On Monday 27 February 2017 09:01:47 andy pugh wrote: > On 27 February 2017 at 13:49, Gene Heskett <ghesk...@shentel.net> wrote: > > What I wanted was a binary counter, whose individual bitN outputs > > could drive the selN lines of a mux16, thereby selecting the gain to > > be applied to the jogwheel output. > > Mux-generic can be driven by an integer (and, possibly usefully for > you, you can also use the bit-inputs to "shift" the selection.) > http://linuxcnc.org/docs/2.7/html/man/man9/mux_generic.9.html > > http://linuxcnc.org/docs/2.7/html/man/man9/updown.9.html > Looks like the solution to the counting up and down part. > > One slight inconvenience is that updown is S32 out and mux_generic is > U32 in.
Which the s32 says updown can count negative values, which is good. That means I can design for all speeds in both directions. Humm, and what does it do when the input is an s32 representing a negative? Say of a -3 or a -14 (no floats allowed)? I'll start with the updown and see if I can make the min/max behave as desired. I had rejected it originally because of the logic needed to determine the direction, derived by a wcomp from the encoders velocity output, and applied to a not and 2 and2's to derive the step up for that pin, or the step down for the other. How wide, in terms of inputs, can I make a single instance of this mux_generic? Sounds interesting but a bit of a bear to properly setup with all those options. 16 is likely overkill with a 1,2,5 sequence to the gain. In practice, 6 or 7 would be sufficient I think, if not overkill. 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> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
