Campbell CR3000 Micrologger, Руководство оператора

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Section 8. Operation
446
8.8.1.1.1 Data Table SRAM
Primary storage for measurement data are those areas in SRAM allocated to data
tables as detailed in table CR3000 SRAM Memory
(p. 444,
http://www.
).
Measurement data can be also be stored as discrete files on USR: or USB: by
using TableFile() instruction.
The CR3000 can be programmed to store each measurement or, more commonly,
to store processed values such as averages, maxima, minima, histograms, FFTs,
etc. Data are stored periodically or conditionally in data tables in SRAM as
directed by the CRBasic program (see Program Structure
(p. 129)
). The
DataTable() instruction allows the size of a data table to be programmed.
Discrete data files are normally created only on a PC when data are retrieved
using datalogger support software
(p. 90).
Data are usually erased from this area when a program is sent to the CR3000.
However, when using support software File Control menu Send
(p. 539)
command
or CRBasic Editor Compile, Save and Send
(p. 534)
command, options are
available to preserve data when downloading programs.
8.8.1.1.2 CPU: Drive
CPU: is the default drive on which programs and calibration files are stored. It is
formatted as FAT32. Do not store data on CPU: or premature failure of memory
will probably result.
8.8.1.1.3 USR: Drive
SRAM can be partitioned to create a FAT32 USR: drive, analogous to partitioning
a second drive on a PC hard disk. Certain types of files are stored to USR: to
reserve limited CPU: memory for datalogger programs and calibration files.
Partitioning also helps prevent interference from data table SRAM. USR: is
configured using DevConfig settings or SetStatus() instruction in a CRBasic
program. Partition USR: drive to at least 11264 bytes in 512-byte increments. If
the value entered is not a multiple of 512 bytes, the size is rounded up. Maximum
size of USR: 2990000 bytes.
USR: is not affected by program recompilation or formatting of other drives. It
will only be reset if the USR: drive is formatted, a new operating system is
loaded, or the size of USR: is changed. USR: size is changed manually by
accessing it in the Status table or by loading a CRBasic program with a different
USR: drive size entered in a SetStatus() or SetSetting() instruction. See
CRBasic Program — Setup Tools
(p. 118).
Measurement data can be stored on USR: as discrete files by using the
TableFile() instruction. Table TableFile() Instruction Data File Formats
(p. 449)
describes available data-file formats.
Note Placing an optional USR: size setting in the CRBasic program over-
rides manual changes to USR: size. When USR: size is changed
manually, the CRBasic program restarts and the programmed size for
USR: takes immediate effect.