What I ran into was that the G540 lists a 3.3v compatibility, and a 1 us high/2us low pulse time.
But those pulse times won't work for 3.3v. The G540 requires MUCH longer pulses, however there's a lot of room. If you were running a stepper at 1200 RPM (pretty high), that's 40KHz steps, a 12.5us on-period would make a 50/50 duty. Try: DIRSETUP = 6000 DIRHOLD = 6000 STEPLEN = 8000 STEPSPACE = 8000 If you try to step a G540 too fast, weird things happen. I had mine actually freewheel, even though it was enabled. Danny On 4/20/2016 9:15 PM, fritz wrote: > In the process of upgrading every computer I have, I've come up > against some problems with my cnc install. > > I have tried 4 different linuxcnc installs; 2.6.12 at an intermediate > stage, and 3 different 2.7.4 installs. I've even tried building from > source, so technically I've done more than just 4. > > First, a i386 Debian Jessie install: > - from buildbot: 2.7.4-uspace > - from Jessie backports: 4.4 rt_preempt kernel > > Second, a amd64 Debian Jessie install: > - from buildbot: 2.7.4-uspace > - from Jessie backports: 4.4 rt_preempt kernel > > Third, an install using the current Debian Wheezy iso from > linuxcnc.org, apt-updated to linuxcnc 2.7.4 > > My hardware: > - AMD E350 dual-core with integrated graphics > - Mesa hostmot2 6i25 + 7i76 > > The mill: > - Taig cnc micromill > - Huang(?) VFD and spindle > - Gecko 540 stepper driver > > I went about upgrading and ended up on linuxcnc 2.6.12. I 'rebuilt' > my config using pncconf. This had a strange result of that while the > stepper and digital I/O were working, the 7i76 spindle output no > longer worked. I even tried doing a new config with pncconf, with the > same result. > > I saw that linuxcnc 2.7 was stable, so I did an install on a separate > drive for that. I installed linuxcnc 2.7.4 for uspace. I carried over > my conf file, and rebuilt the config using pncconf again. > > Now, the VFD output works, the digital I/O works, but any axis > movement results in a following error. > > There *is* stepgen output, because I have one stepgen output as the > charge pump to the Gecko 540, and it clearly indicates when it is > enabled. > > What is really funny is that even if I increase the following error by > orders of magnitude, this merely delays the following error, and > produces no stepper motion at all. > > How does linuxcnc make a following error with open-loop steppers? > How would linuxcnc be able to setup the charge pump stepgen, but not > my XYZA axis? > > Attached is my config files, and one session of verbose debug output. > > My next move is to go back to some earlier linuxcnc version, but I'm > not sure which one, yet. > > > > > ------------------------------------------------------------------------------ > Find and fix application performance issues faster with Applications Manager > Applications Manager provides deep performance insights into multiple tiers of > your business applications. It resolves application problems quickly and > reduces your MTTR. Get your free trial! > https://ad.doubleclick.net/ddm/clk/302982198;130105516;z > > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
