3 Data Logs
MiLLennium GPSCard SW Version 4.503/4.52 Command Descriptions Manual Rev 2 35
3 DATA LOGS

3.1 OUTPUT LOGGING

The GPSCard provides versatility in your logging requirements. You can direct your logs to either COM1 or
COM2, or both ports, as well as combine data types. The GPSCard has four major logging formats:
•NovAtel Format Data Logs (ASCII/Binary)
•NMEA Standard Format Data Logs (ASCII)
•RTCM Standard Format Data Logs (Binary)
•RTCA Standard Format Data Logs (Binary)
All data types can be logged using several methods of triggering each log event. Each log is initiated using the LOG
command. The LOG command and syntax are listed below.
Syntax:
log [port],datatype,[trigger],[period],[offset],{hold}
Example: log com1,posa,ontime,60,1
If the LOG syntax does not include a trigger type, it will be output only once following execution of the LOG
command. If trigger type is specified in the LOG syntax, the log will continue to be output based on the trigger
Syntax Description Example
LOG LOG
port COM1 or COM2 COM1
datatype Enter one of the valid ASCII or Binary Data Logs (see later in this chapter and Appendix D, Page 138)POSA
trigger Enter one of the following triggers.ONTIME
ONCE Immediately logs the selected data to the selected port once. Default if trigger field is left blank.
ONMARK Logs the selected data when a MARKIN electrical event is detected. Outputs internal buffers
at time of mark - does not extrapolate to mark time. Use MKBA/B for extrapolated position at
time of mark.
ONNEW Logs the selected data each time the data is new even if the data is unchanged.
ONCHANGED Logs the selected data only when the data has changed.
ONTIME
[period], [offset]Immediately logs the selected data and then periodically logs the selected data at a frequency
determined by the period and offset parameters. The logging will continue until an UNLOG
command pertaining to the selected data item is received (see UNLOG Command, Page 134).
CONTINUOUSLY Will log the data all the time. The GPSCard will generate a new log when the output buffer
associated with the chosen port becomes empty. The continuously option was designed for
use with differential corrections over low bit rate data links. This will provide optimal record
generation rates. The next record will not be generated until the last byte of the previous record
is loaded into the output buffer of the UART.
period Use only with the ONTIME trigger. Units for this parameter are seconds. The selected period may be any of the
following values: 0.05, 0.10, 0.20, 0.25, 0.50, 1, 2, 3, ... , 3600 seconds but may be limited by the GPSCard model
and previously requested logs. Selected data is logged immediately and then periodic logging of the data will start at
the next even multiple of the period. If a period of 0.20 sec is chosen, then data will be logged when the receiver time
is at the 0.20, 0.40, 0.60 and the next (0.80) second marks. If the period is 15 seconds, then the logger will log the
data when the receiver time is at even 1/4 minute marks. The same rule applies even if the chosen period is not
divisible into its next second or minute marks. If a period of 7 seconds is chosen, then the logger will log at the
multiples of 7 seconds less than 60, that is, 7, 14, 21, 28, 35, 42, 49, 56 and every 7 seconds thereafter.
60
offset Use only with the ONTIME trigger. Units for this parameter are seconds. It provides the ability to offset the logging
events from the above startup rule. If you wished to log data at 1 second after every minute you would set the period
to 60 seconds and the offset to 1 second (Default is 0).
1
hold Will prevent a log from being removed when the UNLOGALL command is issued HOLD
3 DATA LOGS