Guralp Systems CMG-DM24 - Manual (Page 93)

Operator's guide
fix. If Missing PPS is displayed in this field, the digitizer has
received fewer than 60 pulses on the 1pps (pulse per second)
line in the last minute. You will see at least one Missing PPS
message in the first minute of operation.
Every 20 minutes, at 10, 30 and 50 minutes past the hour, the GPS
synchronization status is displayed. This line has the same format as
the GPS line in the heartbeat message, e.g.
2005 8 10 12:41:01 326 MicroSeconds Slow Freq error -7 e-9 Auto
3-D [-4]
Finally, every hour, the DM24 displays general timing and position
information, including details of the visibility of GPS satellites:
2005 6 8 11:00:00 GPS Date/Time 08/06/05 11:00:00
2005 6 8 11:00:00 Auto 3-D SV#'s 4 7 13 20 23 24 25 ( 7 )
2005 6 8 11:00:00 Lat 51'21.6591N Long 001'09.8218W
SV# stands, officially, for Space Vehicle number. Each GPS satellite
has it's own unique identification number, or SV#, and the list shows
which are currently usable (satellite numbers 4, 7, 13, 20, 23, 24 and
25 in this example). A minimum of four is required to obtain a full 3-
dimensional GPS fix.
Trigger notifications
When a trigger occurs, a message is immediately saved to the current
status block. You may not see this message straight away, however,
since the status block must be full before the digitizer will send it.
2006 1 18 14:48:36 SOFTWARE Trigger : Trigger# 22
The trigger type is mentioned, as well as the sequence number (for
later retrieval, if necessary, using the EVENTSLIST command). When
the trigger condition ends, the system reports
2006 1 18 14:49:10 End of Trigger
Environmental measurements
These are measured every 10 minutes (at 5, 15, 25, 35, 45 and 55
minutes past the hour), and are given in the same form as for heartbeat
messages:
2006 1 18 14:45:00 External supply : 13.0V Temperature 24.62'C
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