Campbell Scientific CR200X CR200/CR200X-series Dataloggers - Page 87

Dimensions, 6.1.3, Data Types, 6.1.4, Flags

Page 87 highlights

Section 9. Programming CRBASIC EXAMPLE 4. Public TempC(4) Public TempF(4) Dim T Using a variable array in calculations BeginProg Scan (1,Sec,0,0) Therm109 (TempC(),4,1,Ex1,1.0,0) For T = 1 To 4 TempF(T) = TempC(T) * 1.8 + 32 Next NextScan EndProg 9.6.1.2 Dimensions The CR200(X) cannot use multi-dimensioned arrays. 9.6.1.3 Data Types Variables, calculations, and stored data use IEEE4 4-byte floating point, a binary format, with least significant bit first. Time is stored as integer seconds since midnight, the start of 1990, which is also a 4-byte number. Word Size 4 bytes CR200(X) IEEE4 Data Range Resolution ±1.8 x 10-38 to ±1.7 x 1038 24 bits (about 7 digits) 9.6.1.4 Flags Flags are a useful program control tool. While any variable can be used as a flag, variables named "Flag" works best because datalogger support software automatically adds variables call "Flag" to the Ports and Flags window. Because the CR200(X) does not support the Boolean data type, the IIF function may be used to distinguish between zero and non-zero values, effectively creating a Boolean value. The value of -1(all bits on) is defined as true and the value of zero (all bits off) is defined as false. CRBASIC EXAMPLE. Flag Declaration and Use (p. 76) shows an example using a flag to initiate measurements. 75

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Section 9.
Programming
CRBASIC EXAMPLE 4.
Using a variable array in calculations
Public TempC(4)
Public TempF(4)
Dim T
BeginProg
Scan (1,Sec,0,0)
Therm109 (TempC(),4,1,Ex1,1.0,0)
For T = 1 To 4
TempF(T) = TempC(T) * 1.8 + 32
Next
NextScan
EndProg
9.6.1.2
Dimensions
The CR200(X) cannot use multi-dimensioned arrays.
9.6.1.3
Data Types
Variables, calculations, and stored data use IEEE4 4-byte floating point, a
binary format, with least significant bit first.
Time is stored as integer seconds
since midnight, the start of 1990, which is also a 4-byte number.
CR200(X) IEEE4 Data
Word Size
Range
Resolution
4 bytes
±1.8 x 10-38 to
±1.7 x 1038
24 bits (about 7 digits)
9.6.1.4
Flags
Flags are a useful program control tool. While any variable can be used as a
flag,
variables named "Flag" works best because datalogger support software
automatically adds variables call "Flag" to the Ports and Flags window. Because
the CR200(X) does not support the Boolean data type, the IIF function may be
used to distinguish between zero and non-zero values, effectively creating a
Boolean value.
The value
of -1(all bits on) is defined as true and the value of
zero (all bits off) is defined as false.
CRBASIC EXAMPLE. Flag Declaration
and Use
(p. 76) shows an example using a flag to initiate measurements.
75