Roland Jollivet wrote: > > So what I'm wondering is why do the Mesa cards use 32 bit counters for the > encoders? > > Would a 16bit counter not suffice? It just seems that there is a lot of time > spent reading redundant numbers from encoders, and that things could be > simplified with 16 bits. > > I use a 24-bit counter on my parallel port-connected boards. Rollover definitely happens on systems with higher resolution or long travels, and is handled by the driver. The Mesa cards that plug into a PCI slot don't have to worry as much about the overhead of reading 32-bit registers. Rollover is less likely on those, but still possible. Yes, a 16-bit counter would have been sufficient on my boards, mostly I used 24 as that is what was provided by the Servo-to-Go board (LS7166 chips). I was trying to stay as close to the STG in functionality as I could.
But, I'm not sure moving down to a 16-bit counter is much of a simplification. Jon ------------------------------------------------------------------------------ The ultimate all-in-one performance toolkit: Intel(R) Parallel Studio XE: Pinpoint memory and threading errors before they happen. Find and fix more than 250 security defects in the development cycle. Locate bottlenecks in serial and parallel code that limit performance. http://p.sf.net/sfu/intel-dev2devfeb _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
