Tom Easterday wrote: > On Nov 30, 2010, at 2:28 PM, andy pugh wrote: > >> On 30 November 2010 19:22, Tom Easterday <tom-...@bgp.nu> wrote: >> >> >>> Also, Jeff mentioned moving at a snails pace...we will be moving slowly >>> during homing. We would get near home, find index pulse while moving >>> slowly… >>> >> You can probably synthesise a nice accurate home signal by and-ing the >> limit switch and index together. >> > > Andy, > That is a good idea. And, am I to assume that that means a physical home > switch alone is no more (or less) accurate than the index pulse? > No. With hardware encoder counters, you can zero the hardware count when the index pulse is seen, such that it is always accurate to +/- one encoder count, or maybe even better, depending on whether the index is gated by the A signal. This can even be done at very high speeds, although this step is not likely to actually be done while moving at rapid speed. The problem with anding home and index is then the home signal becomes a VERY narrow pulse, and could be missed, same as before. I don't think this would solve any problem.
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