From e7dbaf581e2b40c73370d2f9e1ec79db2f94b44c Mon Sep 17 00:00:00 2001 From: Ian Lepore Date: Mon, 10 Aug 2015 21:09:06 +0000 Subject: [PATCH] Document the change in polarity of the uart(4) PPS capture. --- UPDATING | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/UPDATING b/UPDATING index bd2d45d53e8e..ce6973da7f4e 100644 --- a/UPDATING +++ b/UPDATING @@ -31,6 +31,20 @@ NOTE TO PEOPLE WHO THINK THAT FreeBSD 11.x IS SLOW: disable the most expensive debugging functionality run "ln -s 'abort:false,junk:false' /etc/malloc.conf".) +20150810: + The polarity of Pulse Per Second (PPS) capture events with the + uart(4) driver has been corrected. Prior to this change the PPS + "assert" event corresponded to the trailing edge of a positive PPS + pulse and the "clear" event was the leading edge of the next pulse. + + As the width of a PPS pulse in a typical GPS receiver is on the + order of 1 millisecond, most users will not notice any significant + difference with this change. + + Anyone who has compensated for the historical polarity reversal by + configuring a negative offset equal to the pulse width will need to + remove that workaround. + 20150809: The default group assigned to /dev/dri entries has been changed from 'wheel' to 'video' with the id of '44'. If you want to have