On Tuesday 01 September 2015 15:32:51 John Kasunich wrote: > On Tue, Sep 1, 2015, at 03:12 PM, Gene Heskett wrote: > > Sample_hold is s32 except bit "hold", and the man page doesn't even > > say what state is hold & what state is fall-thru. > > > > comp is float, incompatible with the S_H > > > > Sum2 is float, incompatible with the S_H > > > > So the processing chain is too long and likely in the wrong addf > > sequence. But it would be a huge help if we had a float version of > > the sample_hold. > > > > Any chance of that ever happening? > > It's already there, it just isn't called sample-hold. > > Mux2 can be used as a sample-and-hold. Tie "in1" to the output. > "in0" is the input. When select is 0, "in0" is copied to the output. > When select goes to 1, the previous output enters thru "in1" and is > copied to the output. Presto, it holds.
Nice, but I had to interchange the input assigmnents because the equals goes true. This works and I can see the individual steps propagating thru the 4 step chain at low speeds, with about 1/4 the noise in the final sum2's output. As the spindle speed rises there is a place where its never true, so it just falls thru in the reverse of the addf sequence. But I am still trying to sort the feedback and the pid for a good stiff control. Some of that is a huge loss in the gearchange module that pncconf installed because its a 2 speed head, and some of the speed error is there because the actual input to the 5i25's pwmgen.value is only about .45xx at 1000 rpms delivered. Setting FF0 down to .87 gets a lot closer to 1k revs when you've type s1000 though. so I changed that in the ini file. FF1 seems ineffective up to 10 or better, Pgain is 2500, Igain is currently .075 and that seemed to soften the m3-m4-m3 turnarounds a wee bit. But even with Pgain at 2500, the speed if I grab the spindle, is regulated what I'd call poorly. The toy mill, with no encoder on its spindle is much stiffer, so stiff that I had to put an ammeter in to see the motor current, as there is no detectable change in its spindle speed as the load goes up until it has cleared the motors fuse! 15 bucks for the ammeter has probably saved me a hundred bucks worth of fus es over the last decade since I put the meter on it. I can slow this spindle 15% just by wrapping a few fingers around it, without burning up my fingers from the friction. Got a honeydo, later. Thanks John. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Monitor Your Dynamic Infrastructure at Any Scale With Datadog! Get real-time metrics from all of your servers, apps and tools in one place. SourceForge users - Click here to start your Free Trial of Datadog now! http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
