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[gpsd-dev] [PATCH] Proofread the PPP doc.
From: |
Sanjeev Gupta |
Subject: |
[gpsd-dev] [PATCH] Proofread the PPP doc. |
Date: |
Sun, 23 Dec 2018 03:00:17 +0800 |
---
www/ppp-howto.adoc | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/www/ppp-howto.adoc b/www/ppp-howto.adoc
index e85e72f6..be496d3e 100644
--- a/www/ppp-howto.adoc
+++ b/www/ppp-howto.adoc
@@ -68,7 +68,7 @@ spot?
All GNSS systems compute positions using ECEF (earth-centered,
earth-fixed) coordinates. After an ECEF position is calculated, it is
-converted into latitude, longitude using a datum. So many to
+converted into latitude and longitude using a datum. So many to
choose from. You've probably heard of WGS84, NAD83, and maybe ITRF.
NAD83 is pinned to the North American tectonic plate. WGS84 is pinned
@@ -96,7 +96,7 @@ Original ITRF and WGS84 differ by less than 1 meter, which is
huge
for the purposes here. ITRF2014 and WGS84(G1762) differ by a few
centimeters.
-It gets worse. two expensive GPS often differ in altitude by over 60
+It gets worse. Two expensive GPS often differ in altitude by over 60
feet. Altitude is calculated as height above Mean Sea Level (MSL). But
the Earth is not a perfect sphere. It is more pear shaped. In addition
gravitational anomalies affect 'sea level'.
@@ -145,7 +145,7 @@ There are many possible adjustments to the above procedure.
Maybe you want to collect just 10 minutes of data to verify that your
tool-chain is working before doing a 24 hour run. Simple, just change
-`gpsprof -n 86400` to `gpsprof -n 360` and then proceed as above.
+`gpsprof -n 86400` to `gpsprof -n 600` and then proceed as above.
Maybe your _gpsd_ host does not have Python installed. Just run _gpsprof_
remotely. On the host you will need to run _gpsd_ with the `-g` parameter so
@@ -295,16 +295,17 @@ and QZSS:
...................................
$ zerk -d COMPASS
$ zerk -d GALILEO
+$ zerk -d GLONASS
$ zerk -d SBAS
$ zerk -e GPS
...................................
-Verify that only GPS and QZSS are enabled:
+Verify that only GPS and (possibly) QZSS are enabled:
...................................
$ zerk -p CONS
zerk: poll CONS
-RE: %cons%/par/pos/sys={gps=y,glo=y,gal=n,sbas=n,qzss=n,comp=n,irnss=n}
+RE: %cons%/par/pos/sys={gps=y,glo=n,gal=n,sbas=n,qzss=n,comp=n,irnss=n}
...................................
Verify raw data messages are being sent:
--
2.19.1
- [gpsd-dev] [PATCH] Proofread the PPP doc.,
Sanjeev Gupta <=