spindle control of PM-728vt using linuxcnc

First test PM pin1 (FW) connected to PM pin 3(COM)
     - command m3 s400  Spindle turns CW at 400rpm
     - command m4 s400  Spindle turns CW at 400rpm    Why
Second test PM pin2 (REV) connected to PM pin3(COM)
     - command m4 s400 spindle turns CCW at 400rpm
     - command m3 s400 spindle turns CCW at 400rpm     Why?

Why does connecting eaither FW or REV seperatly  allow the same rotation when issuing both m3 and m4 to each.  This cant be right.

thank you
jim


 

Its not right

You need to assert FWD or  REV to the PM interface independently
Your current wiring does not allow this

You also need to get the polarity of FWD and REV correct

The required polarity and function of the FWD/REV inputs 
should be determined  before running LinuxCNC

Test 1 was run with only FW signal connected .
Test2 was run win only REV signal connected.

jim

FWD or REV connected to COM with a wire?

Yes, that's correct.

Thanks
jim

OK, that's the expected behavior for active low FWD and REV

(because LinuxCNC is not in control of direction of your hardware, your hardwiring is)

My OUT7/OUT8 or Relay suggestions in a previous post should work