Campbell CR800 Series, Руководство оператора

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Section 7. Installation
130
Data Types in Final-Storage Memory
Name Argument Description
Word
Size
(Bytes)
Notes Resolution / Range
NSEC
NSEC
Time stamp 8
Divided up as four bytes of
seconds since 1990 and four bytes
of nanoseconds into the second.
Used to record and process time
data. See NSEC Data Type
(p. 198).
1 nanosecond
String String ASCII string
Minimum
: 3 (4
with null
terminato
r)
Default:
24
Maximu
m:
limited
only to
the size of
available
CR800
memory.
See caution.
1
String size is defined by the
CR800 operating system and
CRBasic program.
When converting from
STRING
to FLOAT , numerics at the
beginning of a string convert, but
conversion stops when a non-
numeric is encountered. If the
string begins with a non-numeric,
the FLOAT will be NAN . If the
string contains multiple numeric
values separated by non-numeric
characters, the SplitStr()
instruction can be used to parse
out the numeric values. See the
sections String Operations
(p. 303)
and Serial I/O
(p. 279).
.
Unless declared otherwise, string size
is 24 bytes or characters. String size is
allocated in multiples of four bytes; for
example, String * 25 , String * 26 ,
String * 27 , and String * 28 allocate
28 bytes (27 usable). Minimum string
size is 4 (3 usable). See CRBasic
Editor Help for more information.
Maximum length is limited only by
available CR800 memory. As a
special case, a string can be declared as
String * 1 . This allows the efficient
storage of a single character. The string
will take up 4 bytes in memory and
when stored in a data table, but it will
hold only one character.
Data Type Declarations
'This program example demonstrates various data type declarations.
'Data type declarations associated with any one variable occur twice: first in a Public
'or Dim statement, then in a DataTable/EndTable segment. If not otherwise specified, data
'types default to floating point: As Float in Public or Dim declarations, FP2 in data
'table declarations.
'Float Variable Examples
Public Z
Public X As Float
'Long Variable Example
Public CR800Time As Long
Public PosCounter As Long
Public PosNegCounter As Long