[Emc-users] converting parport to 5i20 config - joint following error
I started converting my EMC2 mill from parport to the Mesa 5i20 hostmot2 stepper and got stuck with a problem. The parport configuration works fine but the hm2_stepper config is having problems. I keep getting joint xxx following errors. I checked the docs but cannot explain this: ferror, min_ferror, max_velocity and mac_acceleration are the same in both cases and - although not necessary - I added the base_period to the hostmot2 configs. A second problem (maybe related ?) is seen during a manual jog. When an axis stops it keeps humming and the digital readout flips between the current position (e.g 2.001) and adjacent positions (e.g. 2.002). This was all done on 2.3.0~beta2 with the hm2_stepper config files from that release. Any ideas? All config files are available at http://www.myvoice.nl/freesmachine/configs/ Regards, Rob -- This SF.net email is sponsored by: High Quality Requirements in a Collaborative Environment. Download a free trial of Rational Requirements Composer Now! http://p.sf.net/sfu/www-ibm-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] converting parport to 5i20 config - joint following error
Rob Jansen wrote: I started converting my EMC2 mill from parport to the Mesa 5i20 hostmot2 stepper and got stuck with a problem. Another brave hm2 testing volunteer! Welcome! I keep getting joint xxx following errors. I checked the docs but cannot explain this: ferror, min_ferror, max_velocity and mac_acceleration are the same in both cases and - although not necessary One problem with the configs you linked below is that [TRAJ]MAX_LINEAR_VELOCITY is greater than [AXIS_?]MAX_VELOCITY. That means the hm2 stepgen will fall behind where the trajectory planner wants it to be, leading to following errors if it gets too bad. There's also no [TRAJ] acceleration limits, i'm not sure what it will do in that case. Oops, i see that the hm2 sample configs has the vel and accel settings sort of messed up, i'll fix that for the release. - I added the base_period to the hostmot2 configs. This config has no base thread, so it needs no base period (but it won't hurt to have one). With Hostmot2, the base thread is running in the FPGA. A second problem (maybe related ?) is seen during a manual jog. When an axis stops it keeps humming and the digital readout flips between the current position (e.g 2.001) and adjacent positions (e.g. 2.002). This was all done on 2.3.0~beta2 with the hm2_stepper config files from that release. The humming and dithering across the setpoint is a known bug in 2.3.0~beta2, it's been fixed in CVS and will be in the next release. -- Sebastian Kuzminsky We need numbers, not adjectives. -- David MacKay http://www.withouthotair.com/ -- This SF.net email is sponsored by: High Quality Requirements in a Collaborative Environment. Download a free trial of Rational Requirements Composer Now! http://p.sf.net/sfu/www-ibm-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] converting parport to 5i20 config - joint following error
Sebastian, Another brave hm2 testing volunteer! Welcome! Yep, slow system, problems with parport and not enough I/O made me buy two 5i20 cards (and a 7i43) card. One 5i20 for the main system, one as a backup/second system at home and the 7i43 to play around with and try some FPGA programming. I set up a 'new' system with EMC2 (Ubuntu 8.0.4 LTS release) from the live CD, updated this to 2.3.0~beta2 and started to play around with it. Both with my existing parport and with the new hm2 config. In my situation (milling a curved surface with a radius around 30 cm in all 1mm long line pieces) the hm2 config is 10% faster than the parport one. One problem with the configs you linked below is that [TRAJ]MAX_LINEAR_VELOCITY is greater than [AXIS_?]MAX_VELOCITY. That means the hm2 stepgen will fall behind where the trajectory planner wants it to be, leading to following errors if it gets too bad. This did the trick. I changed/added the [TRAJ] parameters and now even tort.ngc works almost perfectly! Almost ... the first time I start EMC it still gives a joint following error on axis 0 but if I quit and restart it's OK. There is still a lot to do in cleaning up the configs and making sure that all my other I/O gets in there but this is a promising start. The humming and dithering across the setpoint is a known bug in 2.3.0~beta2, it's been fixed in CVS and will be in the next release. I could not resist; 30 to 45 minutes of downloading and compiling and I have the trunk running. Humming and dithering is fixed. Still works almost perfect. One very small thing is that the splash screen reports 2.4.0~pre and the title bar of axis 2.3.0~beta1 but I think I can live with that ;-) Thanks, Rob -- This SF.net email is sponsored by: High Quality Requirements in a Collaborative Environment. Download a free trial of Rational Requirements Composer Now! http://p.sf.net/sfu/www-ibm-com ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
