Last year I retrofitted my laser engraver with linuxcnc. I do both rastering and vector cutting on my laser, and it is a 4 axis laser as I do complicated raster and vector cutting on 3D objects.
I found existing solutions out on the web but they weren't quite adequate for my needs. Because I have a 4 axis laser (XYZA), controlling vector power using the Z axis was out. Also my raster files are sometimes 200Mb and streaming raster data at the servo period rate via gstreamer takes quite a long time. I also did not want to have a separate raster data file alongside the gcode file. To solve these and some other problems I needed a way to pipe data through the HAL at a rate much greater than what could be achieved with 1 data point per servo cycle. Thus the HAL_PORT pin type was born. The idea was taken from machine kit ring buffers. A HAL_PORT pin allows for a writer component to send many bytes in one operation to a reader component in real time. The PORT pins behave just like any other pin in HAL and can be linked, unlinked etc... In addition to the modifications to make hal ports some other modifications and new parts were required. halcompile.g - added port type. Also added (pin,param,variable)_ptr macros to allow access to the actual pointer to those values. pyhal.py - similar to the other python component pyhal.py uses the ctypes python library to interface with hal, which is significantly less code than the halmodule.cc python wrapper that currently exists. laserpower.comp - allows vector control of a laser, scaling power during a move and has no limitations of number of joints a machine can have. raster.comp along with a python raster.py programming module to control the raster, this allows control of the raster component from user space. remapping of M codes to control the raster.py raster programming component. Included is also some tests /tests/pyhal - also tests hal_port implementation /tests/raster - tests the rastering component and raster.py programming interface Included is also a sim config detailing how to implement a laser engraver with vector and raster support. In /configs/sim/axes/laser I have been using this in production for a few months now. I am open to any and all suggesstions on how to structure, features, functions, etc. I also think that the HAL_PORT can be used as a primitive to build or replace a lot of code. Maybe even NML and other forms of shared memory magic. Eventually I would like to get this merged into master. I'm open to doing this in an incremental type fashion so as not to disturb too much at one time. This is my first "PULL request" with linuxcnc so forgive my ignorance with regards to this process. Link to commit, merged with latest master https://github.com/OKComputers/linuxcnc/commit/0afff760caa3f96d47d9934dc4d07765d40f2591 Thanks, Curtis ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
