Right now my test set up is going to consist of a 6i25, 7i85 and an 8i20. I wonder if the 7i85 could expose a BSPI interface. Or could I tack a BSPI on to the 6i25's spare 25 pin connector?
I also am considering just writing a parallel port driver running at some higher rate than the servo thread that would allow me to communicate with the spi device. On Wed, Sep 18, 2019 at 9:36 AM Curtis Dutton <[email protected]> wrote: > Chris thanks for the info. > > I'm not exactly certain at this point what precision I need. I'll be > determining that experimentally later. I will keep in mind what you have > said, I'll deal with it after I get my hardware running. > > > On Tue, Sep 17, 2019 at 6:17 PM Chris Albertson <[email protected]> > wrote: > >> If you want better than 16-bits and 1KHz then you also are going to need a >> very good quality analog signal conditioning and instrumentation >> amplifier. >> The analog circuit between the A/D converts and the load cell really >> does >> matter. You have to reject common-mode or the low bits will just be >> filled with 60Hz noise. And you can not simply use a "brick wall" filter >> or you will not get the desired bandwidth through. (If you are needing to >> sample at 1K then you must care about 500Hz bandwidth. >> >> This matters a LOT more than which A/D chip you use. >> >> 22 bits is better than one part per million. Do you really need that? It >> will be hard to isolate all of the electrical and mechanical noise >> especially >> >> On Tue, Sep 17, 2019 at 2:26 PM Curtis Dutton <[email protected]> wrote: >> >> > I have a pet project I'm starting that will involve reading a load cell >> in >> > as near as real time as possible and using that input for servo control. >> > >> > I plan on using mesa hardware to interface to the equipment. Does anyone >> > know of a nice way to interface hotsmot2 to a load cell? >> > >> > I would like a fairly high resolution. 16 bit minimum, the higher the >> > better up to 22 bit I suppose. As well as the ability to sample at the >> > servo thread rate of 1 Khz. >> > >> > >> > Thanks, >> > Curtis >> > >> > _______________________________________________ >> > Emc-users mailing list >> > [email protected] >> > https://lists.sourceforge.net/lists/listinfo/emc-users >> > >> >> >> -- >> >> Chris Albertson >> Redondo Beach, California >> >> _______________________________________________ >> Emc-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/emc-users >> > _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
