I am not sure about this problem, but there is the SirfStarIII GPS chip in the Magellan Triton 500. This chip can communicate with Triton hardware and software using NMEA data transfer protocol or Sirf Binary protocol. This device using NMEA for normal working process, where an information from GPS chip to CPU is transmitting as a simple text messages. You can find a list of NMEA messages in the Internet. Here are some of this messages
RMC - NMEA has its own version of essential gps pvt (position, velocity, time) data. It is called RMC, The Recommended Minimum, which will look similar to:
$GPRMC,123519,A,4807.038,N,01131.000,E,022.4,084.4,230394,003.1,W*6A
Where: RMC Recommended Minimum sentence C 123519 Fix taken at 12:35:19 UTC A Status A=active or V=Void. 4807.038,N Latitude 48 deg 07.038' N 01131.000,E Longitude 11 deg 31.000' E 022.4 Speed over the ground in knots 084.4 Track angle in degrees True 230394 Date - 23rd of March 1994 003.1,W Magnetic Variation *6A The checksum data, always begins with *
ZDA - Data and Time
$GPZDA,hhmmss.ss,dd,mm,yyyy,xx,yy*CC $GPZDA,201530.00,04,07,2002,00,00*60
where: hhmmss HrMinSec(UTC) dd,mm,yyyy Day,Month,Year xx local zone hours -13..13 yy local zone minutes 0..59 *CC checksum
So, there are "day", "month", "year" data fields, but there is no "week" field.
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