Specifications

Section 12. Memory and Data Storage
12-4
12.1 Internal SRAM
SRAM (2 or 4 Mbytes) is powered by the internal CR1000 battery when main
power is disconnected so data remain in memory. SRAM data are erased when
a program is sent to the CR1000. Some SRAM is used by the operating
system.
The CR1000 can be programmed to store each measurement or, more
commonly, to store processed values such as averages, maxima, minima,
histograms, FFTs, etc. Storage can be programmed to occur periodically or
conditionally. Data are stored in data tables in SRAM as directed by the
CRBASIC program (Section 9.5 Structure). A data table can be configured as
ring
memory or fill-and-stop. Ring memory allows the CR1000 to overwrite
the oldest data when the data table is full. Fill-and-stop configures the data
table to be filled, then subsequent data discarded.
In a CRBASIC program, the DataTable() instruction sets the size of the data
table or buffer area. A data file mirroring an SRAM data table can be stored on
a CF card by including the CardOut() instruction within the data table
declaration. When a CF card is used, SRAM also acts as the buffer area for
data written to the card.
12.2 CompactFlash
®
(CF)
When installing or removing the CFM100 or NL115
module, first turn off CR1000 power.
Removing a card from the CFM100 or NL115 while the CF
card is active can cause garbled data and can actually
damage the card. Always press the button to disable the
card for removal and wait for the green LED before
switching off the CR1000 power.
To prevent losing data, collect data from the CF card
before sending a program to the datalogger. When a
program is sent to the datalogger all data on the CF card is
erased.
CSI CF card modules connect to the CR1000 Peripheral Port. Each has a slot
for a Type I or Type II CF card. A CF card expands the CR1000’s storage
capacity. A maximum of 30 data tables can be created on a CF card.
CardConvert software, included with LoggerNet, PC400,
RTDAQ, and PC200W support software, converts CF 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 will be 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.
CAUTION
NOTE