Campbell Scientific CR9000X Measurement and Control System - Manual (Page 134)

Section 4. CRBasic – Native Language Programming
10) Put together what you know, and you have a working program:
‘Define Constants
Const TCMult = 1.8 : Const TCOffset = 32
Const P1Mult = 50 : Const P1Offset = 0
Const P2Mult = 200 : Const P2offset = 0
‘ Define Public Variables
Public RefTemp, TC(3) 'Variable for ref temp & 3 Element array for temperatures
Public Press(2) 'Declare 2 Element array for pressures
‘Declare Units
Units RefTemp = degC : Units TC = degF : Units Press = psi
‘Declare Aliasess
Alias TC(1) = Ambient : Alias TC(2) = InletT : Alias TC(3) = OutletT
Alias Press(1) = InletP : Alias Press(2) = OutletP
‘Define Data Tables Constants
DataTable (Temps,1,-1)
CardOut (0 ,-1)
DataInterval (0,100,mSec,10)
Sample (1,RefTemp,IEEE4)
Sample (3,TC(),IEEE4)
EndTable
DataTable (Pressure,1,-1)
CardOut (0 ,-1)
DataInterval (0,10,mSec,10)
Sample (2,Press(),IEEE4)
EndTable
BeginProg
‘Setup Main Program Scan
Scan (10,mSec,0,0)
ModuleTemp (RefTemp,1,4,0)
TCDiff (TC(),3,mV50C,4,1,TypeK,RefTemp,True ,40,100, TCMult,TCOffset)
BrFull (Press(1),1,mV50,4,4,5,7,1,5000,True ,True ,30,100,P1Mult,P1Offset)
BrFull (Press(2),1,mV50,4,4,5,7,1,5000,True ,True ,30,100,P2Mult,P2Offset)
CallTable Temps
CallTable Pressure
NextScan
EndProg
4.2 CRBasic Programming
4.2.1 Fundamental elements of CRBASIC include:
• Variables – named program elements, with reserved memory locations,
into which are stored values that may vary during program execution.
Values are typically the result of measurements and processing. Variables
are given an alphanumeric name and can be dimensioned into arrays of
related data.
• Constants – named program elements, with reserved memory locations,
into which are stored values that cannot vary during program execution.
Constants are given alphanumeric names and assigned values at the
beginning declaration section of a CRBASIC program.
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