#linuxcnc-devel Logs

Mar 20 2021

#linuxcnc-devel Calendar

05:09 PM mrec: so those hal plugins are just polling in a loop? is there no direct notification?
05:15 PM mrec: I'm looking at hy_gt_vfd.c
05:15 PM mrec: I have interfaced the potentiometer, and frequency counter of my chinese mill
05:16 PM mrec: well looking I think I should be done with the driver..
05:16 PM mrec: based on hy_gt_vfd.c
05:16 PM mrec: https://www.weissmachinery.com/bench-type-milling-machiune/57296012.html
05:20 PM rs[m]: mrec: i'm not sure what kind of notification you expect
05:21 PM rs[m]: mrec: modbus is a simple protocol
05:21 PM mrec: I removed modbus already
05:21 PM rs[m]: with a single "master"
05:22 PM mrec: so this hal is synchronising the data in a background thread or how does that work?
05:22 PM mrec: my interface is simple, SSN (spindle speed value), GCS (get current speed)
05:23 PM rs[m]: shared memory
05:23 PM mrec: ah
05:24 PM rs[m]: http://linuxcnc.org/docs/2.8/html/man/man3/hal_malloc.3hal.html
05:47 PM mrec: ok I have built the plugin
06:43 PM mrec: that was nice and easy
06:46 PM mrec: I can see the driver in the hal configuration and I'm able to adjust the spindle speed with setp
06:54 PM mrec: rs[m]: do you know a quick way to forward the spindle speed value to a driver?
07:16 PM mrec: ok I think I have it
07:20 PM mrec: is there a way to override the spindle speed command to not require homed axis?
07:22 PM mrec: ah TRAJ section
07:28 PM mrec: cool it works
07:28 PM mrec: M03 S110
08:57 PM mrec: I just cannot home the machine until I assemble it again :-)
09:37 PM andypugh: mrec: Yes, many userspace HAL modules just poll in a loop.
09:37 PM andypugh: Realtime modules run once when called by the realtime thread.
09:38 PM andypugh: it is possible to respond to signals in some cases: http://linuxcnc.org/docs/2.8/html/hal/halmodule.html#_use_with_hal_glib_in_qtvcp_handler
09:39 PM andypugh: But that really just means that something else is polling in a loop.
09:41 PM skunkworks: andypugh: I think gene just needs to buy a real harmonic drive.. (but then again - so should I)
09:41 PM andypugh: I think yours looks usable.
09:42 PM skunkworks: parts as they are not concentric.
09:42 PM skunkworks: wow that is missing a bunch
09:42 PM skunkworks: I think so too. I found out my probe on the K&T was slightly off.. I had to rework a few of the
09:42 PM skunkworks: parts as they are not concentric
09:42 PM skunkworks: but no real issues.
09:43 PM skunkworks: Should quiet it down a bit.
09:43 PM skunkworks: some things where .005" from center
09:44 PM andypugh: Anyway, time to sleep here.
09:45 PM skunkworks: Night