Chris Radek wrote:
> On Thu, Jul 05, 2007 at 11:36:40AM -0500, Stuart Stevenson wrote:
> 
>>Gentlemen,
>>    The screenshots are on imagebin.org under stustev. They are
>>representative of the previously presented scenario of homing
>>attempts. aligned, .030, and .060.
>>thanks
>>Stuart
> 
> 
> It looks to me that you are getting more index pulses than you
> should.  At first glance I don't think this is a problem with the
> new homing method.
> 
Form the one posted picture, that isn't clear.  He has a home 
position with an offset from the index pulse.  That is that 
final, fast ramp on the position.
> If you have the latest ppmc firmware chip (?), I'm pretty sure
> the ppmc is working right from seeing Jon's device at Workshop.
> In that case, maybe you should get out the (real) scope and check
> for noise on your encoder lines right at the ppmc inputs.
That is good advice, but a posted screenshot with the 
ppmc.0.encoder.0x.index    pin displayed would be helpful.  It 
could be extra index pulses, and they should show up in 
halscope, too, if present.  But, I suspect something else is 
going on.  You might try backing off an inch or so and homing a
couple of times.  If that IS repeatable, then something about 
starting a home sequence VERY close to the home position may be 
the clue.  Also, if you can try having the HOME_LATCH_VELOCITY 
the same polarity as HOME_SEARCH_VELOCITY, and see if that makes 
a difference.  The more we can narrow down what the conditions 
are that cause the problem, the more it steers us to the source 
of the trouble.

Jon

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