How about a capacitor based delay circuit? AND-gate it with your one shot pin.
When power is off, capacitor bleeds empty through a resistor to ground. On power up, the delay circuit is held low until the cap is charged. It stays charged until power is shut off again. Set the "output enable" threshold with a zener diode perhaps (if the AND gate doesn't give an on voltage you like) and the delay with capacitance size. Best, Jason On Dec 2, 2012 2:31 PM, "N. Christopher Perry" <n_christopher_pe...@me.com> wrote: > Thank you John and Andy. I've got my machine working almost exactly the > way I want: When my spindle is enabled/disabled I have a oneshot triggering > a port pin connected to a modified wireless remote for my vacuum system. > > Now I just need to build a workaround for the ~4 s pulse I get on that > port pin when the computer is turned on... I'm guessing I need to wire in > a delay-on-make lockout for the vacuum remote connection that triggers on > some output on the computer. > > N.C. > > On 2012-Nov-12, at 05:01, andy pugh wrote: > > > On 12 November 2012 02:18, John Kasunich <jmkasun...@fastmail.fm> wrote: > > > >> "man oneshot" from the command line should get you the documentation. > > > > Or the HTML docs: > http://www.linuxcnc.org/docs/html/man/man9/oneshot.9.html > > Note that you can set it to produce a pulse on both the rising and > > falling edge, so if you net-ed it to halui.machine,is-on you would get > > a pulse when you turned the machine on or off (F2 key in axis) > > You need to enable halui to get that pin: > > http://www.linuxcnc.org/docs/html/gui/halui.html > > I don't know if you get the pulse, or how long it would be, if you > > exit LinuxCNC without turning the machine off. > > > > Note that oneshot has the time resolution of the thread it is in. So > > 1mS resolution in the typical servo thread. > > It can't run in the base thread. > > > > > > ------------------------------------------------------------------------------ > Keep yourself connected to Go Parallel: > DESIGN Expert tips on starting your parallel project right. > http://goparallel.sourceforge.net/ > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ Keep yourself connected to Go Parallel: BUILD Helping you discover the best ways to construct your parallel projects. http://goparallel.sourceforge.net _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
