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The above sequence shows that the system clock is behind the GPS. The system time when the interrupt function is being called on the PPS assert is 5 microseconds before the exact second (0.999995). This corresponds to a NTPClockOffset of a positive 5 microseconds. This is confirmed with the ntpq program (which reports its offset in milliseconds):

Code Block
ntpd -p
root@manitou root# ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
xral             38.229.71.1      3 u   34   64  377    0.320    3.804   0.031
 LOCAL(0)        .LOCL.          10 l  93d   64    0    0.000    0.000   0.000
oGPS_NMEA(0)     .GPS.            2 l    6   16  377    0.000    0.005   0.031

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