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Hello! First of all I’m sorry if this is placed in the wrong category. I’m pretty much new to Linux and LinuxCNC and been busy building a CNC mill but I’ve stumbled up on a lot of problems. 

My first thought was to get some help by using AI (Copilot) to configure Linux CNC but it doesn’t work that well because info online is limited on 2.9.4 so the AI is trying to use solutions that’s outdated for previous versions of LinuxCNC. 

The progress I’ve made so far is to configure and flash firmware to 7i95t with MesaCT and edit hall and ini files to run QTdragonHD and get the stepper motors to move but then I wanted do add 3 MPGs to jog each axis. 

Well that didn’t work that good.. these are the things I hope to accomplish one day: 

1. X-Y-Z MPGs with incremental and continuous movement. 
2. E-stop circuit (input) with reset. 
3. Add limit switches 
4.Closed loop feedback by using glass DRO scales. 
5.Spindle control 0-10v VFD or just relay control. 
6. Inputs/physical buttons: cycle start, cycle stop, 3 position resolution rotary switch for MPGs, 
7. Joystick (switches) to feed X and Y. (Like a power feed on  a manual machine) with a potentiometer to adjust feed rate) 
8. Output for fogbuster/flood coolant. 
9. Output for Compressed air nozzle. 

The list is long, 

I don’t know where to go from here.. 

Errors I’ve got earlier is missing motion.so and other modules, I’ll post the basic ini and hal files to.
 

I have had a good look through the manual, unfortunately, no tuning software but i have looked at these parameters and looks like they can help.

P08-00 Speed loop gain.
P08-01 Speed loop integral time constant
P08-2 Position loop gain
P08-15 Load inertia ratio
P08-19 Speed feedforward gain

Master is 2.10

So you would need to build from source or get a snapshot from the buildbot
to update to master.

BUT... you should be able to just replace the current pncconf pieces with these:

forum.linuxcnc.org/39-pncconf/56464-mesa...thcad-pncconf-screen

( Thanks kworm )


Another option is MesaCT which has had 7I95/7I95T support for a long time.

 

Yes, the AOUT voltages should be very close to 0.0V
at startup, 3.3V suggests a damaged OP amp
or a local (on card) power supply issue.

May have been damaged by a voltage transient.
Plasma tables generate large transient voltages when the
arc starts and stops. This is due to the almost instantaneous
start and stop of current flow.

This means system grounding is very important. It may be
that the PC ground path was enough different from the machine
ground path to cause this kind of damage. This might have been
prevented by having the controlling PC in the electronics case
with the servo drives, or using the 7I77ISOL card to completely
isolate the 7I77 ground from the PC.

Another possible cause of this kind of damage is a problem with the
7I77s 5V power supply. A voltage surge on the 5V supply can damage
the analog power supply and have similar symptoms.

Do the 2 yellow LEDs in the center of the 7I77 card light?
(these monitor the + and - analog supplies)

I should note that it's probably repairable
 

kjlty wrote:

"I would greatly appreciate it if you could replace QPlainTextEdit with QsciScintilla."
 

What is the advantage of QsciScintilla?
Is that a native QT widget?

JT

thanks, will test that.

btw - I have installed the latest release of the linuxcnc debian - 2.9.4 - and there is no 7i95 option, is the version on master newer but not released?

I changed the 5v psu for a 5.2v one. I am seeing 5.03v on the TB1 now. But same jolt and stop issue.
What do you think of the aout0 and aout1 voltages? Is that what you mean by damaged?

The most common issue with lack of motion ins step/dir systems is too short
pulse width settings. I would always start with at least 5 usec (5000 ns)
for the step pulse length.

Another common issue is insufficient drive, which is why its suggested to wire 
opto-isolated step/dir drives in single ended format as this reduces the drivers
source resistance by 1/2.

Single ended:

7I95        DRIVE

STEP+    PUL+
DIR+       DIR+
GND       PUL-,DIR-

The PID setup is intentional.

Note that the latest pncconf ( in LinuxCNC master ) has direct 7I95/7I95T support

 

You are welcomed, always.

forum.linuxcnc.org/show-your-stuff/47357...hines?start=0#256463
Attached Messer_big is for 7i95 (not T) and uses encoder feedback and is for plasma, so just take it as a reference to compare to.

I’m trying to test run my new Mesa 7i95t. I am completely new to LinuxCNC but have lots of CNC (and programming/linux experience FWIW). Before I start touching anything in my DIY machine (currently running on FluidNC) I just want to get a single stepper driver to run a single stepper motor so that I can complete the flow end to end. As a sanity check I’ve hooked up a DM556 stepper driver to the card’s stepgen 03 connector (tried both a differential connection and also just connecting PUL- and DIR- on the driver to stepgen’s ground). The stepper driver is powered by a 24v PSU and works perfectly if I just connect its PUL to a pulse generator. The ENA is left unconnected, enabling the driver. I’ve setup the Mesa config with pncconf using 7i76 as the card and then later switched to hm2_7i95.0 in the INI as per the instructions. Assigned stepgen 03 to the X axis. LinuxCNC starts fine, I can unlock the machine and jog, and see the DRO changes values - but the stepper doesn’t move. Looking into the generated HAL file, I see control type set to 1 (velocity and not position? does this make sense for a stepper driver like this)? Also, I see a bunch of pid initialization, and again it’s confusing to me why PID is needed for an open loop stepper driver that provides no encoder feedback to LinuxCNC. What am I missing here? Is there a sample HAL file that works with the 7i95t and a simple open loop stepper driver that I can test? Thanks!

That likely means the 7I77 has been damaged
(or perhaps has very low 5V)

 

With mesa powered and linuxcnc not started aout0 shows 2.8v and aout1 shows 3.3v.
These are the pins going to the drives. On the other free pins we get 3.3v. This is TB5
On TB1 (5v) I get 4.75v. TB5 is powered from the computer psu.
By the way this setup already worked and we did cut 12mm sheets.
On TB8 outpus I don’t see any voltage. I will post the ini and hal file later.
If you have any other debugging steps I’m all ears.
With aout0 and aout1 disconnected when I enable the machine there is no jolt since drives are disconnected but I still get the same error.

I would think the simplest option would be a used PC with a parallel port
and one of those "Mach 5 Axis" parallel port breakouts. 

For a small amount of 5V, a safe option is to just use PC USB power
(which is what the "Mach 5 Axis" BOB does)

The mouse issue sounds like EMI so likely a grounding/line filter issue with the servo drives

Ethernet is much more EMI resistant than USB so that may be a latency issue.

To check network latency, run this:

sudo chrt 99 ping -i .001 -q -c 60000 [card_ip_addr]

Where [card_ip_addr] is either 192.168.1.121 or 10.10.10.10 depending on the 7I76E settings

This will run for 1 minute and print timing statistics