Jon, I did mean us, not ms. I sent another message to try and clear the muddy waters on that one.
So what is the jitter limit at which the realtime error is thrown? Is this something that can be changed in the configuration somewhere? I have been under the impression that 25us is acceptable for stepping as long as you can generate the speed you need within the acceptable limits. Many have claimed that you need very low jitter values and others have claimed that it is not as critical as some make it seem. I did notice that nothing was changing in the halfile when I would change the jitter value in stepconf. I was curious if this was changing anything except the theoretical maximum pulse rate and therefore the theoretical maximum velocity. Thanks, Jim On 5/6/2016 11:06 AM, Jon Elson wrote: > On 05/06/2016 09:12 AM, Jim Craig wrote: >> I have set up my router with my new computer. This computer runs at >> about 25ms jitter on the base thread for hours with 2 glxgears running, >> moving windows, copying files etc. > I hope that is 25 us, not ms. 25 us is not great, as it > causes a 2.5% fluctuation in the sampling period. >> This system runs off a parport, and I set initially set it up in >> stepconf wizard to have a 30ms jitter value. >> >> When I run LinuxCNC I get a realtime error a few minutes after I start >> the program. > The realtime error message tells the magnitude of the error, > that is important. If it doesn't exceed your 25 us jitter, > that is not a disaster. But, the realtime error message > only fires once per run of LinuxCNC, and so you are then > blind to any more serious errors that happen later. Not a > great situation. >> I am using 2.7.4. This is repeatable and happens each and >> every time I run LinuxCNC. > Yes, you will only get the message once. That does NOT mean > that the error in not happening again! >> I reran stepconf and changed the jitter value to 50ms to see if that >> would fix it and it did not change anything. >> >> > Stepconf has NOTHING to do with anything except software > stepping, so it certainly will not "fix" this problem. > What you did will generate a more conservative software > stepping configs file set. > > Jon > > ------------------------------------------------------------------------------ > 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
