diff options
-rw-r--r-- | www/replacing-nmea.xml | 24 |
1 files changed, 14 insertions, 10 deletions
diff --git a/www/replacing-nmea.xml b/www/replacing-nmea.xml index 56d9dad5..7c4e0dbd 100644 --- a/www/replacing-nmea.xml +++ b/www/replacing-nmea.xml @@ -60,6 +60,14 @@ Added GPSVID and GPSGP, changed to mandate ISO8601 dates. </revremark> </revision> + <revision> + <revnumber>1.3</revnumber> + <date></date> + <authorinitials>esr</authorinitials> + <revremark> + Fixed timestamp to Zulu time. Specified signed latitude. + </revremark> + </revision> </revhistory> <abstract> @@ -239,10 +247,8 @@ not expect to ever ship valid information for this field.</para> <para>The first field of every sentence is a full timestamp in the format of the <ulink url='http://www.w3.org/TR/NOTE-datetime'>W3C -profile of ISO 8601</ulink>: that is, yyyy-mm-ddThh:mm:ss.sssTZD, -where TZD is a time zone designator (Z or +hh:mm or -hh:mm). -Millisecond or better precision is required and time must have -leap-second correction. Zulu or UTC time is recommended.</para> +profile of ISO 8601</ulink>, with the timezone required to be Zulu +(UTC) time.</para> <para>The core sentence of SGPS has the following layout:</para> @@ -260,14 +266,12 @@ The second field is the uncertainty of the timestamp in (fractional) seconds. </para></listitem> <listitem><para> -The third field is latitude in degrees. It must be suffixed with one -of 'N' for North or 'S' for South. Encoding must be decimal +The third field is signed latitude in degrees. Encoding must be decimal degrees, not degree/minute/second. </para></listitem> <listitem><para> -The fourth field is longitude in degrees. It must be suffixed with one -of 'E' for East or 'W' for West. Encoding must be decimal +The fourth field is signed longitude in degrees. Encoding must be decimal degrees, not degree/minute/second. </para></listitem> @@ -325,8 +329,8 @@ $GPTPV,2005-02-11T04:40:51.231Z,?,4916.45N,123.12W,2.3,70.1,52.0,01.0,02.1,23.1, 2005-02-11T04:40:51.231Z, Time (Feb 11 04:40:51 EST 2005) ?, Timestamp uncertainty will never be reported - 4916.45N, Latitude - 123.12W, Longitude + -4916.45, Latitude (- sign indicates longitude west) + 123.12, Longitude (- sign indicates latitude south) 2.3, Meters of horizontal uncertainty of position 70.1, Altitude, meters above sea level 52, Uncertainty of altitude |