Campbell CR800 Specifications download pdf (Page 103)

Section 4. CRBasic - Native Language Programming

is 1 second, three scans are buffered, and the measurements and output

continue indefinitely.

4.4 Variable Data Types

The declaration of variables (via the DIM or the PUBLIC statement) allow an

optional type descriptor AS that specifies the data type. The default data type,

without a descriptor, is IEEE4 floating point (FLOAT). The data types are

FLOAT, LONG, BOOLEAN, and STRING.

4.4.1 FLOAT

“AS FLOAT” specifies the default IEEE4 data type. If no data type is

explicitly specified with the AS statement, then FLOAT is assumed.

Public Z, RefTemp, TCTemp(3)

Public X AS FLOAT

4.4.2 LONG

“AS LONG” specifies the variable as a 32 bit long integer, ranging from –

2,147,483,648 to +2,147,483,647 (31 bits plus the sign bit). There are two

possible reasons a user would do this: (1) speed, since the OS can do math on

integers faster that with floats, and (2) resolution, since the LONG has 31 bits

compared to the 24 bits in the IEEE4.

Examples:

Dim I AS LONG

Public LongCounter AS LONG

4.4.3 BOOLEAN

“AS BOOLEAN” specifies the variable as a 4 byte Boolean. Boolean

variables are typically used for flags and to represent conditions or hardware

that have only 2 states (e.g., On/Off, Ports). A Boolean variable uses the same

32 bit long integer format as a LONG but can set to only one of two values:

True, which is represented as –1, and false, which is represented with 0. The

Boolean data type allows application software to display it as an ON/OFF,

TRUE/FALSE , RED/BLUE, etc.

Public Switches(8) AS Boolean, FLAGS(16) AS Boolean

4.4.4 STRING

“AS STRING * size” specifies the variable as a string of ASCII characters,

NULL terminated, with size specifying the maximum number of characters in

the string. A string is convenient in handling serial sensors, dial strings, text

messages, etc.

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Campbell CR800 Specifications Page 103