Two toolheads in the Z axis with different step and dir pins

[koneklaudio]

Hi,
I have a machine with two parallel toolheads in the z axis, each one with an independent stepper motor.

Today, I have one of them assigned to the A axis in order to be able to control them separately. But it's not very practical.

What would be the best approach to have both assigned to the z axis, and be able to switch from one to the other (with an M6 command)? The controller should change the step and dir pins. The x, y and z location should be independent for each tool.

[terjeio]

A relay to switch step/dir signals combined with a custom plugin trapping tool change commands?
The offset plugin could be used as a template since it handles XY offset? Change it to trap tool changes instead of spindle changes.

[koneklaudio]

Hi thanks for the answer. I will have a look on that plugin.
Using a physical relay is not an option, since I am reusing a motherboard which cannot be modified (It would require microsoldering).

[terjeio]

Using a physical relay is not an option, since I am reusing a motherboard which cannot be modified (It would require microsoldering).

Then you have two options, either modify the core or trap the step output calls in a plugin to the driver and swap Z step/dir signals to A when called for. The latter is, IMO, the best option.