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6 data file formats – Campbell Scientific CR1000 Measurement and Control System User Manual

Page 335

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Section 8. Operation

335

 

Campbell Scientific CF card modules connect to the CR1000 peripheral port.
Each has a slot for Type I or Type II CF cards. A maximum of 30 data tables can
be created on a CF card. Refer to Writing High-Frequency Data to CF Cards

(p.

266)

for information on programming the CR1000 to use CF cards. Refer to the

appendix Card-Storage Modules

for information on available CF-card modules.

Note CardConvert software, included with mid- and top-level datalogger support
software

(p. 399, p. 451),

converts binary card data to the standard Campbell Scientific

data format.

When a data table is sent to a CF card, a data table of the same name in SRAM is
used as a buffer for transferring data to the card. When the card is present, the
Status table will show the size of the table on the card. If the card is removed, the
size of the table in SRAM is shown.

When a new program is compiled that sends data to the CF card, the CR1000
checks if a card is present and if the card has adequate space for the data tables. If
no card is present, or if space is inadequate, the CR1000 will warn that the card is
not being used. However, the user program runs anyway and data are stored to
SRAM. When a card is inserted later, data accumulated in the SRAM table are
copied to the CF card.

Formatting CF Cards

The CR1000 accepts cards formatted as FAT or FAT32; however, FAT32 is
recommended
. Otherwise, some functionality, such as the ability to manage large
numbers of files (>254) is lost. Older CR1000 operating systems formatted cards
as FAT or FAT32. Newer operating systems always format cards as FAT32.

To save time, use a PC to format CF cards. After formatting the card, write any
file to the card, then delete the file. This action sets up the card for faster initial
use.

FAT32 uses an “info sector” to store the free cluster information. This info sector
prevents the need to repeatedly traverse the FAT for the bytes free information.
After a card is formatted by a PC, the info sector is not automatically updated.
Therefore, when the datalogger boots up, it must determine the bytes available on
the card prior to loading the Status table. Traversing the entire FAT of a 16 GB
card can take up to 30 minutes or more. However, subsequent compile times are
much shorter because the info sector is used to update the bytes free information.
To avoid long compile times on a freshly formatted card, format the card on a PC,
then copy a small file to the card, and then delete the file (while still in the PC).
Copying the file to the freshly formatted card forces the PC to update the info
sector. The PC is much faster than the datalogger at updating the info sector.

8.3.1.1.6 Data File Formats

TableFile() instruction data-file formats contain time-series data and may have an
option to include header, time stamp and record number. Table TableFile()-
Instruction Data-File Formats

(p. 336)

lists available formats. For a format to be

compatible with datalogger support software

(p. 77)

graphing and reporting tools,

header, timestamps, and record numbers are usually required. Fully compatible
formats are indicated with an asterisk. A more detailed discussion of data file
formats is available in the Campbell Scientific publication LoggerNet Instruction
Manual
available at www.campbellsci.com.