13. Data memory
The data logger includes three types of memory: RAM, Flash, and Serial Flash.
13.1 Data tables
Measurement data is primarily stored in data tables. Data is usually erased from this area when a
program is sent to the data logger. Final-data memory for the CR300 series is organized in 4 KB
sectors of serial flash. Each sector is rated for 100,000 serial flash erases.
During data table initialization, memory sectors are assigned to each data table according to the
parameters set in the program. Program options that affect the allocation of memory include the
Size
parameter of the
DataTable()
instruction, the
Interval
and
Units
parameters of
the
DataInterval()
instruction. The data logger uses those parameters to assign sectors in a
way that maximizes the life of its memory. See the CRBasic Editor help for detailed instruction
information and program examples:
https://help.campbellsci.com/crbasic/cr300/.
By default, data memory sectors are organized as ring memory. When the ring is full, oldest data
is overwritten by newest data. Using the
FillStop
statement sets a program to stop writing to
the data table when it is full, and no more data is stored until the table is reset. To see the total
number of records that can be stored before the oldest data is overwritten, or to reset tables, go
to Station Status > Table Fill Times in your data logger support software.
Data concerning the data logger memory are posted in the Status and DataTableInfo tables. For
additional information on these tables, see
Information tables and settings (advanced)
For additional information on data logger memory, visit the Campbell Scientific blog
article, "
How to Know when Your Datalogger Memory is Getting Full
."
13.2 Flash memory
The data logger operating system is stored in a separate section of flash memory. To update the
operating system, see
Serial flash memory holds the CPU drive, web page, and data logger settings. Because flash
memory has a limited number of write/erase cycles, care must be taken to avoid continuously
writing to files on the CPU drive.
13. Data memory
66