Trimble Outdoors Part Number 45005-00-ENG manual Acutime 2000 Synchronization Kit User Guide

Trimble Standard Interface Protocol A

number roll-over occurred as August 21, 1999 (GPS) transitioned to August 22, 1999 (GPS). The ACE UTC GPS adjusts for this week rollover by adding 1024 to any week number reported by GPS that is less than week number 1023, which began on December 14, 1997. With this technique, the ACE UTC GPS will provide an accurate translation of GPS week number and TOW to time and date until July 30, 2017.

UTC Offset: This field represents the current integer leap second

offset between GPS and UTC according to the relationship: Time (UTC) = Time (GPS) - UTC Offset. The UTC offset information is reported to ACE UTC GPS by the GPS system and can take up to

12.5minutes to obtain. Before the ACE UTC GPS has received UTC information from the GPS system, it is only capable of representing time in the GPS time scale, and the UTC offset will be shown as 0.

Timing Flags: This field is bitwise encoded to provide information about the timing outputs. Unused bits should be ignored.

Bit 0: When 0, the date and time fields broadcast in packet 0x8F-AB are in the GPS time scale. When 1, these fields are in the UTC time scale and are adjusted for leap seconds.

Bit 2: When 0, time has been set from GPS. When 1, time has not yet been set from GPS.

Bit 3: When 0, UTC offset information has been received. When 1, UTC offset information is not yet known.

Time of Day: The time of day is sent in hours-minutes- seconds format and varies from 00:00:00 to 23:59:59, except when time is in UTC and a leap second insertion occurs. In this case the time will transition from 23:59:59 to 23:59:60 to 00:00:00.

Date: The date is sent in day-month-year format.

A-116 Acutime 2000 Synchronization Kit User Guide