On Tuesday 04 March 2014 16:11:06 Stuart Stevenson did opine: > > That is the situation we are discussing - sets of more than one > > variable (or HAL signal) that need to be transferred together. > > My take on this. > If I calculate more than one variable and those variables need to have > the calculated relationship when they are read I need to control the > write and the read to make sure the variable relationship is > maintained. > How the control is accomplished is not important. > > thanks for the information and links > the links get deep but I learned a lot from them > Stuart
One of the things I do Stuart, is to make sure that something in the halfile that is generating data, is in front of anyplace that data might go, in terms of that functions position in the addf order. That will not guarantee it will all be done in between any one base_thread instance, but it does guarantee that the generate/use is in the proper order. That helps to avoid stale data that has to wait till the next servo or trajectory thread instance, and makes the creation of an inadvertant lag pole n a feedback loop fairly unlikely. Invert that order several times, and the PID for the spindle becomes un-tunable. BTDT in the earliest days of setting up my spindle controller. I don't believe we have a huge problem in that area as long as the module exec sequence is controlled by its position in the addf list. Cheers, Gene -- "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> NOTICE: Will pay 100 USD for an HP-4815A defective but complete probe assembly. ------------------------------------------------------------------------------ Subversion Kills Productivity. Get off Subversion & Make the Move to Perforce. With Perforce, you get hassle-free workflows. Merge that actually works. Faster operations. Version large binaries. Built-in WAN optimization and the freedom to use Git, Perforce or both. Make the move to Perforce. http://pubads.g.doubleclick.net/gampad/clk?id=122218951&iu=/4140/ostg.clktrk _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
