Attached is a plot of the timing message arrival times of the Trimble Resolution-T receiver running in TSIP mode. Like the Adafruit Ultimate, its firmware seems to do little to get the timing message out at a fixed reference point.
As Tom pointed out, this is only an issue if you are trying to synchronize or time-stamp something (like a time display) to UTC and cannot make use of the 1PPS signal. Lady Heather has a "poor mans" NTP-ish function that can set the system clock on a periodic basis or whenever the system time diverges from the receiver time by "x" milliseconds... very handy if you are out in the boonies without a net connection. Having a receiver with a consistent and known timing message offset is important for maximum accuracy when doing this. A Windows XP system clock can be kept within 40 msecs of actual time (their time-setting/reading accuracy is +/- 15.6 msecs).
Attached is a plot of the timing message arrival times of the Trimble Resolution-T receiver running in TSIP mode. Like the Adafruit Ultimate, its firmware seems to do little to get the timing message out at a fixed reference point.
As Tom pointed out, this is only an issue if you are trying to synchronize or time-stamp something (like a time display) to UTC and cannot make use of the 1PPS signal. Lady Heather has a "poor mans" NTP-ish function that can set the system clock on a periodic basis or whenever the system time diverges from the receiver time by "x" milliseconds... very handy if you are out in the boonies without a net connection. Having a receiver with a consistent and known timing message offset is important for maximum accuracy when doing this. A Windows XP system clock can be kept within 40 msecs of actual time (their time-setting/reading accuracy is +/- 15.6 msecs).
