On Monday 03 February 2020 19:46:30 andy pugh wrote: > On Fri, 31 Jan 2020 at 17:38, Jon Elson <[email protected]> wrote: > > Hmmm, some interesting things to note. His input scale is > > 85333.33 counts/inch. > > 85333 * 50331 looks like it is very close to a 32-bit > > rollover (4294895223). > > The PPMC devices use a 24-bit hardware counter, and then > > rollover and extension to > > a 32-bit integer is handled in the ppmc driver. > > Is he using a 64-bit kernel? The size of integers might have changed. > (I thought the drivers actually expanded to 64 bit internally? HAL > stepgen and the Mesa drivers do. I can just about imagine a high-speed > spindle encoder wrapping at 32 bits) > > Anyway, I would point the finger of suspicion here: > https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/drivers/hal_p >pmc.c#L1080 > > It uses a Union which contains 4 bytes and a "signed long" but "long" > is only "at least 32 bits". Some web searching seems to suggest that > "long" is 4 bytes in a 32 bit OS and 8 bytes in a 64-bit OS. > > If your customer is using a 64-bit OS then he has found a bug, and one > we may need to squash in many places.
Just muttering to myself, but it sounds like I may have already hit that, I couldn't get my armhf versions of master to install an a 64 bit debian arm64 install. So I went to raspbian, which is still armhf for a default buster install. And thats working fairly well on an rpi4. 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) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
