Spindle encoder feedback

Hello, today I spent a few days trying to do the spindle encoder feedback, I was looking at other posts right here on the forum until similar problems but not the same and old too.  I'm making a lathe, using Gmoccapy, a 7i76E board connected 1000ppr encoder (E6B2-CWZ6C) to the motor.  The encoder works from 5-24vdc, NPN, A, B and Z signals. I did the pin signals tests there at Halshow and they are arriving perfectly from the board.  I do the rotation test with or without the encoder it doesn't make any difference (I feel like I can't read) I physically turned off the encoder it obeys the frequency inverter rotation, as before.  It has a small rpm range but it does.  My question how do I effectively test closed loop?  Is there any way to view it on the screen too?

If I remember correctly you needed the spindle encoder to get synchronized motion (ie rigid tapping) to work. For that you don't need to close the loop with all the pid tuning you just need the direction and velocity feedback from the encoder.
Maybe you could post your current ini and hal.

no, my main objective is precisely for precision, tolerance to make rigid tapping

Note that spindle synchronized motion (ie. rigid tapping) does _not_ require precise spindle rpm. The idea is that the _actual_ spindle rpm is fed back by the spindle encoder and that is what drives the linear (ie. Z) motion.
So in the spindle slows down the z-feed slows down, if the spindle comes to a standstill the z-feed stops and reverses once the spindle reverses to extract the tapping tool.
But if you feel you need to have the pid in the loop you can certainly do that even if it's unnecessary.

As others have explained, closing the spindle velocity loop is not needed
for threading and rigid tapping because the Z axis motion is effectively
geared to the spindle position. If you want to try closing the loop and you
created your original configuration with pncconf, you can add some
P term to the spindle PID.

In my mind to do this work there was a need to use closed loop.  So you mean you don't even have a need to use an encoder?  My spindle motor for example I'm measuring with the tachometer directly on the motor and it measures 10 to 15 rpm less than the nominal placed in the system and a variation of more or less 5 rpm for positive and negative.  Can I work quietly like this then (excuse my ignorance)?

You need the encoder. This is what allows LinuxCNC to "gear" the Z motion
to the spindle rotation. You do not need close loop speed control as the Z axis motion
is locked to spindle position (read from the encoder) when doing spindle synchrronized motion.

+-10% or so speed variations should not cause any issues at all.

Ah ok, understood PWC, tks.

I was looking at Halshow right now my encoder is coming from 7i76E the signal plus there in PID >S>feedback the value is at 0, it must be something in my Hal file I'll give a study about it.

Today I was finally able to read my encoder feedback signal.  Before, I could only see the signal from the Mesa board through Halshow, now I can see it through the PID.S (as attached).  Could someone confirm me if the scale (resolution) is right?  I'm thinking it's wrong, my encoder is 1000 ppr and in the ini file I also put 1000, the spindle rotation turned on 1000 rpm, but the motor rotates at 2000 rpm because it has a 1:2 reduction.  Is this feedback value correct?  Another thing also the sign Z (index) is not informing either, by the board Mesa arrives more appears, this one I couldn't understand.  Is this signal needed to make thread synchronization?  Thanks for the help thanks to you things are evolving.