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[gpsd-dev] [PATCH 3/5] Update C;ock Types section
From: |
Sanjeev Gupta |
Subject: |
[gpsd-dev] [PATCH 3/5] Update C;ock Types section |
Date: |
Mon, 16 Mar 2015 02:01:19 +0800 |
Minor changes
---
www/time-service-intro.txt | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/www/time-service-intro.txt b/www/time-service-intro.txt
index 6aca5c7..2ee1e5f 100644
--- a/www/time-service-intro.txt
+++ b/www/time-service-intro.txt
@@ -119,17 +119,17 @@ commonly claim 100 ns.
A plain GPS, without a stabilized crystal, can serve as a clock
source. However, it will generally be unable to deliver time at all when
it lacks memory of a previous 3D position fix and current lock on at
-least one satellite.
+least one satellite. In other words, it has no ''holdover''.
-GPSes actually deliver two times: 1PPS at top of second and in-band
+GPSes actually deliver two times: 1PPS at top of second, and in-band
time expressed in a message packet over the serial or USB link. In
-consumer-grade GPSes 1PPS may not be shipped to the serial connector;
+consumer-grade GPSes, 1PPS may not be shipped to the serial connector;
if it is, it becomes a pulse on a handshake line, usually DCD.
-In-band time is usually delivered to the second only and is shipped
-with significant and variable delay after 1PPS, typically on the order
-of 100 ms. By contrast, 1PPS time output total error will typically be
-close to 1μs.
+In-band time is usually delivered accurate to the second only and is
+shipped with significant and variable delay after 1PPS, typically on
+the order of 100 ms. By contrast, 1PPS time output total error will
+typically be close to 1μs.
== Basics of NTP ==
--
2.1.4