Micromod Micro-DCI: 53MC5000 Multi-Loop Process Controller CUSTOMIZATION GUIDE - Manual (Page 104)

3.4 Custom F-CIM Module
A custom F-CIM module is a custom F-TRAN subroutine which follows specific rules. The user can
write either reusable or non-reusable F-CIM modules. If database values are treated as temporarily
stored, the module is reusable . If any database value is retained (must remain unchanged be-
tween successful control scans), the module is non-reusable.
The rules for a F-CIM are as follows:
• The output of the module must be in datapoint C255 when the R (return) command
is encountered.
• The S
n-1
input is contained in C255; and F253, F254 and F255 contain the
database name which is to be used as the A, B and C inputs respectively.
The following example is the F-TRAN program which is F-CIM85.
\F-CIM85\
\REUSABLE\
\INPUTS\
\X\
\A\
\B\
C255 = C255 F * 253 * F * 254 +\S n = AX + B\
R
To have a single F-CIM perform the PID controller operation,replace F-CIM’s 41, 43, 44 and 47
with the following custom F-CIM. This user defined module uses the F-TRAN control subroutines
G0, G4, G8 and G12 together to produce the control operation. The standard F-CIM’s use the sub-
routines individually and require four steps to realize the PID control operation. Generating this cus-
tom F-CIM reduces flexibility, but saves the user three steps in the program.
The following example of a custom F-CIM replaces standard F-CIM’s 41, 43, 44 and 47.
MODULAR CONTROLLER CUSTOMIZATION GUIDE
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