7I80 + 7I33 + spinx1

I'm setting up my new conversion controls. 2hp spindle has a Delta VFD-E, which works fine.
and a real 1000ppr differential signal encoder attached to the spindle.

Primary card is a 7I80 (ethernet) with 7I33 quad analog servo amp which controls brushed DC's.
The 7i33 takes the pwm, dir, and ne and converts them to +-10v and enable.
The spinx1 takes pwm, dir, ne and converts to 0-10v range, plus cw, ccw, and enable.

So for a 3 axes plus spindle system I figure there are several overall configurations.
1. 4 pwmgens and 4 encoders >> first 3 of each are axes, 4th of each is spindle
but the 7i33 consumes the all of the signals as it occupies P1 entirely on the 7i80.
with no obvious way to attach the spinx1 to the 7i33's 4th output.
2. 5 pwmgens and 4 encoders >> first 3 pwmgens are axes, first 3 encoders are axes,
4th pwmgen is un used (still attached via the 7i33), 4th encoder is spindle thru the 7i33
which conveniently has a ttl/differential jumper, 5th pwmgen is spindle going to the spinx1.
3. 5 pwmgens and 5 encoders >> first 3 pwmgens are axes, first 3 encoders are axes,
4th pwmgen and encoder are unused (on the 7i33),
5th pwmgen and encoder are spindle. pwmgen to the spinx1,
but the spindle encoder is differential and direct connect to the 7i80 (not thru 7i80) is ttl.

it's a quandary.....
for 1. is there a way to intercept the 4th set of pwm,dir, ne signal going into the 7i33 to connect to the spinx1 ???
for 2. a little odd, not having consecutive, consistent signal settings for the spindle , but it works....
for 3. how to use the spindle differential signal directly to the 7i80 ??? like A to pin and Anot to ground???

I sure could use a little help and advice on this one......
Thanks, way in advance......

I would probably use option #2

You really don't want to wire any differential encoder signals directly to a 7I80,
since encoder signals connected to servo motors and VFD driven induction motors will
have large amounts of common mode noise.
The 7I33s differential receivers can accept a +7/-7V common mode range in normal
operation and are not damaged by +-14V inputs. The 7I80 inputs can be damaged by al little as -0.7V

PCW.
thanks. that is actually what I have wired.
there are also 7i42's between the 7i80 P2 and the 50 pin breakout, and another between the 7i80 P3 and a 7i37..... cheap insurance.
Right now i'm working on the spindle control with PID. quite a challange.
any tips? specific to spindles....

how about a simple circuit based on an LM339, quad Comparator,
to convert the encoder differential signal to ttl ??
seems pretty simple. the IC and a couple of caps...?

oh, heck, you have that.............422ENC.................can't tell what ic it is in the photo............