[PMDX-126] Slaved Axis question

[Pierantoine]

Hello,
i would like to use a PMDX-126, i'll use two ballscrews with one stepper on each one for my X axis, i'will use am882 leadshine drivers.
i've RTFMized this :-)  (but maybe i miss something?) ..and discover that i'could use the jumbo mode to get more axis. i've seen that an axis could be cloned but is direction is inverted...

is it possible to slave, clone an axis without an inversion in hardware, ? (my two steppers should turns identically).
or can i wire the same step and dir of an axis to two drivers? (inserting resistors if needed)
or do i have to slave the axis in the software Mach3 / EMC

Thanks for your help.

[Bob at PMDX]

I apologize for taking so long to reply, I've been out sick for a few days.

You can use "jumbo" mode on the PMDX-126 even if you want both X axis motors to turn in the same direction.  All you need to change the wiring between the motor driver and the motor.  For the motor that is on the "cloned" outputs from the PMDX-126 (connected to PMDx-126 J5 pins 4 and 5), take the two wires for one phase of the motor and swap terminals on the motor driver.  This will cause the motor to run the opposite direction.

First, make sure that the two X axis motors turn the same direction when fed the same "DIR" signal.  Then, swap the wires for phase B (or phase A, either one, but not both).  Take the motor wire from the "B+" terminal on the am882 and connect it to the "B-" terminal.  And take the wire that was connected to the "B-" terminal and connect it to the "B+" terminal.

Another method is to connect both motor drivers to the same pair of step/dir pins on the PMDX-126.  However, you cannot do this with the Leadshine am882 drivers.  The PMDX-126's outputs do not have enough current capacity to drive two of the am882 inputs.  The PMDX-126 outputs can handle up to 16mA on each output.  The am882 requires a maximum of 16mA per input.

Bob

[Pierantoine]

Thanks !  very clear !