GPS Week Rollover on the OEM3 MiLLennium GPS Card

Q.] All our OEM3/MiLLennium GPS Card ASCII logs show the wrong GPS week number. For example, when we record the POSA log, the GPS week number is 447, while the newer OEM4/OEMV receivers show the GPS week of 1471. Is there is solution for this?

A.] There is a command in OEM3/MiLLennium FW 4.503 called ROLLOVER, which allows you to manipulate the way that the OEM3 handles the GPS week rollover:

Syntax: ROLLOVER FLAG ..where: FLAG = ENABLE Week number will rollover to 0 = DISABLE Week number will continue to count up log posa $POSA,447,234986.00,51.11671069,-114.03878432,1062.749,-16.271,61,1.703,1.329,3.527,0*1E rollover disable log posa $POSA,1471,234996.00,51.11671109,-114.03878606,1062.533,-16.271,61,1.679,1.311,3.488,0*25 ROLLOVER is ENABLE'd by default, causing the current GPS week to report as "447". When the ROLLOVER DISABLE command is used, the current GPS week will report "1471" instead. If you want the OEM3 to remember the ROLLOVER DISABLE setting through a power cycle (or RESET command), you can use the SAVECONFIG command to save this setting to NVRAM. FRESET will clear this setting back to its factory default of ROLLOVER ENABLE.

The ROLLOVER command is no longer valid. If this command is used, the week number will be reported as the same 10bit week number.