Document the change in polarity of the uart(4) PPS capture.
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@ -31,6 +31,20 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 11.x IS SLOW:
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disable the most expensive debugging functionality run
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"ln -s 'abort:false,junk:false' /etc/malloc.conf".)
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20150810:
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The polarity of Pulse Per Second (PPS) capture events with the
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uart(4) driver has been corrected. Prior to this change the PPS
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"assert" event corresponded to the trailing edge of a positive PPS
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pulse and the "clear" event was the leading edge of the next pulse.
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As the width of a PPS pulse in a typical GPS receiver is on the
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order of 1 millisecond, most users will not notice any significant
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difference with this change.
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Anyone who has compensated for the historical polarity reversal by
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configuring a negative offset equal to the pulse width will need to
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remove that workaround.
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20150809:
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The default group assigned to /dev/dri entries has been changed
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from 'wheel' to 'video' with the id of '44'. If you want to have
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