what amounts to a comparator and output a logical signal to some counter in the FPGA. The issue is that the chip is designed to be really sensitive and a differential signal over 0.2V is considered high. That is nuts on a signal that is 3.3V or 5V differential.

200mV diff voltage threshold comes from the EIA-422 standard. i believe every compliant receiver IC does the same. nevertheless, usually they perform nicely in pretty harsh noise environment. i suspect your "backpack" may be a problem, not the 7i76

You could consider adding this to the Wiki too.

wiki.linuxcnc.org/cgi-bin/wiki.pl?ContributedComponents

Here is how to edit a wiki page:
wiki.linuxcnc.org/cgi-bin/wiki.pl?BasicSteps

FWIW the penguin is called "Chips" (though I don't recall if he capitalises his name)

So I found the AXIS Gui document and if I apply the pins described there to your MPG code, it should be about this

# Set jog-vel-mode to false (joint will move exactly jog-scale units for each count)
setp joint.0.jog-vel-mode 0
setp joint.1.jog-vel-mode 0
setp axis.x.jog-vel-mode 0
setp axis.z.jog-vel-mode 0

# Set jog scale 
setp mpg-scale 1.0
net  mpg-scale joint.0.jog-scale axis.x.jog-scale <= halui.axis.selected.increment
net  mpg-scale joint.1.jog-scale axis.z.jog-scale <= halui.axis.selected.increment

# Joint selection (enable only one at a time)
net mpg-select-x joint.0.jog-enable axis.x.jog-enable <= halui.axis.selected.0
net mpg-select-z joint.1.jog-enable axis.z.jog-enable <= halui.axis.selected.1

# Connect encoder counts to all joints (only enabled one will move)
net mpg-counts  <=  hm2_7i80.0.encoder.03.count
net mpg=counts  joint.0.jog-counts  axis.x.jog-counts
net mpg-counts  joint.1.jog-counts  axis.z.jog-counts

Is this how it could work to use the AXIS-GUI pins instead of an axis and a increment selctor switches?

Sigi

I think I got to the bottom of it. There were some locations I could twist the spindle (and hence spindle encoder) to manually that resulted in continued increases or decrease of the spindle position. This told me it was still noise so I dug into it.

I have no idea why, but on the mesa 7i76 the encoder input can be differential or single ended. I was using it in differential mode because I thought it would be more noise immune. I also had a "backpack" sort of thing on my encoder that made the single-ended outputs 3.3V differential. In this mode it uses a Renesas ISL32173 chip to take in the differential signal through what amounts to a comparator and output a logical signal to some counter in the FPGA. The issue is that the chip is designed to be really sensitive and a differential signal over 0.2V is considered high. That is nuts on a signal that is 3.3V or 5V differential. Hence, despite all my work it was still noise, but I decided to just go back to 5V single-ended at 5V directly out of the encoder and now all is well... despite the noise levels being higher in absolute terms the signal to noise ratio is much much better and I can cut perfect threads! (Yeah I had my scope on it a lot throughout this.)

I don't know why there is no warning in the datasheet about this. 200 mV of noise on a 3.3V-5V signal should NOT be causing this kind of issue. Typical levels of a high bit on 3v3 logic is >2V. I think for some reason they used an RS-422 chip and it was not the right choice in my opinion... especially without a giant flashing warning.

Maybe I'll mention this to Peter at mesanet. They make a great product... but I think this was a bit of an oversight.