Z axis is being controlled by A

I've got a new install on an RPi4 with a 7i92TF and an MX3660.  The DB25 is on a ribbon cable with a third cable end pressed onto it.  I have A step/dir on pins 8/9.  The MX3660 does also use 8/9 but only to drive isolated outputs that aren't connected to anything.

IIRC I used the Geckodrive G540 flash on the 7i92.  The readhmid is enclosed.  DB25 8/9 should be stepgen 03.

I don't have homing set up yet.  XY jog fine.

Initially, I saw XYZ axes moved ok but then I tried to jog A and both A and Z moved.  That's as best I recall, it was late last night.

I looked at what I had in the hal and, ok, the joint and stepgens for A were off like that.  IIRC what I saw had A on stepgen 2.

I did the logical thing and X=Joint 0 stepgen 0, Y=Joint 1 stepgen 1, Z=Joint 2 stepgen 2, A= Joint 3 stepgen 3.  Order XYZA.  HAL/ini enclosed.
At least that's what I tried to do.  The machine thinks differently, I keep looking for the prob in the hal/ini but I don't see where the typo is.

The problem is, any attempt to jog to Z (keyboard, MDI) won't physically move anything, although the Z in AXIS does increment.  
But, if I select the radio button for A axis, or use the MDI on A axis, it moves both the A and Z.

I unplugged the A-axis DB25 tap.  Z commands won't move the Z, A commands do still move the Z, but of course A is disconnected so it won't move.

What am I missing here?