trying to get rotary axis working

[lab auto man]

Hello,
I have a PMDX-126 run by USB SS and I am trying to get a rotary axis working.  The axis is driven by ClearPath SD servo.  I have  step wire going to pin "16" on J6 and the direction going to pin "17" on J6.  The enable is connected to +5 PC and all commons are connected to ground PC.   This rotary axis uses the B motor in Mach 3 and is parallel to my Y axis.  I believe I have all the settings in Mach correct.  If i try to use MPG to move the rotary axis The numbers on the screen change  but no real movement. The servo drive is in servo lock.  I do not see the LEDs at pin 16 or 17 light or change at all.  I do not believe I am getting step or direction signal from the PMDX-126.  All my other axis work x,y,z and C slaved to X.  Any ideas?  what am I do wrong?
Thanks,
Todd

[Steve Stallings]

If you are able to get other axes driven by a ClearPath SD servo to run
properly, then we can assume you have the Enable wired correctly and
your drivers configured correctly.

If the LEDs beside the "16" and "17" legends on J6 of the PMDX-126 do
not respond to Mach commands, then a configuration issue likely exists.
It is easy to see the Direction signal because it always remains in the
last used state. The Step signal may be too faint to see because it is
too fast.

You might pins 16 and 17 double mapped. If more than one Mach signal
is trying to drive these pins the results are indeterminate, and unlikey
to run a motor.