Campbell Scientific CR9000X Measurement and Control System - Manual (Page 187)

Section 6. Data Table Declarations and Output Processing Instructions
required would be 6400 bytes (Lapse x 16 Bytes/Sub-header = 6400 bytes). If
the data frames were 1 kByte, then 7 additional data frames would be allocated
for the Data Table.
If more lapses occur than have been allocated for, new Lapse
sub-headers will still be inserted into the data frames using up
memory that was originally allocated for data records. The
consequence of this is that the actual number of records written to
the data table may be less than what was specified in the
DataTable and/or CardOut instructions. NOTE
Entering 0 for the Lapses parameter forces every record to include a
record number and timestamp, requiring an additional 16 bytes per
record. If data storage space is not an issue, this option should be used.
Entering a negative number for the Lapses parameter
sets the CR9000X not to adjust for lapses. Only the periodic
data frame header time stamps (approximately once per 1
KByte of data) are inserted. If a lapse occurs, a sub-header
with time stamp will NOT be inserted, and the timestamps
for subsequent records in that data frame will be generated
incorrectly at data collection. CAUTION
Parameter
& Data Type Enter DATAINTERVAL PARAMETERS
TintoInt
Constant
The time into the interval (offset to the interval) at which the table is to be output. The units for time are
the same as for the interval.
Interval
Constant
Enter the time interval on which the data in the table is to be recorded. The interval may be in µseconds,
milliseconds, seconds, minutes, hours or days, whichever is selected with the Units parameter. Enter 0
to make the data interval the same as the scan interval.
Units The units for the time parameters, PowerOff is the only instruction that uses hours or days.
Constant Alpha
Code Numeric
Code
Units
USEC 0 Microseconds
MSEC 1 Milliseconds
SEC 2 Seconds
MIN 3 Minutes
HR 4 Hours
Day 5 Days
As each new record is stored, time is checked to ensure that the interval is correct. The datalogger keeps
track of lapses or discontinuities in the data.
Lapse Value
Result
Lapses > 0 If table record number is fixed, number of additional data frames allocated to
data table if memory is available. If record number is auto-allocated, no
memory is added to table.
Lapses = 0 Timestamp always stored with each record.
Lapses
Constant
Lapses < 0 When lapse occurs, sub-header w/ timestamp not inserted. Record timestamps
calculated at data extraction may be in error.
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