Starting from scratch (again) - need help (apparently a lot)

OK, failed miserably twice, now starting over right from scratch...

Building a new control for an existing lathe conversion that's running mach3.
Simple X and Z axis steppers, both using G203v drives
x limits (+ and -) and z limits (+)
E-stop button (one on the control and one on a wired remote)
Spindle is run off a 0-10v controlled VFD (Minarik)
Shuttle express for a pendant
Control board is a c11g, c6 spindle encoder for threading

Anyway, for various reasons, wanted to change to linuxcnc
I have a 6i25 card I purchased a couple of years back (and tried to get running but failed) and a 7i76 that I purchased after that but only now am attacking this again

I'm attempting to get this running on the bench without touching the existing setup since it didn't go well last couple of times
I have a 24vdc power supply
2 small nema 23 steppers
2 older tormach drives (they are gecko 201 clones)
one fresh computer with a new linuxcnc install (2.7.14)

6i25 card is installed and is providing 5v to the 7i76 card
mesaflashed the card with what I believe to be the correct bit file (5i25_7i76x2.bit 2018-12-19)

7i76 card is wired via a DB25 cable (checked that the ground pins are separate)
W2 in the left position
24vdc connected to TB1, + on pin1, gnd on pin 8
W1 in the left position

W3 is in the left
W4,5 and 6 are in the right

CR1 light is on with the computer and CR2 light is on with the 24v power supply

Connected one stepper drive to pins 1, 3 and 5 of TB2 that should be Gnd, step and dir+
Connected the second stepper to pins 7, 9 and 11 of TB2, again Gnd, step and dir+

Drivers are both powered from the 24vdc supply and power lights are on

===========================================================================

Here's where everything starts going sideways for me

Run pncconf

Start

Select "Create New machine"

Forward

Call it "Lathe", leave default dir
Change to XZ Lathe
Inch

Select Mesa0 PCI/Parport card
None
Axis for the GUI

Forward

Position feedback - commanded (not sure why anymore)
Turn off "require homing before MDI/Running (mainly for this test at this time has no home switches)

Forward

Select 5i25 - internal data (have also tried 5i25 on it's own but makes no difference)
Select 7i76x2 With one 7i76 (have also tried selecting 7i76 on it's own that shows when I select 5i25 above)
change Num of step gen to 2 (x and z I figure but I've also left it at 5
Can't seem to change the PWM generator from 0 (how I don't need that)

leave everything else

Accept component changes

It creates I/O connector 2 and I/O connector 3 and 7i76 I/O (SS#0) tabs
Found a post that says that TB2 on the 7i76 isn't shown and that it's really wired through on the DB25 so I need to use I/O 2 and 3 to set the steppers up

I can't for the life of me figure out how these work

On I/O 3 it shows 0 and 1 where I can select X axis stepgen and z axis stepgen so I do

X-Axis StepGen DirGen-B (all grey out)
0 X-Axis StepGen StepGen-A (the one I selected)
Z-Axis StepGen DirGen-B (all grey out)
1 Z-Axis StepGen StepGen-A (the one I selected)

Here I can't seem to find any relationship between these two settings and the pins on TB2 of the 7i76

In the manual it says
Gnd, Step0-, Step0+,Dir0-,Dir0+, +5VP for pins 1-6
then
Gnd, Step1-, Step1+,Dir1-,Dir1+, +5VP for pins 7-12
Are those the 0 and 1 shown on the pncconf page?


then it has 004, 005, 006 etc as unused Inputs GPIO Input

0: 7i76 Mode 0 I/O card

I/O 2 goes from 017 through to 033 as unused inputs

7i76 Tab goes from 00 thru to 15 and then again from 00 to 07, so 24 inputs on TB6
16 through to 31 and then 08 thru 16 on TB5
TB4 is two analog outputs

The launch test panel button doesn't seem to do anything

Forward

I've just picked a pretty random stepper scale for now, 50 fir both the x and z

Save and save

When I launch the linuxcnc and select the lathe I just created, turn off the e-stop and "toggle" the machine power I'm getting no response from the steppers at all

Anyway, supper confused and frustrated, maybe I started at the wrong place or missed something that I should have done before the pncconf or something. I've spend hours now reading manual and posts that start ot make sense and then suddenly end or lose me completely.

Anyways, as can be seen, I could really use some BASIC level help in BASIC level terms for an old guy with zero Linux / linuxcnc experience

Thanks in advance
M

I hooked my 201vs to 5+ step- and dir- on my 7i96 because on the parallel port they ran pretty good with the step pin inverted

I used the 7i96 tool but also made one in pnconf. I think I remember seeing some of the step ins grayed out. I did select the 201 preset for timing.

I would not select any inputs for homing if your bench testing the motors and drivers.

On my paraport I got no movement also before I inverted the step pin with the 201 preset timing values

In the manual it says
Gnd, Step0-, Step0+,Dir0-,Dir0+, +5VP for pins 1-6
then
Gnd, Step1-, Step1+,Dir1-,Dir1+, +5VP for pins 7-12
Are those the 0 and 1 shown on the pncconf page?

Yes, pncconfs stepgen 0..5 are the 7I76s stepgens 0..5 (with standard firmware)

Thanks for confirming that

When I select the card, am I picking the correct combination even though I only have a single 7i76?

5i25 - internal data
7i76x2 With one 7i76

I also have the option of selecting
5i25
7i76x1

But they showed up after a lot of downloading various zip files

I believe I flashed the 5i25 with the x2 bit file last

Thanks
M

The first option is fine

OK, then it looks like I may have set up the basics of basics correctly, now to find out why there is no reaction at the steppers.
I'll have to put a scope on the step/dir pins to see if anything is happening signal wise
M

By far the most common reason I see for no response to step signals is that the
steptime is set too short ( 5000 ns is a good starting point)

Played around more tonight, still can't get any motion from the steppers
Tried setting the steptime to 5000, nothing
Tried using the built in Gecko 201 settings (apparently that's what these drives were copied off of) which uses a step time of 500, nothing.

I set one of the pins on the 7i76 as a limit and another as the e-stop, both of those seem to work properly so it's definitely talking to the card.

I need to find another way of testing the drives and the steppers to make sure they do work (worked when put away....)
Thanks again for the help

Do those drives have the current resistor or the dip switches?

Resistor, both motors are rated at around 6 and i've set the resistance for close to that but under.
I do hear one "twitch" when power is turned on.
I've got an old 3 axis xlotex driver board here and matching steppers from a desktop engraving mill, maybe i'll have to dig up those
~
M