Campbell CR800 Series, Operator'S Manual, Page: 420 / 598

Section 8. Operation
420
A second instance of a setting can be configured using the same node PakBus
address and same file type, in which case two files will be written according to
each of the two settings. For example,
(55,USR:photo.JPG,100)
(55:USR:NewestPhoto.JPG,0)
will store two files each time a JPG file is received from node 55. They will be
named USR:photonnn.JPG and USR:NewestPhoto.JPG. This feature is used
when a number of files are to be retained, but a copy of one file whose name
never changes is also needed. The second instance of the file can also be
serialized and used when a number of files are to be saved to different drives.
Entering 3212 as the PakBus address activates storing IP trace information to a
file. The "number of files" parameter specifies the size of the file. The file is a
ring file, so the newest tracing is kept. The boundary between newest and oldest
is found by looking at the time stamps of the tracing. Logged information may
be out of sequence.
Example:
(3212, USR:IPTrace.txt, 5000)
This syntax will create a file on the USR: drive called IPTrace.txt that will grow
to approximately 5 KB in size, and then new data will begin overwriting old data.
8.8.4.3 Data Preservation
Associated with file attributes is the option to preserve data in CR800 memory
when a program is sent. This option applies to final-storage data SRAM, memory
cards, and datalogger support software
(p. 86)
cache data
(p. 494).
Depending on the
application, retention of data files when a program is downloaded may be
desirable. When sending a program to the CR800 with datalogger support
software Send command, data are always deleted before the program runs. When
the program is sent using support software File Control Send
(p. 498)
command or
CRBasic Editor
Compile, Save and Send
(p. 494)
command, options to preserve
(not erase) or not preserve (erase) data are presented. The logic in the following
example summarizes the disposition of CR800 data depending on the data
preservation option selected.
if "Preserve data if no table changed"
if current program = overwritten program
keep CPU data
keep cache data
else
erase CPU data
erase cache data
end if
end if
if "erase data"
erase CPU data
erase cache data
end if