Campbell Scientific CR23X Micrologger - Manual (Page 67)

SECTION 4. EXTERNAL STORAGE PERIPHERALS
4-3
TABLE 4.2-1. 8 Mode Entries
Display ID:
Key DATA Description
∗ 8 Mode 08: Storage Area Key 1 or 2 for Storage Area. (This window is skipped if no memory
00 has been allocated to Final Storage Area 2.)
A 01: Device Code Key in Output Device Option. See Table 4.1-1.
XX
A
02: Start Location Start of dump location. Initially the SPTR or PPTR location; a
XXXXX different location may be entered if desired.
A 03: End Location End of dump location. Initially the DSP location; a different location
XXXXX may be keyed in if desired.
A 04: Number Starts Ready to dump. To initiate dump, key any number, then A. While
00
dumping, "04 activated; key aborts" and the location number will be
displayed. “Output complete” will be displayed when the dump is
complete. (Any key aborts transmission after completion of the
current data block.)
4.2 MANUALLY INITIATED DATA
OUTPUT - 8 MODE
Data transfer to a peripheral device can be
manually initiated in the
8 Mode. The
8 Mode allows the user to retrieve a
specific block of data, on demand, regardless of
whether or not the CR23X is programmed for
on-line data output.
If external storage peripherals are not left on-
line, the maximum time between collecting data
must be calculated to ensure that data in Final
Storage are not lost due to write-over. To
calculate this time it is necessary to know: (1)
the size of Final Storage, (2) the number of
Output Arrays being generated, (3) the number
of low and/or high resolution data points per
Output Array, and (4) the rate at which Output
Arrays are placed into Final Storage. When
calculating the number of data points per
Output Array, remember to add 1 data point per
array for the Output Array ID.
For example, assume that 586,568 locations are
assigned to Final Storage (
A Mode), and
that 1 Output Array, containing the Array ID (1
memory location), 9 low resolution data points (9
memory locations) and 5 high resolution data
points (10 memory locations), is stored each
hour. In addition, an Output Array with the Array
ID and 5 high resolution data points (11 memory
locations) is stored daily. This is a total of 491
memory locations per day ((20 x 24) + 11).
586,568 divided by 491 = 1194 days. Therefore,
the CR23X would have to be visited every 1194
days to retrieve data, because write-over would
begin on the 1195th day. The site should be
visited more frequently than this for routine
maintenance. Thus data storage capacity would
not be a factor in determining how frequently to
visit the site.
The output device codes used with the 8
Mode are the same as those used with
Instruction 96 (Table 4.1-1), with the exception
of the option to transfer data from one Final
Storage area to the other (80, 81). Table 4.2-1
lists the keystrokes required to initiate a
8
data dump.
4.3 PRINTER OUTPUT FORMATS
Printer output can be sent in binary Final Storage
Format (Appendix C.2), Printable ASCII, or
Comma Separated ASCII. These ASCII formats
may also be used when data from the Storage
Modules or Telecommunications are stored on
disk with Campbell Scientific's PC208W software.
4.3.1 PRINTABLE ASCII FORMAT
In the Printable ASCII format, each data point is
preceded by a 2 digit data point ID and a (+) or
(
−
) sign. The ID and fixed spacing of the data
points make particular points easy to find on a
printed output. This format requires 10 bytes
per data point to store on disk.
Figure 4.3-1 shows both high and low resolution
data points in a 12 data point Output Array. The
example data contains Day, Hour-Minute, and
Seconds in the 2nd - 4th data points.
REMEMBER! You must specifically program