Section 7. Installation
271
•
increased runtime write performance
•
short card-eject times
Option 64
is unique among table file options in that it pre-allocates enough
memory on the memory card to store an interval amount of data
1
. Pre-allocation
allows data to be continuously and more quickly written to
the card in ≈1 KB
blocks. TOB3 binary format copies data directly from CPU memory to the
memory card without format conversion, lending additional speed and efficiency
to the data storage process.
Note
Pre-allocation of memory card files significantly increases run time
write performance. It also reduces the risk of file corruption that can occur
as a result of power loss or incorrect card removal.
Note
To avoid data corruption and loss, memory card removal must
always be initiated by pressing the
Eject
button on the face of the CR6.
The card must be ejected only after the
Act
light shows a solid green.
Q:
Why are individual files limited to 2 GB?
A:
In common with many other systems, the datalogger natively supports signed
four-byte integers. This data type can represent a number as large as 231, or in
terms of bytes, roughly 2 GB. This is the maximum file length that can be
represented in the datalogger directory table.
Q:
Why does a large card cause long program compile times?
A:
Program compile times increase with card and file sizes. As the datalogger
boots up, the card must be searched to determine space available for data storage.
In addition, for tables that are created by
TableFile()
with
Option 64
, an empty
file that is large enough to hold all of the specified records must be created (i.e.,
memory is pre-allocated). When using
TableFile()
with
Option 64
, program
compile times can be lessened by reducing the number of records or data-output
interval that will be included in each file. For example, if the maximum file size
specified is 2 GB, the datalogger must scan through and pre-allocate 2 GB of card
memory. However, if smaller files are specified, then compile times are reduced
because the datalogger is only required to scan through enough memory to
pre-allocate memory for the smaller file.
Q:
Why does a freshly formatted card cause long compile times?
A:
Program compile times take longer with freshly formatted cards because the
cards use a FAT32 system (File Allocation Table with 32 table element bits) to be
compatible with PCs. Because of the way the FAT32 card format works, you can
avoid long CR6 compile times with a freshly formatted card by first formatting
the new card on a PC, then copy a small file to the card from the PC, and then
delete the file with the PC. When the small file is copied to the card, the PC
updates a sector on the card that which allows the CR6 program to compile faster.
This only needs to be done once when the card is formatted. If you have the CR6
Summary of Contents for CR6 Series
Page 2: ......
Page 4: ......
Page 6: ......
Page 32: ......
Page 36: ......
Page 38: ......
Page 76: ...Section 5 Overview 76 FIGURE 20 Half Bridge Wiring Example Wind Vane Potentiometer ...
Page 80: ...Section 5 Overview 80 FIGURE 23 Pulse Input Wiring Example Anemometer ...
Page 136: ......
Page 454: ...Section 8 Operation 454 FIGURE 104 Narrow Sweep High Noise ...
Page 459: ...Section 8 Operation 459 FIGURE 106 Vibrating Wire Sensor Calibration Report ...
Page 535: ...Section 8 Operation 535 8 11 2 Data Display FIGURE 121 CR1000KD Displaying Data ...
Page 537: ...Section 8 Operation 537 FIGURE 123 CR1000KD Real Time Custom ...
Page 538: ...Section 8 Operation 538 8 11 2 3 Final Storage Data FIGURE 124 CR1000KD Final Storage Data ...
Page 539: ...Section 8 Operation 539 8 11 3 Run Stop Program FIGURE 125 CR1000KD Run Stop Program ...
Page 541: ...Section 8 Operation 541 FIGURE 127 CR1000KD File Edit ...
Page 546: ......
Page 552: ......
Page 610: ...Section 11 Glossary 610 FIGURE 137 Relationships of Accuracy Precision and Resolution ...
Page 612: ......
Page 648: ......
Page 650: ......
Page 688: ......
Page 689: ......