I've got CNC10 LInux with a DC3IO. The XYZ axes are fine.

I'm in the process of hooking up a 4th axis with the DC Single add-on drive after having the 4th axis stuff "resting" for a long time. I have a new F14 Dynapar encoder on the servo motor.

I did the wiring in the cabinet today after finishing the cable and started checking things with the motor clamped to the mill table (not to the rotab yet). I'm getting a 410 axis position error.

I've changed the motor spin direction in the config area, and that makes no difference. The motor always turns in the same direction no matter which direction I turn the MPG dial or if the direction is reversed or not in the config page. The count in PID keeps decreasing, always showing a negative number that gets ever smaller (more digits in the number, so think of it as a negative increase).

As best I can tell I've got the encoder cable/plugs/DB9 wired correctly, but I suspect I'm not getting a signal from the A or B channel or maybe have something miswired (probably the latter). I get counts, it just can't seem to tell anything about what direction it is going in.

So since I am getting counts, does that mean that either the A or the B channel is fine and I messed the wiring on the other pair? My limited understanding is that direction is told from the A leading or following the B.

How do I troubleshoot this? Should I take an DCV reading between the A and A/ and then the B and B/ wires to make sure I got them in the right position. Is the Z and Z/ the index signal, which sounds like it should be showing up once per rev as a voltage change?

I am not an electronics person and I don't have an O-scope. But I've done 2 Centroid mill conversions and they've both worked so I suspect I've got an "oops" buried in the DB9 cable to the PC/motion control board. I'm hoping at worst I can change locations and resolder on a couple of wires in the AMP connector from the conduit to the rotab, and not need to rip everything apart to pull the encoder cable out of the conduit.

The home/clamp ack signals are fine and show up in the ALT-I screen, the motor spins, so it seems like it would have to be an encoder issue. But that's just my non-electrician guess.

thanks,
Michael