z-axis home

[skrap]

I've tried version 1.2029, 1.2031, 1.2036 and see the same behavior.

I have the z+ limit and z home set to the same input pin (no z- limit sensor). They are both set to active low. It functions properly in the diagnostics tab. The softlimits are 0 for limit- and 8 for limit+, with a value of 8 for 'write offset on homing'.

When I check the box for 'positive direction' the z-axis drives toward 0 when homing. If the box is unchecked the axis drives in a positive direction. It seems to me that behavior is backwards.

Also, when the home switch is triggered the axis doesn't stop (doesn't matter which direction the axis is traveling or if the 'direction positive' box is checked). I don't think motion is stopped when the limit switch is tripped when not homing either.

Let me know if there is anything you want me to try.

[cncdrive]

You likely have the home input pin polarity (low active) setup in reverse, so when you start the homing the controller thinks that your axis is already on the home switch,
so it starts with the downwards movement, the upwards movement does not occur at all in this case.
This is why your axis behaves the opposite way as you set the home direction, it behaves fine, but because the polarity is reversed you only see the downwards which is the opposite direction movement.

Verify if the Home pin LED should be off when the axis is off the switch, if the LED is on when the axis is off the switch then you have it configured in reverse.

[skrap]

If the box for 'dir active low' is checked or not the behavior is the same - the DRO goes positive if 'direction positive' is unchecked and vice versa.

The home switch is configured correctly. The LED is off when the switch is not activated.

Any other ideas?

[cncdrive]

Please post your profile file to let me check and test with it.

[skrap]

Thank you for looking into, everything seems to be set up correctly. I have tried many different configurations with no luck.

I've attached my profile.

[cncdrive]

We've managed to debug the problem you reported and really there is an issue, the exact problem is with Port#4 Pin#6 which you have the Z-axis home pin configured to.
This exact pin definition is wrong in the API and that is why the home is not working properly on this pin.
The issue was corrected now and will be OK in the next release, but for now what you can do is to rewire the home input of your Z-axis to any other pins and/or any other ports.

[skrap]

I can't change the pin assignments on my break out board since it has a LPT header (not screw terminals). Can I move that LPT cable to PORT1 or PORT5 of the UC300ETH (PIN6 will still be z+ home)?

[cncdrive]

Yes, that is what I adviced as one possibility.

[skrap]

Great! Thank you for looking into the issue and solving it.

Is it the test release forum post the best way to know when a new test release is out?

[skrap]

I switched the cable and all the settings from PORT4 -> PORT5. It is working correctly now, thank you.