Introduction to this forum

[JuKu]

I've heard that LitePlacer hardware can run OpenPnP software (http://liteplacer.com/phpBB/viewtopic.php?f=13&t=308), and in a private discussion, Jason said that it should be possible to use unmodified hardware with a proper configuration file. I suppose that this means more users selecting or at least testing that option, too. I created this forum to hold these discussions.

[vonnieda]

Thank you JuKu!

I'm Jason von Nieda, from OpenPnP. I've been monitoring Pixopax's OpenPnP thread and helping where I can. In the near future I will be working to make sure that OpenPnP works well with the LitePlacer hardware and will, once we have the problems sorted out, be posting a Wiki page with instructions on how to use the software. I'll post back here when that is ready. In the meantime, if you have ideas, questions, thoughts, suggestions, etc. for OpenPnP on LitePlacer, please let me know!

Jason

[gtrplaya101]

I am so excited for this! Let me know if there is anything I can do to help. I would love to be able to use OpenPnP with my liteplacer

[michael-yurov]

In LitePlacer axis Z upside down. It is not comfortable.
If you want to use OpenPNP, you must change the Z motor winding.

Also in LitePlacer has swapped axis Z sensors.
To use the Open PNP sensors should be swapped.

Also you need to change the Z-axis sensors settings in the TinyG board settings.

I think it would be wrong if Jason will change OpenPNP for compatibility. Because all machines Z axis must look up, not down!

[vonnieda]

It should be possible to invert the Z axis just by changing the configuration in TinyG.

https://github.com/synthetos/TinyG/wiki ... --polarity

If this work, we can just send this command from OpenPnP during connect to make sure it's always set right.

[michael-yurov]

Jason, I tried to change the Z Axis polarity (with inverted motor connection as it is necessary for the LitePlacer).
In this case, the Z axis moves in the right direction and coordinates increase when moving up, and decreases when moving down, as it should be.

But I still was not able to configure the sensors to the machine properly search home, because sensors are connected vice versa / swapped.
The upper sensor is connected to the Z_Min input,
and the lower to Z_Max input.

If I configure Z_min (top) sensor as a home sensor, then Z axis moves down to search home.
If I configure Z_max (bottom) sensor as a home, then Z axis moves up to search home, but it does not stop when the upper (Z_min) sensor is triggered.
If I configure both sensors as a home, the machine is not moving and is not trying to find the home.

(I'm sorry, I have poorly writing in English)

[vonnieda]

Jason, I tried to change the polarity.
In this case, the Z axis moves in the right direction and coordinates increase when moving up, and decreases when moving down, as it should be.

But I still was not able to configure the sensors to the machine properly search home, because sensors are connected vice versa / swapped.
The upper sensor is connected to the Z_Min input,
and the lower to Z_Max input.

If I configure Z_min (top) sensor as a home sensor, then Z axis moves down to search home.
If I configure Z_max (bottom) sensor as a home, then Z axis moves up to search home, but it does not stop when the upper (Z_min) sensor is triggered.
If I configure both sensors as a home, the machine is not moving and is not trying to find the home.

(I'm sorry, I have poorly writing in English)

Ah, I see. That might be tricky then. I wonder if we could set polarity to 0 before homing and then set it to 1 after homing?

[michael-yurov]

Ah, I see. That might be tricky then. I wonder if we could set polarity to 0 before homing and then set it to 1 after homing?

I thought about this, too.
That should work!
(if there are no confusion with the coordinates)

But this is a bad way...

It would be better if Juha change the settings for LitePlacer.
I understand that this will create problems for many users, and the need to correct the documentation, but it would be correct.

Coordinate Z should be look / facing upward. Always. On all machines.
Just like the gas pedal must be right, and the brake pedal in the middle.

[michael-yurov]

Oh, also... I think that the use of LitePlacer and OpenPNP at the same time is not a good idea.

[vonnieda]

Oh, also... I think that the use of LitePlacer and OpenPNP at the same time is not a good idea.

If you mean running both LitePlacer software and OpenPnP software at the same time - yes, you are correct. They should never be run at the same time since each assumes exclusive control of the machine.